root/jidctint.c
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DEFINITIONS
This source file includes following definitions.
- jpeg_idct_islow
- jpeg_idct_7x7
- jpeg_idct_6x6
- jpeg_idct_5x5
- jpeg_idct_4x4
- jpeg_idct_3x3
- jpeg_idct_2x2
- jpeg_idct_1x1
- jpeg_idct_9x9
- jpeg_idct_10x10
- jpeg_idct_11x11
- jpeg_idct_12x12
- jpeg_idct_13x13
- jpeg_idct_14x14
- jpeg_idct_15x15
- jpeg_idct_16x16
- jpeg_idct_16x8
- jpeg_idct_14x7
- jpeg_idct_12x6
- jpeg_idct_10x5
- jpeg_idct_8x4
- jpeg_idct_6x3
- jpeg_idct_4x2
- jpeg_idct_2x1
- jpeg_idct_8x16
- jpeg_idct_7x14
- jpeg_idct_6x12
- jpeg_idct_5x10
- jpeg_idct_4x8
- jpeg_idct_3x6
- jpeg_idct_2x4
- jpeg_idct_1x2
/*
* jidctint.c
*
* Copyright (C) 1991-1998, Thomas G. Lane.
* Modification developed 2002-2009 by Guido Vollbeding.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This file contains a slow-but-accurate integer implementation of the
* inverse DCT (Discrete Cosine Transform). In the IJG code, this routine
* must also perform dequantization of the input coefficients.
*
* A 2-D IDCT can be done by 1-D IDCT on each column followed by 1-D IDCT
* on each row (or vice versa, but it's more convenient to emit a row at
* a time). Direct algorithms are also available, but they are much more
* complex and seem not to be any faster when reduced to code.
*
* This implementation is based on an algorithm described in
* C. Loeffler, A. Ligtenberg and G. Moschytz, "Practical Fast 1-D DCT
* Algorithms with 11 Multiplications", Proc. Int'l. Conf. on Acoustics,
* Speech, and Signal Processing 1989 (ICASSP '89), pp. 988-991.
* The primary algorithm described there uses 11 multiplies and 29 adds.
* We use their alternate method with 12 multiplies and 32 adds.
* The advantage of this method is that no data path contains more than one
* multiplication; this allows a very simple and accurate implementation in
* scaled fixed-point arithmetic, with a minimal number of shifts.
*
* We also provide IDCT routines with various output sample block sizes for
* direct resolution reduction or enlargement and for direct resolving the
* common 2x1 and 1x2 subsampling cases without additional resampling: NxN
* (N=1...16), 2NxN, and Nx2N (N=1...8) pixels for one 8x8 input DCT block.
*
* For N<8 we simply take the corresponding low-frequency coefficients of
* the 8x8 input DCT block and apply an NxN point IDCT on the sub-block
* to yield the downscaled outputs.
* This can be seen as direct low-pass downsampling from the DCT domain
* point of view rather than the usual spatial domain point of view,
* yielding significant computational savings and results at least
* as good as common bilinear (averaging) spatial downsampling.
*
* For N>8 we apply a partial NxN IDCT on the 8 input coefficients as
* lower frequencies and higher frequencies assumed to be zero.
* It turns out that the computational effort is similar to the 8x8 IDCT
* regarding the output size.
* Furthermore, the scaling and descaling is the same for all IDCT sizes.
*
* CAUTION: We rely on the FIX() macro except for the N=1,2,4,8 cases
* since there would be too many additional constants to pre-calculate.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
#include "jdct.h" /* Private declarations for DCT subsystem */
#ifdef DCT_ISLOW_SUPPORTED
/*
* This module is specialized to the case DCTSIZE = 8.
*/
#if DCTSIZE != 8
Sorry, this code only copes with 8x8 DCT blocks. /* deliberate syntax err */
#endif
/*
* The poop on this scaling stuff is as follows:
*
* Each 1-D IDCT step produces outputs which are a factor of sqrt(N)
* larger than the true IDCT outputs. The final outputs are therefore
* a factor of N larger than desired; since N=8 this can be cured by
* a simple right shift at the end of the algorithm. The advantage of
* this arrangement is that we save two multiplications per 1-D IDCT,
* because the y0 and y4 inputs need not be divided by sqrt(N).
*
* We have to do addition and subtraction of the integer inputs, which
* is no problem, and multiplication by fractional constants, which is
* a problem to do in integer arithmetic. We multiply all the constants
* by CONST_SCALE and convert them to integer constants (thus retaining
* CONST_BITS bits of precision in the constants). After doing a
* multiplication we have to divide the product by CONST_SCALE, with proper
* rounding, to produce the correct output. This division can be done
* cheaply as a right shift of CONST_BITS bits. We postpone shifting
* as long as possible so that partial sums can be added together with
* full fractional precision.
*
* The outputs of the first pass are scaled up by PASS1_BITS bits so that
* they are represented to better-than-integral precision. These outputs
* require BITS_IN_JSAMPLE + PASS1_BITS + 3 bits; this fits in a 16-bit word
* with the recommended scaling. (To scale up 12-bit sample data further, an
* intermediate INT32 array would be needed.)
*
* To avoid overflow of the 32-bit intermediate results in pass 2, we must
* have BITS_IN_JSAMPLE + CONST_BITS + PASS1_BITS <= 26. Error analysis
* shows that the values given below are the most effective.
*/
#if BITS_IN_JSAMPLE == 8
#define CONST_BITS 13
#define PASS1_BITS 2
#else
#define CONST_BITS 13
#define PASS1_BITS 1 /* lose a little precision to avoid overflow */
#endif
/* Some C compilers fail to reduce "FIX(constant)" at compile time, thus
* causing a lot of useless floating-point operations at run time.
* To get around this we use the following pre-calculated constants.
* If you change CONST_BITS you may want to add appropriate values.
* (With a reasonable C compiler, you can just rely on the FIX() macro...)
*/
#if CONST_BITS == 13
#define FIX_0_298631336 ((INT32) 2446) /* FIX(0.298631336) */
#define FIX_0_390180644 ((INT32) 3196) /* FIX(0.390180644) */
#define FIX_0_541196100 ((INT32) 4433) /* FIX(0.541196100) */
#define FIX_0_765366865 ((INT32) 6270) /* FIX(0.765366865) */
#define FIX_0_899976223 ((INT32) 7373) /* FIX(0.899976223) */
#define FIX_1_175875602 ((INT32) 9633) /* FIX(1.175875602) */
#define FIX_1_501321110 ((INT32) 12299) /* FIX(1.501321110) */
#define FIX_1_847759065 ((INT32) 15137) /* FIX(1.847759065) */
#define FIX_1_961570560 ((INT32) 16069) /* FIX(1.961570560) */
#define FIX_2_053119869 ((INT32) 16819) /* FIX(2.053119869) */
#define FIX_2_562915447 ((INT32) 20995) /* FIX(2.562915447) */
#define FIX_3_072711026 ((INT32) 25172) /* FIX(3.072711026) */
#else
#define FIX_0_298631336 FIX(0.298631336)
#define FIX_0_390180644 FIX(0.390180644)
#define FIX_0_541196100 FIX(0.541196100)
#define FIX_0_765366865 FIX(0.765366865)
#define FIX_0_899976223 FIX(0.899976223)
#define FIX_1_175875602 FIX(1.175875602)
#define FIX_1_501321110 FIX(1.501321110)
#define FIX_1_847759065 FIX(1.847759065)
#define FIX_1_961570560 FIX(1.961570560)
#define FIX_2_053119869 FIX(2.053119869)
#define FIX_2_562915447 FIX(2.562915447)
#define FIX_3_072711026 FIX(3.072711026)
#endif
/* Multiply an INT32 variable by an INT32 constant to yield an INT32 result.
* For 8-bit samples with the recommended scaling, all the variable
* and constant values involved are no more than 16 bits wide, so a
* 16x16->32 bit multiply can be used instead of a full 32x32 multiply.
* For 12-bit samples, a full 32-bit multiplication will be needed.
*/
#if BITS_IN_JSAMPLE == 8
#define MULTIPLY(var,const) MULTIPLY16C16(var,const)
#else
#define MULTIPLY(var,const) ((var) * (const))
#endif
/* Dequantize a coefficient by multiplying it by the multiplier-table
* entry; produce an int result. In this module, both inputs and result
* are 16 bits or less, so either int or short multiply will work.
*/
#define DEQUANTIZE(coef,quantval) (((ISLOW_MULT_TYPE) (coef)) * (quantval))
/*
* Perform dequantization and inverse DCT on one block of coefficients.
*/
void
jpeg_idct_islow (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp0, tmp1, tmp2, tmp3;
INT32 tmp10, tmp11, tmp12, tmp13;
INT32 z1, z2, z3;
JCOEFPTR inptr;
ISLOW_MULT_TYPE * quantptr;
int * wsptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
int workspace[DCTSIZE2]; /* buffers data between passes */
SHIFT_TEMPS
/* Pass 1: process columns from input, store into work array. */
/* Note results are scaled up by sqrt(8) compared to a true IDCT; */
/* furthermore, we scale the results by 2**PASS1_BITS. */
inptr = coef_block;
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
wsptr = workspace;
for (ctr = DCTSIZE; ctr > 0; ctr--) {
/* Due to quantization, we will usually find that many of the input
* coefficients are zero, especially the AC terms. We can exploit this
* by short-circuiting the IDCT calculation for any column in which all
* the AC terms are zero. In that case each output is equal to the
* DC coefficient (with scale factor as needed).
* With typical images and quantization tables, half or more of the
* column DCT calculations can be simplified this way.
*/
if (inptr[DCTSIZE*1] == 0 && inptr[DCTSIZE*2] == 0 &&
inptr[DCTSIZE*3] == 0 && inptr[DCTSIZE*4] == 0 &&
inptr[DCTSIZE*5] == 0 && inptr[DCTSIZE*6] == 0 &&
inptr[DCTSIZE*7] == 0) {
/* AC terms all zero */
int dcval = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]) << PASS1_BITS;
wsptr[DCTSIZE*0] = dcval;
wsptr[DCTSIZE*1] = dcval;
wsptr[DCTSIZE*2] = dcval;
wsptr[DCTSIZE*3] = dcval;
wsptr[DCTSIZE*4] = dcval;
wsptr[DCTSIZE*5] = dcval;
wsptr[DCTSIZE*6] = dcval;
wsptr[DCTSIZE*7] = dcval;
inptr++; /* advance pointers to next column */
quantptr++;
wsptr++;
continue;
}
/* Even part: reverse the even part of the forward DCT. */
/* The rotator is sqrt(2)*c(-6). */
z2 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
z3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
z1 = MULTIPLY(z2 + z3, FIX_0_541196100);
tmp2 = z1 + MULTIPLY(z2, FIX_0_765366865);
tmp3 = z1 - MULTIPLY(z3, FIX_1_847759065);
z2 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
z3 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
z2 <<= CONST_BITS;
z3 <<= CONST_BITS;
/* Add fudge factor here for final descale. */
z2 += ONE << (CONST_BITS-PASS1_BITS-1);
tmp0 = z2 + z3;
tmp1 = z2 - z3;
tmp10 = tmp0 + tmp2;
tmp13 = tmp0 - tmp2;
tmp11 = tmp1 + tmp3;
tmp12 = tmp1 - tmp3;
/* Odd part per figure 8; the matrix is unitary and hence its
* transpose is its inverse. i0..i3 are y7,y5,y3,y1 respectively.
*/
tmp0 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
tmp1 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
tmp2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
tmp3 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
z2 = tmp0 + tmp2;
z3 = tmp1 + tmp3;
z1 = MULTIPLY(z2 + z3, FIX_1_175875602); /* sqrt(2) * c3 */
z2 = MULTIPLY(z2, - FIX_1_961570560); /* sqrt(2) * (-c3-c5) */
z3 = MULTIPLY(z3, - FIX_0_390180644); /* sqrt(2) * (c5-c3) */
z2 += z1;
z3 += z1;
z1 = MULTIPLY(tmp0 + tmp3, - FIX_0_899976223); /* sqrt(2) * (c7-c3) */
tmp0 = MULTIPLY(tmp0, FIX_0_298631336); /* sqrt(2) * (-c1+c3+c5-c7) */
tmp3 = MULTIPLY(tmp3, FIX_1_501321110); /* sqrt(2) * ( c1+c3-c5-c7) */
tmp0 += z1 + z2;
tmp3 += z1 + z3;
z1 = MULTIPLY(tmp1 + tmp2, - FIX_2_562915447); /* sqrt(2) * (-c1-c3) */
tmp1 = MULTIPLY(tmp1, FIX_2_053119869); /* sqrt(2) * ( c1+c3-c5+c7) */
tmp2 = MULTIPLY(tmp2, FIX_3_072711026); /* sqrt(2) * ( c1+c3+c5-c7) */
tmp1 += z1 + z3;
tmp2 += z1 + z2;
/* Final output stage: inputs are tmp10..tmp13, tmp0..tmp3 */
wsptr[DCTSIZE*0] = (int) RIGHT_SHIFT(tmp10 + tmp3, CONST_BITS-PASS1_BITS);
wsptr[DCTSIZE*7] = (int) RIGHT_SHIFT(tmp10 - tmp3, CONST_BITS-PASS1_BITS);
wsptr[DCTSIZE*1] = (int) RIGHT_SHIFT(tmp11 + tmp2, CONST_BITS-PASS1_BITS);
wsptr[DCTSIZE*6] = (int) RIGHT_SHIFT(tmp11 - tmp2, CONST_BITS-PASS1_BITS);
wsptr[DCTSIZE*2] = (int) RIGHT_SHIFT(tmp12 + tmp1, CONST_BITS-PASS1_BITS);
wsptr[DCTSIZE*5] = (int) RIGHT_SHIFT(tmp12 - tmp1, CONST_BITS-PASS1_BITS);
wsptr[DCTSIZE*3] = (int) RIGHT_SHIFT(tmp13 + tmp0, CONST_BITS-PASS1_BITS);
wsptr[DCTSIZE*4] = (int) RIGHT_SHIFT(tmp13 - tmp0, CONST_BITS-PASS1_BITS);
inptr++; /* advance pointers to next column */
quantptr++;
wsptr++;
}
/* Pass 2: process rows from work array, store into output array. */
/* Note that we must descale the results by a factor of 8 == 2**3, */
/* and also undo the PASS1_BITS scaling. */
wsptr = workspace;
for (ctr = 0; ctr < DCTSIZE; ctr++) {
outptr = output_buf[ctr] + output_col;
/* Rows of zeroes can be exploited in the same way as we did with columns.
* However, the column calculation has created many nonzero AC terms, so
* the simplification applies less often (typically 5% to 10% of the time).
* On machines with very fast multiplication, it's possible that the
* test takes more time than it's worth. In that case this section
* may be commented out.
*/
#ifndef NO_ZERO_ROW_TEST
if (wsptr[1] == 0 && wsptr[2] == 0 && wsptr[3] == 0 && wsptr[4] == 0 &&
wsptr[5] == 0 && wsptr[6] == 0 && wsptr[7] == 0) {
/* AC terms all zero */
JSAMPLE dcval = range_limit[(int) DESCALE((INT32) wsptr[0], PASS1_BITS+3)
& RANGE_MASK];
outptr[0] = dcval;
outptr[1] = dcval;
outptr[2] = dcval;
outptr[3] = dcval;
outptr[4] = dcval;
outptr[5] = dcval;
outptr[6] = dcval;
outptr[7] = dcval;
wsptr += DCTSIZE; /* advance pointer to next row */
continue;
}
#endif
/* Even part: reverse the even part of the forward DCT. */
/* The rotator is sqrt(2)*c(-6). */
z2 = (INT32) wsptr[2];
z3 = (INT32) wsptr[6];
z1 = MULTIPLY(z2 + z3, FIX_0_541196100);
tmp2 = z1 + MULTIPLY(z2, FIX_0_765366865);
tmp3 = z1 - MULTIPLY(z3, FIX_1_847759065);
/* Add fudge factor here for final descale. */
z2 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
z3 = (INT32) wsptr[4];
tmp0 = (z2 + z3) << CONST_BITS;
tmp1 = (z2 - z3) << CONST_BITS;
tmp10 = tmp0 + tmp2;
tmp13 = tmp0 - tmp2;
tmp11 = tmp1 + tmp3;
tmp12 = tmp1 - tmp3;
/* Odd part per figure 8; the matrix is unitary and hence its
* transpose is its inverse. i0..i3 are y7,y5,y3,y1 respectively.
*/
tmp0 = (INT32) wsptr[7];
tmp1 = (INT32) wsptr[5];
tmp2 = (INT32) wsptr[3];
tmp3 = (INT32) wsptr[1];
z2 = tmp0 + tmp2;
z3 = tmp1 + tmp3;
z1 = MULTIPLY(z2 + z3, FIX_1_175875602); /* sqrt(2) * c3 */
z2 = MULTIPLY(z2, - FIX_1_961570560); /* sqrt(2) * (-c3-c5) */
z3 = MULTIPLY(z3, - FIX_0_390180644); /* sqrt(2) * (c5-c3) */
z2 += z1;
z3 += z1;
z1 = MULTIPLY(tmp0 + tmp3, - FIX_0_899976223); /* sqrt(2) * (c7-c3) */
tmp0 = MULTIPLY(tmp0, FIX_0_298631336); /* sqrt(2) * (-c1+c3+c5-c7) */
tmp3 = MULTIPLY(tmp3, FIX_1_501321110); /* sqrt(2) * ( c1+c3-c5-c7) */
tmp0 += z1 + z2;
tmp3 += z1 + z3;
z1 = MULTIPLY(tmp1 + tmp2, - FIX_2_562915447); /* sqrt(2) * (-c1-c3) */
tmp1 = MULTIPLY(tmp1, FIX_2_053119869); /* sqrt(2) * ( c1+c3-c5+c7) */
tmp2 = MULTIPLY(tmp2, FIX_3_072711026); /* sqrt(2) * ( c1+c3+c5-c7) */
tmp1 += z1 + z3;
tmp2 += z1 + z2;
/* Final output stage: inputs are tmp10..tmp13, tmp0..tmp3 */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp3,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp3,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp11 + tmp2,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp11 - tmp2,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp12 + tmp1,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp12 - tmp1,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp13 + tmp0,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp13 - tmp0,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
wsptr += DCTSIZE; /* advance pointer to next row */
}
}
#ifdef IDCT_SCALING_SUPPORTED
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a 7x7 output block.
*
* Optimized algorithm with 12 multiplications in the 1-D kernel.
* cK represents sqrt(2) * cos(K*pi/14).
*/
void
jpeg_idct_7x7 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp0, tmp1, tmp2, tmp10, tmp11, tmp12, tmp13;
INT32 z1, z2, z3;
JCOEFPTR inptr;
ISLOW_MULT_TYPE * quantptr;
int * wsptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
int workspace[7*7]; /* buffers data between passes */
SHIFT_TEMPS
/* Pass 1: process columns from input, store into work array. */
inptr = coef_block;
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
wsptr = workspace;
for (ctr = 0; ctr < 7; ctr++, inptr++, quantptr++, wsptr++) {
/* Even part */
tmp13 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
tmp13 <<= CONST_BITS;
/* Add fudge factor here for final descale. */
tmp13 += ONE << (CONST_BITS-PASS1_BITS-1);
z1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
z2 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
z3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
tmp10 = MULTIPLY(z2 - z3, FIX(0.881747734)); /* c4 */
tmp12 = MULTIPLY(z1 - z2, FIX(0.314692123)); /* c6 */
tmp11 = tmp10 + tmp12 + tmp13 - MULTIPLY(z2, FIX(1.841218003)); /* c2+c4-c6 */
tmp0 = z1 + z3;
z2 -= tmp0;
tmp0 = MULTIPLY(tmp0, FIX(1.274162392)) + tmp13; /* c2 */
tmp10 += tmp0 - MULTIPLY(z3, FIX(0.077722536)); /* c2-c4-c6 */
tmp12 += tmp0 - MULTIPLY(z1, FIX(2.470602249)); /* c2+c4+c6 */
tmp13 += MULTIPLY(z2, FIX(1.414213562)); /* c0 */
/* Odd part */
z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
tmp1 = MULTIPLY(z1 + z2, FIX(0.935414347)); /* (c3+c1-c5)/2 */
tmp2 = MULTIPLY(z1 - z2, FIX(0.170262339)); /* (c3+c5-c1)/2 */
tmp0 = tmp1 - tmp2;
tmp1 += tmp2;
tmp2 = MULTIPLY(z2 + z3, - FIX(1.378756276)); /* -c1 */
tmp1 += tmp2;
z2 = MULTIPLY(z1 + z3, FIX(0.613604268)); /* c5 */
tmp0 += z2;
tmp2 += z2 + MULTIPLY(z3, FIX(1.870828693)); /* c3+c1-c5 */
/* Final output stage */
wsptr[7*0] = (int) RIGHT_SHIFT(tmp10 + tmp0, CONST_BITS-PASS1_BITS);
wsptr[7*6] = (int) RIGHT_SHIFT(tmp10 - tmp0, CONST_BITS-PASS1_BITS);
wsptr[7*1] = (int) RIGHT_SHIFT(tmp11 + tmp1, CONST_BITS-PASS1_BITS);
wsptr[7*5] = (int) RIGHT_SHIFT(tmp11 - tmp1, CONST_BITS-PASS1_BITS);
wsptr[7*2] = (int) RIGHT_SHIFT(tmp12 + tmp2, CONST_BITS-PASS1_BITS);
wsptr[7*4] = (int) RIGHT_SHIFT(tmp12 - tmp2, CONST_BITS-PASS1_BITS);
wsptr[7*3] = (int) RIGHT_SHIFT(tmp13, CONST_BITS-PASS1_BITS);
}
/* Pass 2: process 7 rows from work array, store into output array. */
wsptr = workspace;
for (ctr = 0; ctr < 7; ctr++) {
outptr = output_buf[ctr] + output_col;
/* Even part */
/* Add fudge factor here for final descale. */
tmp13 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
tmp13 <<= CONST_BITS;
z1 = (INT32) wsptr[2];
z2 = (INT32) wsptr[4];
z3 = (INT32) wsptr[6];
tmp10 = MULTIPLY(z2 - z3, FIX(0.881747734)); /* c4 */
tmp12 = MULTIPLY(z1 - z2, FIX(0.314692123)); /* c6 */
tmp11 = tmp10 + tmp12 + tmp13 - MULTIPLY(z2, FIX(1.841218003)); /* c2+c4-c6 */
tmp0 = z1 + z3;
z2 -= tmp0;
tmp0 = MULTIPLY(tmp0, FIX(1.274162392)) + tmp13; /* c2 */
tmp10 += tmp0 - MULTIPLY(z3, FIX(0.077722536)); /* c2-c4-c6 */
tmp12 += tmp0 - MULTIPLY(z1, FIX(2.470602249)); /* c2+c4+c6 */
tmp13 += MULTIPLY(z2, FIX(1.414213562)); /* c0 */
/* Odd part */
z1 = (INT32) wsptr[1];
z2 = (INT32) wsptr[3];
z3 = (INT32) wsptr[5];
tmp1 = MULTIPLY(z1 + z2, FIX(0.935414347)); /* (c3+c1-c5)/2 */
tmp2 = MULTIPLY(z1 - z2, FIX(0.170262339)); /* (c3+c5-c1)/2 */
tmp0 = tmp1 - tmp2;
tmp1 += tmp2;
tmp2 = MULTIPLY(z2 + z3, - FIX(1.378756276)); /* -c1 */
tmp1 += tmp2;
z2 = MULTIPLY(z1 + z3, FIX(0.613604268)); /* c5 */
tmp0 += z2;
tmp2 += z2 + MULTIPLY(z3, FIX(1.870828693)); /* c3+c1-c5 */
/* Final output stage */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp0,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp0,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp11 + tmp1,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp11 - tmp1,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp12 + tmp2,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp12 - tmp2,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp13,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
wsptr += 7; /* advance pointer to next row */
}
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a reduced-size 6x6 output block.
*
* Optimized algorithm with 3 multiplications in the 1-D kernel.
* cK represents sqrt(2) * cos(K*pi/12).
*/
void
jpeg_idct_6x6 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp0, tmp1, tmp2, tmp10, tmp11, tmp12;
INT32 z1, z2, z3;
JCOEFPTR inptr;
ISLOW_MULT_TYPE * quantptr;
int * wsptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
int workspace[6*6]; /* buffers data between passes */
SHIFT_TEMPS
/* Pass 1: process columns from input, store into work array. */
inptr = coef_block;
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
wsptr = workspace;
for (ctr = 0; ctr < 6; ctr++, inptr++, quantptr++, wsptr++) {
/* Even part */
tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
tmp0 <<= CONST_BITS;
/* Add fudge factor here for final descale. */
tmp0 += ONE << (CONST_BITS-PASS1_BITS-1);
tmp2 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
tmp10 = MULTIPLY(tmp2, FIX(0.707106781)); /* c4 */
tmp1 = tmp0 + tmp10;
tmp11 = RIGHT_SHIFT(tmp0 - tmp10 - tmp10, CONST_BITS-PASS1_BITS);
tmp10 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
tmp0 = MULTIPLY(tmp10, FIX(1.224744871)); /* c2 */
tmp10 = tmp1 + tmp0;
tmp12 = tmp1 - tmp0;
/* Odd part */
z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
tmp1 = MULTIPLY(z1 + z3, FIX(0.366025404)); /* c5 */
tmp0 = tmp1 + ((z1 + z2) << CONST_BITS);
tmp2 = tmp1 + ((z3 - z2) << CONST_BITS);
tmp1 = (z1 - z2 - z3) << PASS1_BITS;
/* Final output stage */
wsptr[6*0] = (int) RIGHT_SHIFT(tmp10 + tmp0, CONST_BITS-PASS1_BITS);
wsptr[6*5] = (int) RIGHT_SHIFT(tmp10 - tmp0, CONST_BITS-PASS1_BITS);
wsptr[6*1] = (int) (tmp11 + tmp1);
wsptr[6*4] = (int) (tmp11 - tmp1);
wsptr[6*2] = (int) RIGHT_SHIFT(tmp12 + tmp2, CONST_BITS-PASS1_BITS);
wsptr[6*3] = (int) RIGHT_SHIFT(tmp12 - tmp2, CONST_BITS-PASS1_BITS);
}
/* Pass 2: process 6 rows from work array, store into output array. */
wsptr = workspace;
for (ctr = 0; ctr < 6; ctr++) {
outptr = output_buf[ctr] + output_col;
/* Even part */
/* Add fudge factor here for final descale. */
tmp0 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
tmp0 <<= CONST_BITS;
tmp2 = (INT32) wsptr[4];
tmp10 = MULTIPLY(tmp2, FIX(0.707106781)); /* c4 */
tmp1 = tmp0 + tmp10;
tmp11 = tmp0 - tmp10 - tmp10;
tmp10 = (INT32) wsptr[2];
tmp0 = MULTIPLY(tmp10, FIX(1.224744871)); /* c2 */
tmp10 = tmp1 + tmp0;
tmp12 = tmp1 - tmp0;
/* Odd part */
z1 = (INT32) wsptr[1];
z2 = (INT32) wsptr[3];
z3 = (INT32) wsptr[5];
tmp1 = MULTIPLY(z1 + z3, FIX(0.366025404)); /* c5 */
tmp0 = tmp1 + ((z1 + z2) << CONST_BITS);
tmp2 = tmp1 + ((z3 - z2) << CONST_BITS);
tmp1 = (z1 - z2 - z3) << CONST_BITS;
/* Final output stage */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp0,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp0,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp11 + tmp1,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp11 - tmp1,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp12 + tmp2,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp12 - tmp2,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
wsptr += 6; /* advance pointer to next row */
}
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a reduced-size 5x5 output block.
*
* Optimized algorithm with 5 multiplications in the 1-D kernel.
* cK represents sqrt(2) * cos(K*pi/10).
*/
void
jpeg_idct_5x5 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp0, tmp1, tmp10, tmp11, tmp12;
INT32 z1, z2, z3;
JCOEFPTR inptr;
ISLOW_MULT_TYPE * quantptr;
int * wsptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
int workspace[5*5]; /* buffers data between passes */
SHIFT_TEMPS
/* Pass 1: process columns from input, store into work array. */
inptr = coef_block;
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
wsptr = workspace;
for (ctr = 0; ctr < 5; ctr++, inptr++, quantptr++, wsptr++) {
/* Even part */
tmp12 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
tmp12 <<= CONST_BITS;
/* Add fudge factor here for final descale. */
tmp12 += ONE << (CONST_BITS-PASS1_BITS-1);
tmp0 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
tmp1 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
z1 = MULTIPLY(tmp0 + tmp1, FIX(0.790569415)); /* (c2+c4)/2 */
z2 = MULTIPLY(tmp0 - tmp1, FIX(0.353553391)); /* (c2-c4)/2 */
z3 = tmp12 + z2;
tmp10 = z3 + z1;
tmp11 = z3 - z1;
tmp12 -= z2 << 2;
/* Odd part */
z2 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
z3 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
z1 = MULTIPLY(z2 + z3, FIX(0.831253876)); /* c3 */
tmp0 = z1 + MULTIPLY(z2, FIX(0.513743148)); /* c1-c3 */
tmp1 = z1 - MULTIPLY(z3, FIX(2.176250899)); /* c1+c3 */
/* Final output stage */
wsptr[5*0] = (int) RIGHT_SHIFT(tmp10 + tmp0, CONST_BITS-PASS1_BITS);
wsptr[5*4] = (int) RIGHT_SHIFT(tmp10 - tmp0, CONST_BITS-PASS1_BITS);
wsptr[5*1] = (int) RIGHT_SHIFT(tmp11 + tmp1, CONST_BITS-PASS1_BITS);
wsptr[5*3] = (int) RIGHT_SHIFT(tmp11 - tmp1, CONST_BITS-PASS1_BITS);
wsptr[5*2] = (int) RIGHT_SHIFT(tmp12, CONST_BITS-PASS1_BITS);
}
/* Pass 2: process 5 rows from work array, store into output array. */
wsptr = workspace;
for (ctr = 0; ctr < 5; ctr++) {
outptr = output_buf[ctr] + output_col;
/* Even part */
/* Add fudge factor here for final descale. */
tmp12 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
tmp12 <<= CONST_BITS;
tmp0 = (INT32) wsptr[2];
tmp1 = (INT32) wsptr[4];
z1 = MULTIPLY(tmp0 + tmp1, FIX(0.790569415)); /* (c2+c4)/2 */
z2 = MULTIPLY(tmp0 - tmp1, FIX(0.353553391)); /* (c2-c4)/2 */
z3 = tmp12 + z2;
tmp10 = z3 + z1;
tmp11 = z3 - z1;
tmp12 -= z2 << 2;
/* Odd part */
z2 = (INT32) wsptr[1];
z3 = (INT32) wsptr[3];
z1 = MULTIPLY(z2 + z3, FIX(0.831253876)); /* c3 */
tmp0 = z1 + MULTIPLY(z2, FIX(0.513743148)); /* c1-c3 */
tmp1 = z1 - MULTIPLY(z3, FIX(2.176250899)); /* c1+c3 */
/* Final output stage */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp0,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp0,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp11 + tmp1,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp11 - tmp1,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp12,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
wsptr += 5; /* advance pointer to next row */
}
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a reduced-size 4x4 output block.
*
* Optimized algorithm with 3 multiplications in the 1-D kernel.
* cK represents sqrt(2) * cos(K*pi/16) [refers to 8-point IDCT].
*/
void
jpeg_idct_4x4 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp0, tmp2, tmp10, tmp12;
INT32 z1, z2, z3;
JCOEFPTR inptr;
ISLOW_MULT_TYPE * quantptr;
int * wsptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
int workspace[4*4]; /* buffers data between passes */
SHIFT_TEMPS
/* Pass 1: process columns from input, store into work array. */
inptr = coef_block;
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
wsptr = workspace;
for (ctr = 0; ctr < 4; ctr++, inptr++, quantptr++, wsptr++) {
/* Even part */
tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
tmp2 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
tmp10 = (tmp0 + tmp2) << PASS1_BITS;
tmp12 = (tmp0 - tmp2) << PASS1_BITS;
/* Odd part */
/* Same rotation as in the even part of the 8x8 LL&M IDCT */
z2 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
z3 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
z1 = MULTIPLY(z2 + z3, FIX_0_541196100); /* c6 */
/* Add fudge factor here for final descale. */
z1 += ONE << (CONST_BITS-PASS1_BITS-1);
tmp0 = RIGHT_SHIFT(z1 + MULTIPLY(z2, FIX_0_765366865), /* c2-c6 */
CONST_BITS-PASS1_BITS);
tmp2 = RIGHT_SHIFT(z1 - MULTIPLY(z3, FIX_1_847759065), /* c2+c6 */
CONST_BITS-PASS1_BITS);
/* Final output stage */
wsptr[4*0] = (int) (tmp10 + tmp0);
wsptr[4*3] = (int) (tmp10 - tmp0);
wsptr[4*1] = (int) (tmp12 + tmp2);
wsptr[4*2] = (int) (tmp12 - tmp2);
}
/* Pass 2: process 4 rows from work array, store into output array. */
wsptr = workspace;
for (ctr = 0; ctr < 4; ctr++) {
outptr = output_buf[ctr] + output_col;
/* Even part */
/* Add fudge factor here for final descale. */
tmp0 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
tmp2 = (INT32) wsptr[2];
tmp10 = (tmp0 + tmp2) << CONST_BITS;
tmp12 = (tmp0 - tmp2) << CONST_BITS;
/* Odd part */
/* Same rotation as in the even part of the 8x8 LL&M IDCT */
z2 = (INT32) wsptr[1];
z3 = (INT32) wsptr[3];
z1 = MULTIPLY(z2 + z3, FIX_0_541196100); /* c6 */
tmp0 = z1 + MULTIPLY(z2, FIX_0_765366865); /* c2-c6 */
tmp2 = z1 - MULTIPLY(z3, FIX_1_847759065); /* c2+c6 */
/* Final output stage */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp0,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp0,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp12 + tmp2,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp12 - tmp2,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
wsptr += 4; /* advance pointer to next row */
}
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a reduced-size 3x3 output block.
*
* Optimized algorithm with 2 multiplications in the 1-D kernel.
* cK represents sqrt(2) * cos(K*pi/6).
*/
void
jpeg_idct_3x3 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp0, tmp2, tmp10, tmp12;
JCOEFPTR inptr;
ISLOW_MULT_TYPE * quantptr;
int * wsptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
int workspace[3*3]; /* buffers data between passes */
SHIFT_TEMPS
/* Pass 1: process columns from input, store into work array. */
inptr = coef_block;
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
wsptr = workspace;
for (ctr = 0; ctr < 3; ctr++, inptr++, quantptr++, wsptr++) {
/* Even part */
tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
tmp0 <<= CONST_BITS;
/* Add fudge factor here for final descale. */
tmp0 += ONE << (CONST_BITS-PASS1_BITS-1);
tmp2 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
tmp12 = MULTIPLY(tmp2, FIX(0.707106781)); /* c2 */
tmp10 = tmp0 + tmp12;
tmp2 = tmp0 - tmp12 - tmp12;
/* Odd part */
tmp12 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
tmp0 = MULTIPLY(tmp12, FIX(1.224744871)); /* c1 */
/* Final output stage */
wsptr[3*0] = (int) RIGHT_SHIFT(tmp10 + tmp0, CONST_BITS-PASS1_BITS);
wsptr[3*2] = (int) RIGHT_SHIFT(tmp10 - tmp0, CONST_BITS-PASS1_BITS);
wsptr[3*1] = (int) RIGHT_SHIFT(tmp2, CONST_BITS-PASS1_BITS);
}
/* Pass 2: process 3 rows from work array, store into output array. */
wsptr = workspace;
for (ctr = 0; ctr < 3; ctr++) {
outptr = output_buf[ctr] + output_col;
/* Even part */
/* Add fudge factor here for final descale. */
tmp0 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
tmp0 <<= CONST_BITS;
tmp2 = (INT32) wsptr[2];
tmp12 = MULTIPLY(tmp2, FIX(0.707106781)); /* c2 */
tmp10 = tmp0 + tmp12;
tmp2 = tmp0 - tmp12 - tmp12;
/* Odd part */
tmp12 = (INT32) wsptr[1];
tmp0 = MULTIPLY(tmp12, FIX(1.224744871)); /* c1 */
/* Final output stage */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp0,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp0,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp2,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
wsptr += 3; /* advance pointer to next row */
}
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a reduced-size 2x2 output block.
*
* Multiplication-less algorithm.
*/
void
jpeg_idct_2x2 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp0, tmp1, tmp2, tmp3, tmp4, tmp5;
ISLOW_MULT_TYPE * quantptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
SHIFT_TEMPS
/* Pass 1: process columns from input. */
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
/* Column 0 */
tmp4 = DEQUANTIZE(coef_block[DCTSIZE*0], quantptr[DCTSIZE*0]);
tmp5 = DEQUANTIZE(coef_block[DCTSIZE*1], quantptr[DCTSIZE*1]);
/* Add fudge factor here for final descale. */
tmp4 += ONE << 2;
tmp0 = tmp4 + tmp5;
tmp2 = tmp4 - tmp5;
/* Column 1 */
tmp4 = DEQUANTIZE(coef_block[DCTSIZE*0+1], quantptr[DCTSIZE*0+1]);
tmp5 = DEQUANTIZE(coef_block[DCTSIZE*1+1], quantptr[DCTSIZE*1+1]);
tmp1 = tmp4 + tmp5;
tmp3 = tmp4 - tmp5;
/* Pass 2: process 2 rows, store into output array. */
/* Row 0 */
outptr = output_buf[0] + output_col;
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp0 + tmp1, 3) & RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp0 - tmp1, 3) & RANGE_MASK];
/* Row 1 */
outptr = output_buf[1] + output_col;
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp2 + tmp3, 3) & RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp2 - tmp3, 3) & RANGE_MASK];
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a reduced-size 1x1 output block.
*
* We hardly need an inverse DCT routine for this: just take the
* average pixel value, which is one-eighth of the DC coefficient.
*/
void
jpeg_idct_1x1 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
int dcval;
ISLOW_MULT_TYPE * quantptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
SHIFT_TEMPS
/* 1x1 is trivial: just take the DC coefficient divided by 8. */
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
dcval = DEQUANTIZE(coef_block[0], quantptr[0]);
dcval = (int) DESCALE((INT32) dcval, 3);
output_buf[0][output_col] = range_limit[dcval & RANGE_MASK];
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a 9x9 output block.
*
* Optimized algorithm with 10 multiplications in the 1-D kernel.
* cK represents sqrt(2) * cos(K*pi/18).
*/
void
jpeg_idct_9x9 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp0, tmp1, tmp2, tmp3, tmp10, tmp11, tmp12, tmp13, tmp14;
INT32 z1, z2, z3, z4;
JCOEFPTR inptr;
ISLOW_MULT_TYPE * quantptr;
int * wsptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
int workspace[8*9]; /* buffers data between passes */
SHIFT_TEMPS
/* Pass 1: process columns from input, store into work array. */
inptr = coef_block;
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
wsptr = workspace;
for (ctr = 0; ctr < 8; ctr++, inptr++, quantptr++, wsptr++) {
/* Even part */
tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
tmp0 <<= CONST_BITS;
/* Add fudge factor here for final descale. */
tmp0 += ONE << (CONST_BITS-PASS1_BITS-1);
z1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
z2 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
z3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
tmp3 = MULTIPLY(z3, FIX(0.707106781)); /* c6 */
tmp1 = tmp0 + tmp3;
tmp2 = tmp0 - tmp3 - tmp3;
tmp0 = MULTIPLY(z1 - z2, FIX(0.707106781)); /* c6 */
tmp11 = tmp2 + tmp0;
tmp14 = tmp2 - tmp0 - tmp0;
tmp0 = MULTIPLY(z1 + z2, FIX(1.328926049)); /* c2 */
tmp2 = MULTIPLY(z1, FIX(1.083350441)); /* c4 */
tmp3 = MULTIPLY(z2, FIX(0.245575608)); /* c8 */
tmp10 = tmp1 + tmp0 - tmp3;
tmp12 = tmp1 - tmp0 + tmp2;
tmp13 = tmp1 - tmp2 + tmp3;
/* Odd part */
z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
z4 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
z2 = MULTIPLY(z2, - FIX(1.224744871)); /* -c3 */
tmp2 = MULTIPLY(z1 + z3, FIX(0.909038955)); /* c5 */
tmp3 = MULTIPLY(z1 + z4, FIX(0.483689525)); /* c7 */
tmp0 = tmp2 + tmp3 - z2;
tmp1 = MULTIPLY(z3 - z4, FIX(1.392728481)); /* c1 */
tmp2 += z2 - tmp1;
tmp3 += z2 + tmp1;
tmp1 = MULTIPLY(z1 - z3 - z4, FIX(1.224744871)); /* c3 */
/* Final output stage */
wsptr[8*0] = (int) RIGHT_SHIFT(tmp10 + tmp0, CONST_BITS-PASS1_BITS);
wsptr[8*8] = (int) RIGHT_SHIFT(tmp10 - tmp0, CONST_BITS-PASS1_BITS);
wsptr[8*1] = (int) RIGHT_SHIFT(tmp11 + tmp1, CONST_BITS-PASS1_BITS);
wsptr[8*7] = (int) RIGHT_SHIFT(tmp11 - tmp1, CONST_BITS-PASS1_BITS);
wsptr[8*2] = (int) RIGHT_SHIFT(tmp12 + tmp2, CONST_BITS-PASS1_BITS);
wsptr[8*6] = (int) RIGHT_SHIFT(tmp12 - tmp2, CONST_BITS-PASS1_BITS);
wsptr[8*3] = (int) RIGHT_SHIFT(tmp13 + tmp3, CONST_BITS-PASS1_BITS);
wsptr[8*5] = (int) RIGHT_SHIFT(tmp13 - tmp3, CONST_BITS-PASS1_BITS);
wsptr[8*4] = (int) RIGHT_SHIFT(tmp14, CONST_BITS-PASS1_BITS);
}
/* Pass 2: process 9 rows from work array, store into output array. */
wsptr = workspace;
for (ctr = 0; ctr < 9; ctr++) {
outptr = output_buf[ctr] + output_col;
/* Even part */
/* Add fudge factor here for final descale. */
tmp0 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
tmp0 <<= CONST_BITS;
z1 = (INT32) wsptr[2];
z2 = (INT32) wsptr[4];
z3 = (INT32) wsptr[6];
tmp3 = MULTIPLY(z3, FIX(0.707106781)); /* c6 */
tmp1 = tmp0 + tmp3;
tmp2 = tmp0 - tmp3 - tmp3;
tmp0 = MULTIPLY(z1 - z2, FIX(0.707106781)); /* c6 */
tmp11 = tmp2 + tmp0;
tmp14 = tmp2 - tmp0 - tmp0;
tmp0 = MULTIPLY(z1 + z2, FIX(1.328926049)); /* c2 */
tmp2 = MULTIPLY(z1, FIX(1.083350441)); /* c4 */
tmp3 = MULTIPLY(z2, FIX(0.245575608)); /* c8 */
tmp10 = tmp1 + tmp0 - tmp3;
tmp12 = tmp1 - tmp0 + tmp2;
tmp13 = tmp1 - tmp2 + tmp3;
/* Odd part */
z1 = (INT32) wsptr[1];
z2 = (INT32) wsptr[3];
z3 = (INT32) wsptr[5];
z4 = (INT32) wsptr[7];
z2 = MULTIPLY(z2, - FIX(1.224744871)); /* -c3 */
tmp2 = MULTIPLY(z1 + z3, FIX(0.909038955)); /* c5 */
tmp3 = MULTIPLY(z1 + z4, FIX(0.483689525)); /* c7 */
tmp0 = tmp2 + tmp3 - z2;
tmp1 = MULTIPLY(z3 - z4, FIX(1.392728481)); /* c1 */
tmp2 += z2 - tmp1;
tmp3 += z2 + tmp1;
tmp1 = MULTIPLY(z1 - z3 - z4, FIX(1.224744871)); /* c3 */
/* Final output stage */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp0,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[8] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp0,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp11 + tmp1,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp11 - tmp1,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp12 + tmp2,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp12 - tmp2,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp13 + tmp3,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp13 - tmp3,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp14,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
wsptr += 8; /* advance pointer to next row */
}
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a 10x10 output block.
*
* Optimized algorithm with 12 multiplications in the 1-D kernel.
* cK represents sqrt(2) * cos(K*pi/20).
*/
void
jpeg_idct_10x10 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp10, tmp11, tmp12, tmp13, tmp14;
INT32 tmp20, tmp21, tmp22, tmp23, tmp24;
INT32 z1, z2, z3, z4, z5;
JCOEFPTR inptr;
ISLOW_MULT_TYPE * quantptr;
int * wsptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
int workspace[8*10]; /* buffers data between passes */
SHIFT_TEMPS
/* Pass 1: process columns from input, store into work array. */
inptr = coef_block;
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
wsptr = workspace;
for (ctr = 0; ctr < 8; ctr++, inptr++, quantptr++, wsptr++) {
/* Even part */
z3 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
z3 <<= CONST_BITS;
/* Add fudge factor here for final descale. */
z3 += ONE << (CONST_BITS-PASS1_BITS-1);
z4 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
z1 = MULTIPLY(z4, FIX(1.144122806)); /* c4 */
z2 = MULTIPLY(z4, FIX(0.437016024)); /* c8 */
tmp10 = z3 + z1;
tmp11 = z3 - z2;
tmp22 = RIGHT_SHIFT(z3 - ((z1 - z2) << 1), /* c0 = (c4-c8)*2 */
CONST_BITS-PASS1_BITS);
z2 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
z3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
z1 = MULTIPLY(z2 + z3, FIX(0.831253876)); /* c6 */
tmp12 = z1 + MULTIPLY(z2, FIX(0.513743148)); /* c2-c6 */
tmp13 = z1 - MULTIPLY(z3, FIX(2.176250899)); /* c2+c6 */
tmp20 = tmp10 + tmp12;
tmp24 = tmp10 - tmp12;
tmp21 = tmp11 + tmp13;
tmp23 = tmp11 - tmp13;
/* Odd part */
z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
z4 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
tmp11 = z2 + z4;
tmp13 = z2 - z4;
tmp12 = MULTIPLY(tmp13, FIX(0.309016994)); /* (c3-c7)/2 */
z5 = z3 << CONST_BITS;
z2 = MULTIPLY(tmp11, FIX(0.951056516)); /* (c3+c7)/2 */
z4 = z5 + tmp12;
tmp10 = MULTIPLY(z1, FIX(1.396802247)) + z2 + z4; /* c1 */
tmp14 = MULTIPLY(z1, FIX(0.221231742)) - z2 + z4; /* c9 */
z2 = MULTIPLY(tmp11, FIX(0.587785252)); /* (c1-c9)/2 */
z4 = z5 - tmp12 - (tmp13 << (CONST_BITS - 1));
tmp12 = (z1 - tmp13 - z3) << PASS1_BITS;
tmp11 = MULTIPLY(z1, FIX(1.260073511)) - z2 - z4; /* c3 */
tmp13 = MULTIPLY(z1, FIX(0.642039522)) - z2 + z4; /* c7 */
/* Final output stage */
wsptr[8*0] = (int) RIGHT_SHIFT(tmp20 + tmp10, CONST_BITS-PASS1_BITS);
wsptr[8*9] = (int) RIGHT_SHIFT(tmp20 - tmp10, CONST_BITS-PASS1_BITS);
wsptr[8*1] = (int) RIGHT_SHIFT(tmp21 + tmp11, CONST_BITS-PASS1_BITS);
wsptr[8*8] = (int) RIGHT_SHIFT(tmp21 - tmp11, CONST_BITS-PASS1_BITS);
wsptr[8*2] = (int) (tmp22 + tmp12);
wsptr[8*7] = (int) (tmp22 - tmp12);
wsptr[8*3] = (int) RIGHT_SHIFT(tmp23 + tmp13, CONST_BITS-PASS1_BITS);
wsptr[8*6] = (int) RIGHT_SHIFT(tmp23 - tmp13, CONST_BITS-PASS1_BITS);
wsptr[8*4] = (int) RIGHT_SHIFT(tmp24 + tmp14, CONST_BITS-PASS1_BITS);
wsptr[8*5] = (int) RIGHT_SHIFT(tmp24 - tmp14, CONST_BITS-PASS1_BITS);
}
/* Pass 2: process 10 rows from work array, store into output array. */
wsptr = workspace;
for (ctr = 0; ctr < 10; ctr++) {
outptr = output_buf[ctr] + output_col;
/* Even part */
/* Add fudge factor here for final descale. */
z3 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
z3 <<= CONST_BITS;
z4 = (INT32) wsptr[4];
z1 = MULTIPLY(z4, FIX(1.144122806)); /* c4 */
z2 = MULTIPLY(z4, FIX(0.437016024)); /* c8 */
tmp10 = z3 + z1;
tmp11 = z3 - z2;
tmp22 = z3 - ((z1 - z2) << 1); /* c0 = (c4-c8)*2 */
z2 = (INT32) wsptr[2];
z3 = (INT32) wsptr[6];
z1 = MULTIPLY(z2 + z3, FIX(0.831253876)); /* c6 */
tmp12 = z1 + MULTIPLY(z2, FIX(0.513743148)); /* c2-c6 */
tmp13 = z1 - MULTIPLY(z3, FIX(2.176250899)); /* c2+c6 */
tmp20 = tmp10 + tmp12;
tmp24 = tmp10 - tmp12;
tmp21 = tmp11 + tmp13;
tmp23 = tmp11 - tmp13;
/* Odd part */
z1 = (INT32) wsptr[1];
z2 = (INT32) wsptr[3];
z3 = (INT32) wsptr[5];
z3 <<= CONST_BITS;
z4 = (INT32) wsptr[7];
tmp11 = z2 + z4;
tmp13 = z2 - z4;
tmp12 = MULTIPLY(tmp13, FIX(0.309016994)); /* (c3-c7)/2 */
z2 = MULTIPLY(tmp11, FIX(0.951056516)); /* (c3+c7)/2 */
z4 = z3 + tmp12;
tmp10 = MULTIPLY(z1, FIX(1.396802247)) + z2 + z4; /* c1 */
tmp14 = MULTIPLY(z1, FIX(0.221231742)) - z2 + z4; /* c9 */
z2 = MULTIPLY(tmp11, FIX(0.587785252)); /* (c1-c9)/2 */
z4 = z3 - tmp12 - (tmp13 << (CONST_BITS - 1));
tmp12 = ((z1 - tmp13) << CONST_BITS) - z3;
tmp11 = MULTIPLY(z1, FIX(1.260073511)) - z2 - z4; /* c3 */
tmp13 = MULTIPLY(z1, FIX(0.642039522)) - z2 + z4; /* c7 */
/* Final output stage */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp20 + tmp10,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[9] = range_limit[(int) RIGHT_SHIFT(tmp20 - tmp10,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp21 + tmp11,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[8] = range_limit[(int) RIGHT_SHIFT(tmp21 - tmp11,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp22 + tmp12,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp22 - tmp12,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp23 + tmp13,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp23 - tmp13,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp24 + tmp14,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp24 - tmp14,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
wsptr += 8; /* advance pointer to next row */
}
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a 11x11 output block.
*
* Optimized algorithm with 24 multiplications in the 1-D kernel.
* cK represents sqrt(2) * cos(K*pi/22).
*/
void
jpeg_idct_11x11 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp10, tmp11, tmp12, tmp13, tmp14;
INT32 tmp20, tmp21, tmp22, tmp23, tmp24, tmp25;
INT32 z1, z2, z3, z4;
JCOEFPTR inptr;
ISLOW_MULT_TYPE * quantptr;
int * wsptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
int workspace[8*11]; /* buffers data between passes */
SHIFT_TEMPS
/* Pass 1: process columns from input, store into work array. */
inptr = coef_block;
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
wsptr = workspace;
for (ctr = 0; ctr < 8; ctr++, inptr++, quantptr++, wsptr++) {
/* Even part */
tmp10 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
tmp10 <<= CONST_BITS;
/* Add fudge factor here for final descale. */
tmp10 += ONE << (CONST_BITS-PASS1_BITS-1);
z1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
z2 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
z3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
tmp20 = MULTIPLY(z2 - z3, FIX(2.546640132)); /* c2+c4 */
tmp23 = MULTIPLY(z2 - z1, FIX(0.430815045)); /* c2-c6 */
z4 = z1 + z3;
tmp24 = MULTIPLY(z4, - FIX(1.155664402)); /* -(c2-c10) */
z4 -= z2;
tmp25 = tmp10 + MULTIPLY(z4, FIX(1.356927976)); /* c2 */
tmp21 = tmp20 + tmp23 + tmp25 -
MULTIPLY(z2, FIX(1.821790775)); /* c2+c4+c10-c6 */
tmp20 += tmp25 + MULTIPLY(z3, FIX(2.115825087)); /* c4+c6 */
tmp23 += tmp25 - MULTIPLY(z1, FIX(1.513598477)); /* c6+c8 */
tmp24 += tmp25;
tmp22 = tmp24 - MULTIPLY(z3, FIX(0.788749120)); /* c8+c10 */
tmp24 += MULTIPLY(z2, FIX(1.944413522)) - /* c2+c8 */
MULTIPLY(z1, FIX(1.390975730)); /* c4+c10 */
tmp25 = tmp10 - MULTIPLY(z4, FIX(1.414213562)); /* c0 */
/* Odd part */
z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
z4 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
tmp11 = z1 + z2;
tmp14 = MULTIPLY(tmp11 + z3 + z4, FIX(0.398430003)); /* c9 */
tmp11 = MULTIPLY(tmp11, FIX(0.887983902)); /* c3-c9 */
tmp12 = MULTIPLY(z1 + z3, FIX(0.670361295)); /* c5-c9 */
tmp13 = tmp14 + MULTIPLY(z1 + z4, FIX(0.366151574)); /* c7-c9 */
tmp10 = tmp11 + tmp12 + tmp13 -
MULTIPLY(z1, FIX(0.923107866)); /* c7+c5+c3-c1-2*c9 */
z1 = tmp14 - MULTIPLY(z2 + z3, FIX(1.163011579)); /* c7+c9 */
tmp11 += z1 + MULTIPLY(z2, FIX(2.073276588)); /* c1+c7+3*c9-c3 */
tmp12 += z1 - MULTIPLY(z3, FIX(1.192193623)); /* c3+c5-c7-c9 */
z1 = MULTIPLY(z2 + z4, - FIX(1.798248910)); /* -(c1+c9) */
tmp11 += z1;
tmp13 += z1 + MULTIPLY(z4, FIX(2.102458632)); /* c1+c5+c9-c7 */
tmp14 += MULTIPLY(z2, - FIX(1.467221301)) + /* -(c5+c9) */
MULTIPLY(z3, FIX(1.001388905)) - /* c1-c9 */
MULTIPLY(z4, FIX(1.684843907)); /* c3+c9 */
/* Final output stage */
wsptr[8*0] = (int) RIGHT_SHIFT(tmp20 + tmp10, CONST_BITS-PASS1_BITS);
wsptr[8*10] = (int) RIGHT_SHIFT(tmp20 - tmp10, CONST_BITS-PASS1_BITS);
wsptr[8*1] = (int) RIGHT_SHIFT(tmp21 + tmp11, CONST_BITS-PASS1_BITS);
wsptr[8*9] = (int) RIGHT_SHIFT(tmp21 - tmp11, CONST_BITS-PASS1_BITS);
wsptr[8*2] = (int) RIGHT_SHIFT(tmp22 + tmp12, CONST_BITS-PASS1_BITS);
wsptr[8*8] = (int) RIGHT_SHIFT(tmp22 - tmp12, CONST_BITS-PASS1_BITS);
wsptr[8*3] = (int) RIGHT_SHIFT(tmp23 + tmp13, CONST_BITS-PASS1_BITS);
wsptr[8*7] = (int) RIGHT_SHIFT(tmp23 - tmp13, CONST_BITS-PASS1_BITS);
wsptr[8*4] = (int) RIGHT_SHIFT(tmp24 + tmp14, CONST_BITS-PASS1_BITS);
wsptr[8*6] = (int) RIGHT_SHIFT(tmp24 - tmp14, CONST_BITS-PASS1_BITS);
wsptr[8*5] = (int) RIGHT_SHIFT(tmp25, CONST_BITS-PASS1_BITS);
}
/* Pass 2: process 11 rows from work array, store into output array. */
wsptr = workspace;
for (ctr = 0; ctr < 11; ctr++) {
outptr = output_buf[ctr] + output_col;
/* Even part */
/* Add fudge factor here for final descale. */
tmp10 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
tmp10 <<= CONST_BITS;
z1 = (INT32) wsptr[2];
z2 = (INT32) wsptr[4];
z3 = (INT32) wsptr[6];
tmp20 = MULTIPLY(z2 - z3, FIX(2.546640132)); /* c2+c4 */
tmp23 = MULTIPLY(z2 - z1, FIX(0.430815045)); /* c2-c6 */
z4 = z1 + z3;
tmp24 = MULTIPLY(z4, - FIX(1.155664402)); /* -(c2-c10) */
z4 -= z2;
tmp25 = tmp10 + MULTIPLY(z4, FIX(1.356927976)); /* c2 */
tmp21 = tmp20 + tmp23 + tmp25 -
MULTIPLY(z2, FIX(1.821790775)); /* c2+c4+c10-c6 */
tmp20 += tmp25 + MULTIPLY(z3, FIX(2.115825087)); /* c4+c6 */
tmp23 += tmp25 - MULTIPLY(z1, FIX(1.513598477)); /* c6+c8 */
tmp24 += tmp25;
tmp22 = tmp24 - MULTIPLY(z3, FIX(0.788749120)); /* c8+c10 */
tmp24 += MULTIPLY(z2, FIX(1.944413522)) - /* c2+c8 */
MULTIPLY(z1, FIX(1.390975730)); /* c4+c10 */
tmp25 = tmp10 - MULTIPLY(z4, FIX(1.414213562)); /* c0 */
/* Odd part */
z1 = (INT32) wsptr[1];
z2 = (INT32) wsptr[3];
z3 = (INT32) wsptr[5];
z4 = (INT32) wsptr[7];
tmp11 = z1 + z2;
tmp14 = MULTIPLY(tmp11 + z3 + z4, FIX(0.398430003)); /* c9 */
tmp11 = MULTIPLY(tmp11, FIX(0.887983902)); /* c3-c9 */
tmp12 = MULTIPLY(z1 + z3, FIX(0.670361295)); /* c5-c9 */
tmp13 = tmp14 + MULTIPLY(z1 + z4, FIX(0.366151574)); /* c7-c9 */
tmp10 = tmp11 + tmp12 + tmp13 -
MULTIPLY(z1, FIX(0.923107866)); /* c7+c5+c3-c1-2*c9 */
z1 = tmp14 - MULTIPLY(z2 + z3, FIX(1.163011579)); /* c7+c9 */
tmp11 += z1 + MULTIPLY(z2, FIX(2.073276588)); /* c1+c7+3*c9-c3 */
tmp12 += z1 - MULTIPLY(z3, FIX(1.192193623)); /* c3+c5-c7-c9 */
z1 = MULTIPLY(z2 + z4, - FIX(1.798248910)); /* -(c1+c9) */
tmp11 += z1;
tmp13 += z1 + MULTIPLY(z4, FIX(2.102458632)); /* c1+c5+c9-c7 */
tmp14 += MULTIPLY(z2, - FIX(1.467221301)) + /* -(c5+c9) */
MULTIPLY(z3, FIX(1.001388905)) - /* c1-c9 */
MULTIPLY(z4, FIX(1.684843907)); /* c3+c9 */
/* Final output stage */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp20 + tmp10,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[10] = range_limit[(int) RIGHT_SHIFT(tmp20 - tmp10,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp21 + tmp11,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[9] = range_limit[(int) RIGHT_SHIFT(tmp21 - tmp11,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp22 + tmp12,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[8] = range_limit[(int) RIGHT_SHIFT(tmp22 - tmp12,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp23 + tmp13,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp23 - tmp13,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp24 + tmp14,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp24 - tmp14,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp25,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
wsptr += 8; /* advance pointer to next row */
}
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a 12x12 output block.
*
* Optimized algorithm with 15 multiplications in the 1-D kernel.
* cK represents sqrt(2) * cos(K*pi/24).
*/
void
jpeg_idct_12x12 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp10, tmp11, tmp12, tmp13, tmp14, tmp15;
INT32 tmp20, tmp21, tmp22, tmp23, tmp24, tmp25;
INT32 z1, z2, z3, z4;
JCOEFPTR inptr;
ISLOW_MULT_TYPE * quantptr;
int * wsptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
int workspace[8*12]; /* buffers data between passes */
SHIFT_TEMPS
/* Pass 1: process columns from input, store into work array. */
inptr = coef_block;
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
wsptr = workspace;
for (ctr = 0; ctr < 8; ctr++, inptr++, quantptr++, wsptr++) {
/* Even part */
z3 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
z3 <<= CONST_BITS;
/* Add fudge factor here for final descale. */
z3 += ONE << (CONST_BITS-PASS1_BITS-1);
z4 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
z4 = MULTIPLY(z4, FIX(1.224744871)); /* c4 */
tmp10 = z3 + z4;
tmp11 = z3 - z4;
z1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
z4 = MULTIPLY(z1, FIX(1.366025404)); /* c2 */
z1 <<= CONST_BITS;
z2 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
z2 <<= CONST_BITS;
tmp12 = z1 - z2;
tmp21 = z3 + tmp12;
tmp24 = z3 - tmp12;
tmp12 = z4 + z2;
tmp20 = tmp10 + tmp12;
tmp25 = tmp10 - tmp12;
tmp12 = z4 - z1 - z2;
tmp22 = tmp11 + tmp12;
tmp23 = tmp11 - tmp12;
/* Odd part */
z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
z4 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
tmp11 = MULTIPLY(z2, FIX(1.306562965)); /* c3 */
tmp14 = MULTIPLY(z2, - FIX_0_541196100); /* -c9 */
tmp10 = z1 + z3;
tmp15 = MULTIPLY(tmp10 + z4, FIX(0.860918669)); /* c7 */
tmp12 = tmp15 + MULTIPLY(tmp10, FIX(0.261052384)); /* c5-c7 */
tmp10 = tmp12 + tmp11 + MULTIPLY(z1, FIX(0.280143716)); /* c1-c5 */
tmp13 = MULTIPLY(z3 + z4, - FIX(1.045510580)); /* -(c7+c11) */
tmp12 += tmp13 + tmp14 - MULTIPLY(z3, FIX(1.478575242)); /* c1+c5-c7-c11 */
tmp13 += tmp15 - tmp11 + MULTIPLY(z4, FIX(1.586706681)); /* c1+c11 */
tmp15 += tmp14 - MULTIPLY(z1, FIX(0.676326758)) - /* c7-c11 */
MULTIPLY(z4, FIX(1.982889723)); /* c5+c7 */
z1 -= z4;
z2 -= z3;
z3 = MULTIPLY(z1 + z2, FIX_0_541196100); /* c9 */
tmp11 = z3 + MULTIPLY(z1, FIX_0_765366865); /* c3-c9 */
tmp14 = z3 - MULTIPLY(z2, FIX_1_847759065); /* c3+c9 */
/* Final output stage */
wsptr[8*0] = (int) RIGHT_SHIFT(tmp20 + tmp10, CONST_BITS-PASS1_BITS);
wsptr[8*11] = (int) RIGHT_SHIFT(tmp20 - tmp10, CONST_BITS-PASS1_BITS);
wsptr[8*1] = (int) RIGHT_SHIFT(tmp21 + tmp11, CONST_BITS-PASS1_BITS);
wsptr[8*10] = (int) RIGHT_SHIFT(tmp21 - tmp11, CONST_BITS-PASS1_BITS);
wsptr[8*2] = (int) RIGHT_SHIFT(tmp22 + tmp12, CONST_BITS-PASS1_BITS);
wsptr[8*9] = (int) RIGHT_SHIFT(tmp22 - tmp12, CONST_BITS-PASS1_BITS);
wsptr[8*3] = (int) RIGHT_SHIFT(tmp23 + tmp13, CONST_BITS-PASS1_BITS);
wsptr[8*8] = (int) RIGHT_SHIFT(tmp23 - tmp13, CONST_BITS-PASS1_BITS);
wsptr[8*4] = (int) RIGHT_SHIFT(tmp24 + tmp14, CONST_BITS-PASS1_BITS);
wsptr[8*7] = (int) RIGHT_SHIFT(tmp24 - tmp14, CONST_BITS-PASS1_BITS);
wsptr[8*5] = (int) RIGHT_SHIFT(tmp25 + tmp15, CONST_BITS-PASS1_BITS);
wsptr[8*6] = (int) RIGHT_SHIFT(tmp25 - tmp15, CONST_BITS-PASS1_BITS);
}
/* Pass 2: process 12 rows from work array, store into output array. */
wsptr = workspace;
for (ctr = 0; ctr < 12; ctr++) {
outptr = output_buf[ctr] + output_col;
/* Even part */
/* Add fudge factor here for final descale. */
z3 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
z3 <<= CONST_BITS;
z4 = (INT32) wsptr[4];
z4 = MULTIPLY(z4, FIX(1.224744871)); /* c4 */
tmp10 = z3 + z4;
tmp11 = z3 - z4;
z1 = (INT32) wsptr[2];
z4 = MULTIPLY(z1, FIX(1.366025404)); /* c2 */
z1 <<= CONST_BITS;
z2 = (INT32) wsptr[6];
z2 <<= CONST_BITS;
tmp12 = z1 - z2;
tmp21 = z3 + tmp12;
tmp24 = z3 - tmp12;
tmp12 = z4 + z2;
tmp20 = tmp10 + tmp12;
tmp25 = tmp10 - tmp12;
tmp12 = z4 - z1 - z2;
tmp22 = tmp11 + tmp12;
tmp23 = tmp11 - tmp12;
/* Odd part */
z1 = (INT32) wsptr[1];
z2 = (INT32) wsptr[3];
z3 = (INT32) wsptr[5];
z4 = (INT32) wsptr[7];
tmp11 = MULTIPLY(z2, FIX(1.306562965)); /* c3 */
tmp14 = MULTIPLY(z2, - FIX_0_541196100); /* -c9 */
tmp10 = z1 + z3;
tmp15 = MULTIPLY(tmp10 + z4, FIX(0.860918669)); /* c7 */
tmp12 = tmp15 + MULTIPLY(tmp10, FIX(0.261052384)); /* c5-c7 */
tmp10 = tmp12 + tmp11 + MULTIPLY(z1, FIX(0.280143716)); /* c1-c5 */
tmp13 = MULTIPLY(z3 + z4, - FIX(1.045510580)); /* -(c7+c11) */
tmp12 += tmp13 + tmp14 - MULTIPLY(z3, FIX(1.478575242)); /* c1+c5-c7-c11 */
tmp13 += tmp15 - tmp11 + MULTIPLY(z4, FIX(1.586706681)); /* c1+c11 */
tmp15 += tmp14 - MULTIPLY(z1, FIX(0.676326758)) - /* c7-c11 */
MULTIPLY(z4, FIX(1.982889723)); /* c5+c7 */
z1 -= z4;
z2 -= z3;
z3 = MULTIPLY(z1 + z2, FIX_0_541196100); /* c9 */
tmp11 = z3 + MULTIPLY(z1, FIX_0_765366865); /* c3-c9 */
tmp14 = z3 - MULTIPLY(z2, FIX_1_847759065); /* c3+c9 */
/* Final output stage */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp20 + tmp10,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[11] = range_limit[(int) RIGHT_SHIFT(tmp20 - tmp10,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp21 + tmp11,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[10] = range_limit[(int) RIGHT_SHIFT(tmp21 - tmp11,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp22 + tmp12,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[9] = range_limit[(int) RIGHT_SHIFT(tmp22 - tmp12,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp23 + tmp13,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[8] = range_limit[(int) RIGHT_SHIFT(tmp23 - tmp13,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp24 + tmp14,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp24 - tmp14,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp25 + tmp15,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp25 - tmp15,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
wsptr += 8; /* advance pointer to next row */
}
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a 13x13 output block.
*
* Optimized algorithm with 29 multiplications in the 1-D kernel.
* cK represents sqrt(2) * cos(K*pi/26).
*/
void
jpeg_idct_13x13 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp10, tmp11, tmp12, tmp13, tmp14, tmp15;
INT32 tmp20, tmp21, tmp22, tmp23, tmp24, tmp25, tmp26;
INT32 z1, z2, z3, z4;
JCOEFPTR inptr;
ISLOW_MULT_TYPE * quantptr;
int * wsptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
int workspace[8*13]; /* buffers data between passes */
SHIFT_TEMPS
/* Pass 1: process columns from input, store into work array. */
inptr = coef_block;
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
wsptr = workspace;
for (ctr = 0; ctr < 8; ctr++, inptr++, quantptr++, wsptr++) {
/* Even part */
z1 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
z1 <<= CONST_BITS;
/* Add fudge factor here for final descale. */
z1 += ONE << (CONST_BITS-PASS1_BITS-1);
z2 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
z3 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
z4 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
tmp10 = z3 + z4;
tmp11 = z3 - z4;
tmp12 = MULTIPLY(tmp10, FIX(1.155388986)); /* (c4+c6)/2 */
tmp13 = MULTIPLY(tmp11, FIX(0.096834934)) + z1; /* (c4-c6)/2 */
tmp20 = MULTIPLY(z2, FIX(1.373119086)) + tmp12 + tmp13; /* c2 */
tmp22 = MULTIPLY(z2, FIX(0.501487041)) - tmp12 + tmp13; /* c10 */
tmp12 = MULTIPLY(tmp10, FIX(0.316450131)); /* (c8-c12)/2 */
tmp13 = MULTIPLY(tmp11, FIX(0.486914739)) + z1; /* (c8+c12)/2 */
tmp21 = MULTIPLY(z2, FIX(1.058554052)) - tmp12 + tmp13; /* c6 */
tmp25 = MULTIPLY(z2, - FIX(1.252223920)) + tmp12 + tmp13; /* c4 */
tmp12 = MULTIPLY(tmp10, FIX(0.435816023)); /* (c2-c10)/2 */
tmp13 = MULTIPLY(tmp11, FIX(0.937303064)) - z1; /* (c2+c10)/2 */
tmp23 = MULTIPLY(z2, - FIX(0.170464608)) - tmp12 - tmp13; /* c12 */
tmp24 = MULTIPLY(z2, - FIX(0.803364869)) + tmp12 - tmp13; /* c8 */
tmp26 = MULTIPLY(tmp11 - z2, FIX(1.414213562)) + z1; /* c0 */
/* Odd part */
z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
z4 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
tmp11 = MULTIPLY(z1 + z2, FIX(1.322312651)); /* c3 */
tmp12 = MULTIPLY(z1 + z3, FIX(1.163874945)); /* c5 */
tmp15 = z1 + z4;
tmp13 = MULTIPLY(tmp15, FIX(0.937797057)); /* c7 */
tmp10 = tmp11 + tmp12 + tmp13 -
MULTIPLY(z1, FIX(2.020082300)); /* c7+c5+c3-c1 */
tmp14 = MULTIPLY(z2 + z3, - FIX(0.338443458)); /* -c11 */
tmp11 += tmp14 + MULTIPLY(z2, FIX(0.837223564)); /* c5+c9+c11-c3 */
tmp12 += tmp14 - MULTIPLY(z3, FIX(1.572116027)); /* c1+c5-c9-c11 */
tmp14 = MULTIPLY(z2 + z4, - FIX(1.163874945)); /* -c5 */
tmp11 += tmp14;
tmp13 += tmp14 + MULTIPLY(z4, FIX(2.205608352)); /* c3+c5+c9-c7 */
tmp14 = MULTIPLY(z3 + z4, - FIX(0.657217813)); /* -c9 */
tmp12 += tmp14;
tmp13 += tmp14;
tmp15 = MULTIPLY(tmp15, FIX(0.338443458)); /* c11 */
tmp14 = tmp15 + MULTIPLY(z1, FIX(0.318774355)) - /* c9-c11 */
MULTIPLY(z2, FIX(0.466105296)); /* c1-c7 */
z1 = MULTIPLY(z3 - z2, FIX(0.937797057)); /* c7 */
tmp14 += z1;
tmp15 += z1 + MULTIPLY(z3, FIX(0.384515595)) - /* c3-c7 */
MULTIPLY(z4, FIX(1.742345811)); /* c1+c11 */
/* Final output stage */
wsptr[8*0] = (int) RIGHT_SHIFT(tmp20 + tmp10, CONST_BITS-PASS1_BITS);
wsptr[8*12] = (int) RIGHT_SHIFT(tmp20 - tmp10, CONST_BITS-PASS1_BITS);
wsptr[8*1] = (int) RIGHT_SHIFT(tmp21 + tmp11, CONST_BITS-PASS1_BITS);
wsptr[8*11] = (int) RIGHT_SHIFT(tmp21 - tmp11, CONST_BITS-PASS1_BITS);
wsptr[8*2] = (int) RIGHT_SHIFT(tmp22 + tmp12, CONST_BITS-PASS1_BITS);
wsptr[8*10] = (int) RIGHT_SHIFT(tmp22 - tmp12, CONST_BITS-PASS1_BITS);
wsptr[8*3] = (int) RIGHT_SHIFT(tmp23 + tmp13, CONST_BITS-PASS1_BITS);
wsptr[8*9] = (int) RIGHT_SHIFT(tmp23 - tmp13, CONST_BITS-PASS1_BITS);
wsptr[8*4] = (int) RIGHT_SHIFT(tmp24 + tmp14, CONST_BITS-PASS1_BITS);
wsptr[8*8] = (int) RIGHT_SHIFT(tmp24 - tmp14, CONST_BITS-PASS1_BITS);
wsptr[8*5] = (int) RIGHT_SHIFT(tmp25 + tmp15, CONST_BITS-PASS1_BITS);
wsptr[8*7] = (int) RIGHT_SHIFT(tmp25 - tmp15, CONST_BITS-PASS1_BITS);
wsptr[8*6] = (int) RIGHT_SHIFT(tmp26, CONST_BITS-PASS1_BITS);
}
/* Pass 2: process 13 rows from work array, store into output array. */
wsptr = workspace;
for (ctr = 0; ctr < 13; ctr++) {
outptr = output_buf[ctr] + output_col;
/* Even part */
/* Add fudge factor here for final descale. */
z1 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
z1 <<= CONST_BITS;
z2 = (INT32) wsptr[2];
z3 = (INT32) wsptr[4];
z4 = (INT32) wsptr[6];
tmp10 = z3 + z4;
tmp11 = z3 - z4;
tmp12 = MULTIPLY(tmp10, FIX(1.155388986)); /* (c4+c6)/2 */
tmp13 = MULTIPLY(tmp11, FIX(0.096834934)) + z1; /* (c4-c6)/2 */
tmp20 = MULTIPLY(z2, FIX(1.373119086)) + tmp12 + tmp13; /* c2 */
tmp22 = MULTIPLY(z2, FIX(0.501487041)) - tmp12 + tmp13; /* c10 */
tmp12 = MULTIPLY(tmp10, FIX(0.316450131)); /* (c8-c12)/2 */
tmp13 = MULTIPLY(tmp11, FIX(0.486914739)) + z1; /* (c8+c12)/2 */
tmp21 = MULTIPLY(z2, FIX(1.058554052)) - tmp12 + tmp13; /* c6 */
tmp25 = MULTIPLY(z2, - FIX(1.252223920)) + tmp12 + tmp13; /* c4 */
tmp12 = MULTIPLY(tmp10, FIX(0.435816023)); /* (c2-c10)/2 */
tmp13 = MULTIPLY(tmp11, FIX(0.937303064)) - z1; /* (c2+c10)/2 */
tmp23 = MULTIPLY(z2, - FIX(0.170464608)) - tmp12 - tmp13; /* c12 */
tmp24 = MULTIPLY(z2, - FIX(0.803364869)) + tmp12 - tmp13; /* c8 */
tmp26 = MULTIPLY(tmp11 - z2, FIX(1.414213562)) + z1; /* c0 */
/* Odd part */
z1 = (INT32) wsptr[1];
z2 = (INT32) wsptr[3];
z3 = (INT32) wsptr[5];
z4 = (INT32) wsptr[7];
tmp11 = MULTIPLY(z1 + z2, FIX(1.322312651)); /* c3 */
tmp12 = MULTIPLY(z1 + z3, FIX(1.163874945)); /* c5 */
tmp15 = z1 + z4;
tmp13 = MULTIPLY(tmp15, FIX(0.937797057)); /* c7 */
tmp10 = tmp11 + tmp12 + tmp13 -
MULTIPLY(z1, FIX(2.020082300)); /* c7+c5+c3-c1 */
tmp14 = MULTIPLY(z2 + z3, - FIX(0.338443458)); /* -c11 */
tmp11 += tmp14 + MULTIPLY(z2, FIX(0.837223564)); /* c5+c9+c11-c3 */
tmp12 += tmp14 - MULTIPLY(z3, FIX(1.572116027)); /* c1+c5-c9-c11 */
tmp14 = MULTIPLY(z2 + z4, - FIX(1.163874945)); /* -c5 */
tmp11 += tmp14;
tmp13 += tmp14 + MULTIPLY(z4, FIX(2.205608352)); /* c3+c5+c9-c7 */
tmp14 = MULTIPLY(z3 + z4, - FIX(0.657217813)); /* -c9 */
tmp12 += tmp14;
tmp13 += tmp14;
tmp15 = MULTIPLY(tmp15, FIX(0.338443458)); /* c11 */
tmp14 = tmp15 + MULTIPLY(z1, FIX(0.318774355)) - /* c9-c11 */
MULTIPLY(z2, FIX(0.466105296)); /* c1-c7 */
z1 = MULTIPLY(z3 - z2, FIX(0.937797057)); /* c7 */
tmp14 += z1;
tmp15 += z1 + MULTIPLY(z3, FIX(0.384515595)) - /* c3-c7 */
MULTIPLY(z4, FIX(1.742345811)); /* c1+c11 */
/* Final output stage */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp20 + tmp10,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[12] = range_limit[(int) RIGHT_SHIFT(tmp20 - tmp10,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp21 + tmp11,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[11] = range_limit[(int) RIGHT_SHIFT(tmp21 - tmp11,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp22 + tmp12,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[10] = range_limit[(int) RIGHT_SHIFT(tmp22 - tmp12,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp23 + tmp13,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[9] = range_limit[(int) RIGHT_SHIFT(tmp23 - tmp13,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp24 + tmp14,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[8] = range_limit[(int) RIGHT_SHIFT(tmp24 - tmp14,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp25 + tmp15,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp25 - tmp15,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp26,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
wsptr += 8; /* advance pointer to next row */
}
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a 14x14 output block.
*
* Optimized algorithm with 20 multiplications in the 1-D kernel.
* cK represents sqrt(2) * cos(K*pi/28).
*/
void
jpeg_idct_14x14 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp10, tmp11, tmp12, tmp13, tmp14, tmp15, tmp16;
INT32 tmp20, tmp21, tmp22, tmp23, tmp24, tmp25, tmp26;
INT32 z1, z2, z3, z4;
JCOEFPTR inptr;
ISLOW_MULT_TYPE * quantptr;
int * wsptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
int workspace[8*14]; /* buffers data between passes */
SHIFT_TEMPS
/* Pass 1: process columns from input, store into work array. */
inptr = coef_block;
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
wsptr = workspace;
for (ctr = 0; ctr < 8; ctr++, inptr++, quantptr++, wsptr++) {
/* Even part */
z1 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
z1 <<= CONST_BITS;
/* Add fudge factor here for final descale. */
z1 += ONE << (CONST_BITS-PASS1_BITS-1);
z4 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
z2 = MULTIPLY(z4, FIX(1.274162392)); /* c4 */
z3 = MULTIPLY(z4, FIX(0.314692123)); /* c12 */
z4 = MULTIPLY(z4, FIX(0.881747734)); /* c8 */
tmp10 = z1 + z2;
tmp11 = z1 + z3;
tmp12 = z1 - z4;
tmp23 = RIGHT_SHIFT(z1 - ((z2 + z3 - z4) << 1), /* c0 = (c4+c12-c8)*2 */
CONST_BITS-PASS1_BITS);
z1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
z2 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
z3 = MULTIPLY(z1 + z2, FIX(1.105676686)); /* c6 */
tmp13 = z3 + MULTIPLY(z1, FIX(0.273079590)); /* c2-c6 */
tmp14 = z3 - MULTIPLY(z2, FIX(1.719280954)); /* c6+c10 */
tmp15 = MULTIPLY(z1, FIX(0.613604268)) - /* c10 */
MULTIPLY(z2, FIX(1.378756276)); /* c2 */
tmp20 = tmp10 + tmp13;
tmp26 = tmp10 - tmp13;
tmp21 = tmp11 + tmp14;
tmp25 = tmp11 - tmp14;
tmp22 = tmp12 + tmp15;
tmp24 = tmp12 - tmp15;
/* Odd part */
z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
z4 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
tmp13 = z4 << CONST_BITS;
tmp14 = z1 + z3;
tmp11 = MULTIPLY(z1 + z2, FIX(1.334852607)); /* c3 */
tmp12 = MULTIPLY(tmp14, FIX(1.197448846)); /* c5 */
tmp10 = tmp11 + tmp12 + tmp13 - MULTIPLY(z1, FIX(1.126980169)); /* c3+c5-c1 */
tmp14 = MULTIPLY(tmp14, FIX(0.752406978)); /* c9 */
tmp16 = tmp14 - MULTIPLY(z1, FIX(1.061150426)); /* c9+c11-c13 */
z1 -= z2;
tmp15 = MULTIPLY(z1, FIX(0.467085129)) - tmp13; /* c11 */
tmp16 += tmp15;
z1 += z4;
z4 = MULTIPLY(z2 + z3, - FIX(0.158341681)) - tmp13; /* -c13 */
tmp11 += z4 - MULTIPLY(z2, FIX(0.424103948)); /* c3-c9-c13 */
tmp12 += z4 - MULTIPLY(z3, FIX(2.373959773)); /* c3+c5-c13 */
z4 = MULTIPLY(z3 - z2, FIX(1.405321284)); /* c1 */
tmp14 += z4 + tmp13 - MULTIPLY(z3, FIX(1.6906431334)); /* c1+c9-c11 */
tmp15 += z4 + MULTIPLY(z2, FIX(0.674957567)); /* c1+c11-c5 */
tmp13 = (z1 - z3) << PASS1_BITS;
/* Final output stage */
wsptr[8*0] = (int) RIGHT_SHIFT(tmp20 + tmp10, CONST_BITS-PASS1_BITS);
wsptr[8*13] = (int) RIGHT_SHIFT(tmp20 - tmp10, CONST_BITS-PASS1_BITS);
wsptr[8*1] = (int) RIGHT_SHIFT(tmp21 + tmp11, CONST_BITS-PASS1_BITS);
wsptr[8*12] = (int) RIGHT_SHIFT(tmp21 - tmp11, CONST_BITS-PASS1_BITS);
wsptr[8*2] = (int) RIGHT_SHIFT(tmp22 + tmp12, CONST_BITS-PASS1_BITS);
wsptr[8*11] = (int) RIGHT_SHIFT(tmp22 - tmp12, CONST_BITS-PASS1_BITS);
wsptr[8*3] = (int) (tmp23 + tmp13);
wsptr[8*10] = (int) (tmp23 - tmp13);
wsptr[8*4] = (int) RIGHT_SHIFT(tmp24 + tmp14, CONST_BITS-PASS1_BITS);
wsptr[8*9] = (int) RIGHT_SHIFT(tmp24 - tmp14, CONST_BITS-PASS1_BITS);
wsptr[8*5] = (int) RIGHT_SHIFT(tmp25 + tmp15, CONST_BITS-PASS1_BITS);
wsptr[8*8] = (int) RIGHT_SHIFT(tmp25 - tmp15, CONST_BITS-PASS1_BITS);
wsptr[8*6] = (int) RIGHT_SHIFT(tmp26 + tmp16, CONST_BITS-PASS1_BITS);
wsptr[8*7] = (int) RIGHT_SHIFT(tmp26 - tmp16, CONST_BITS-PASS1_BITS);
}
/* Pass 2: process 14 rows from work array, store into output array. */
wsptr = workspace;
for (ctr = 0; ctr < 14; ctr++) {
outptr = output_buf[ctr] + output_col;
/* Even part */
/* Add fudge factor here for final descale. */
z1 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
z1 <<= CONST_BITS;
z4 = (INT32) wsptr[4];
z2 = MULTIPLY(z4, FIX(1.274162392)); /* c4 */
z3 = MULTIPLY(z4, FIX(0.314692123)); /* c12 */
z4 = MULTIPLY(z4, FIX(0.881747734)); /* c8 */
tmp10 = z1 + z2;
tmp11 = z1 + z3;
tmp12 = z1 - z4;
tmp23 = z1 - ((z2 + z3 - z4) << 1); /* c0 = (c4+c12-c8)*2 */
z1 = (INT32) wsptr[2];
z2 = (INT32) wsptr[6];
z3 = MULTIPLY(z1 + z2, FIX(1.105676686)); /* c6 */
tmp13 = z3 + MULTIPLY(z1, FIX(0.273079590)); /* c2-c6 */
tmp14 = z3 - MULTIPLY(z2, FIX(1.719280954)); /* c6+c10 */
tmp15 = MULTIPLY(z1, FIX(0.613604268)) - /* c10 */
MULTIPLY(z2, FIX(1.378756276)); /* c2 */
tmp20 = tmp10 + tmp13;
tmp26 = tmp10 - tmp13;
tmp21 = tmp11 + tmp14;
tmp25 = tmp11 - tmp14;
tmp22 = tmp12 + tmp15;
tmp24 = tmp12 - tmp15;
/* Odd part */
z1 = (INT32) wsptr[1];
z2 = (INT32) wsptr[3];
z3 = (INT32) wsptr[5];
z4 = (INT32) wsptr[7];
z4 <<= CONST_BITS;
tmp14 = z1 + z3;
tmp11 = MULTIPLY(z1 + z2, FIX(1.334852607)); /* c3 */
tmp12 = MULTIPLY(tmp14, FIX(1.197448846)); /* c5 */
tmp10 = tmp11 + tmp12 + z4 - MULTIPLY(z1, FIX(1.126980169)); /* c3+c5-c1 */
tmp14 = MULTIPLY(tmp14, FIX(0.752406978)); /* c9 */
tmp16 = tmp14 - MULTIPLY(z1, FIX(1.061150426)); /* c9+c11-c13 */
z1 -= z2;
tmp15 = MULTIPLY(z1, FIX(0.467085129)) - z4; /* c11 */
tmp16 += tmp15;
tmp13 = MULTIPLY(z2 + z3, - FIX(0.158341681)) - z4; /* -c13 */
tmp11 += tmp13 - MULTIPLY(z2, FIX(0.424103948)); /* c3-c9-c13 */
tmp12 += tmp13 - MULTIPLY(z3, FIX(2.373959773)); /* c3+c5-c13 */
tmp13 = MULTIPLY(z3 - z2, FIX(1.405321284)); /* c1 */
tmp14 += tmp13 + z4 - MULTIPLY(z3, FIX(1.6906431334)); /* c1+c9-c11 */
tmp15 += tmp13 + MULTIPLY(z2, FIX(0.674957567)); /* c1+c11-c5 */
tmp13 = ((z1 - z3) << CONST_BITS) + z4;
/* Final output stage */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp20 + tmp10,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[13] = range_limit[(int) RIGHT_SHIFT(tmp20 - tmp10,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp21 + tmp11,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[12] = range_limit[(int) RIGHT_SHIFT(tmp21 - tmp11,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp22 + tmp12,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[11] = range_limit[(int) RIGHT_SHIFT(tmp22 - tmp12,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp23 + tmp13,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[10] = range_limit[(int) RIGHT_SHIFT(tmp23 - tmp13,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp24 + tmp14,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[9] = range_limit[(int) RIGHT_SHIFT(tmp24 - tmp14,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp25 + tmp15,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[8] = range_limit[(int) RIGHT_SHIFT(tmp25 - tmp15,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp26 + tmp16,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp26 - tmp16,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
wsptr += 8; /* advance pointer to next row */
}
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a 15x15 output block.
*
* Optimized algorithm with 22 multiplications in the 1-D kernel.
* cK represents sqrt(2) * cos(K*pi/30).
*/
void
jpeg_idct_15x15 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp10, tmp11, tmp12, tmp13, tmp14, tmp15, tmp16;
INT32 tmp20, tmp21, tmp22, tmp23, tmp24, tmp25, tmp26, tmp27;
INT32 z1, z2, z3, z4;
JCOEFPTR inptr;
ISLOW_MULT_TYPE * quantptr;
int * wsptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
int workspace[8*15]; /* buffers data between passes */
SHIFT_TEMPS
/* Pass 1: process columns from input, store into work array. */
inptr = coef_block;
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
wsptr = workspace;
for (ctr = 0; ctr < 8; ctr++, inptr++, quantptr++, wsptr++) {
/* Even part */
z1 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
z1 <<= CONST_BITS;
/* Add fudge factor here for final descale. */
z1 += ONE << (CONST_BITS-PASS1_BITS-1);
z2 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
z3 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
z4 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
tmp10 = MULTIPLY(z4, FIX(0.437016024)); /* c12 */
tmp11 = MULTIPLY(z4, FIX(1.144122806)); /* c6 */
tmp12 = z1 - tmp10;
tmp13 = z1 + tmp11;
z1 -= (tmp11 - tmp10) << 1; /* c0 = (c6-c12)*2 */
z4 = z2 - z3;
z3 += z2;
tmp10 = MULTIPLY(z3, FIX(1.337628990)); /* (c2+c4)/2 */
tmp11 = MULTIPLY(z4, FIX(0.045680613)); /* (c2-c4)/2 */
z2 = MULTIPLY(z2, FIX(1.439773946)); /* c4+c14 */
tmp20 = tmp13 + tmp10 + tmp11;
tmp23 = tmp12 - tmp10 + tmp11 + z2;
tmp10 = MULTIPLY(z3, FIX(0.547059574)); /* (c8+c14)/2 */
tmp11 = MULTIPLY(z4, FIX(0.399234004)); /* (c8-c14)/2 */
tmp25 = tmp13 - tmp10 - tmp11;
tmp26 = tmp12 + tmp10 - tmp11 - z2;
tmp10 = MULTIPLY(z3, FIX(0.790569415)); /* (c6+c12)/2 */
tmp11 = MULTIPLY(z4, FIX(0.353553391)); /* (c6-c12)/2 */
tmp21 = tmp12 + tmp10 + tmp11;
tmp24 = tmp13 - tmp10 + tmp11;
tmp11 += tmp11;
tmp22 = z1 + tmp11; /* c10 = c6-c12 */
tmp27 = z1 - tmp11 - tmp11; /* c0 = (c6-c12)*2 */
/* Odd part */
z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
z4 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
z3 = MULTIPLY(z4, FIX(1.224744871)); /* c5 */
z4 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
tmp13 = z2 - z4;
tmp15 = MULTIPLY(z1 + tmp13, FIX(0.831253876)); /* c9 */
tmp11 = tmp15 + MULTIPLY(z1, FIX(0.513743148)); /* c3-c9 */
tmp14 = tmp15 - MULTIPLY(tmp13, FIX(2.176250899)); /* c3+c9 */
tmp13 = MULTIPLY(z2, - FIX(0.831253876)); /* -c9 */
tmp15 = MULTIPLY(z2, - FIX(1.344997024)); /* -c3 */
z2 = z1 - z4;
tmp12 = z3 + MULTIPLY(z2, FIX(1.406466353)); /* c1 */
tmp10 = tmp12 + MULTIPLY(z4, FIX(2.457431844)) - tmp15; /* c1+c7 */
tmp16 = tmp12 - MULTIPLY(z1, FIX(1.112434820)) + tmp13; /* c1-c13 */
tmp12 = MULTIPLY(z2, FIX(1.224744871)) - z3; /* c5 */
z2 = MULTIPLY(z1 + z4, FIX(0.575212477)); /* c11 */
tmp13 += z2 + MULTIPLY(z1, FIX(0.475753014)) - z3; /* c7-c11 */
tmp15 += z2 - MULTIPLY(z4, FIX(0.869244010)) + z3; /* c11+c13 */
/* Final output stage */
wsptr[8*0] = (int) RIGHT_SHIFT(tmp20 + tmp10, CONST_BITS-PASS1_BITS);
wsptr[8*14] = (int) RIGHT_SHIFT(tmp20 - tmp10, CONST_BITS-PASS1_BITS);
wsptr[8*1] = (int) RIGHT_SHIFT(tmp21 + tmp11, CONST_BITS-PASS1_BITS);
wsptr[8*13] = (int) RIGHT_SHIFT(tmp21 - tmp11, CONST_BITS-PASS1_BITS);
wsptr[8*2] = (int) RIGHT_SHIFT(tmp22 + tmp12, CONST_BITS-PASS1_BITS);
wsptr[8*12] = (int) RIGHT_SHIFT(tmp22 - tmp12, CONST_BITS-PASS1_BITS);
wsptr[8*3] = (int) RIGHT_SHIFT(tmp23 + tmp13, CONST_BITS-PASS1_BITS);
wsptr[8*11] = (int) RIGHT_SHIFT(tmp23 - tmp13, CONST_BITS-PASS1_BITS);
wsptr[8*4] = (int) RIGHT_SHIFT(tmp24 + tmp14, CONST_BITS-PASS1_BITS);
wsptr[8*10] = (int) RIGHT_SHIFT(tmp24 - tmp14, CONST_BITS-PASS1_BITS);
wsptr[8*5] = (int) RIGHT_SHIFT(tmp25 + tmp15, CONST_BITS-PASS1_BITS);
wsptr[8*9] = (int) RIGHT_SHIFT(tmp25 - tmp15, CONST_BITS-PASS1_BITS);
wsptr[8*6] = (int) RIGHT_SHIFT(tmp26 + tmp16, CONST_BITS-PASS1_BITS);
wsptr[8*8] = (int) RIGHT_SHIFT(tmp26 - tmp16, CONST_BITS-PASS1_BITS);
wsptr[8*7] = (int) RIGHT_SHIFT(tmp27, CONST_BITS-PASS1_BITS);
}
/* Pass 2: process 15 rows from work array, store into output array. */
wsptr = workspace;
for (ctr = 0; ctr < 15; ctr++) {
outptr = output_buf[ctr] + output_col;
/* Even part */
/* Add fudge factor here for final descale. */
z1 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
z1 <<= CONST_BITS;
z2 = (INT32) wsptr[2];
z3 = (INT32) wsptr[4];
z4 = (INT32) wsptr[6];
tmp10 = MULTIPLY(z4, FIX(0.437016024)); /* c12 */
tmp11 = MULTIPLY(z4, FIX(1.144122806)); /* c6 */
tmp12 = z1 - tmp10;
tmp13 = z1 + tmp11;
z1 -= (tmp11 - tmp10) << 1; /* c0 = (c6-c12)*2 */
z4 = z2 - z3;
z3 += z2;
tmp10 = MULTIPLY(z3, FIX(1.337628990)); /* (c2+c4)/2 */
tmp11 = MULTIPLY(z4, FIX(0.045680613)); /* (c2-c4)/2 */
z2 = MULTIPLY(z2, FIX(1.439773946)); /* c4+c14 */
tmp20 = tmp13 + tmp10 + tmp11;
tmp23 = tmp12 - tmp10 + tmp11 + z2;
tmp10 = MULTIPLY(z3, FIX(0.547059574)); /* (c8+c14)/2 */
tmp11 = MULTIPLY(z4, FIX(0.399234004)); /* (c8-c14)/2 */
tmp25 = tmp13 - tmp10 - tmp11;
tmp26 = tmp12 + tmp10 - tmp11 - z2;
tmp10 = MULTIPLY(z3, FIX(0.790569415)); /* (c6+c12)/2 */
tmp11 = MULTIPLY(z4, FIX(0.353553391)); /* (c6-c12)/2 */
tmp21 = tmp12 + tmp10 + tmp11;
tmp24 = tmp13 - tmp10 + tmp11;
tmp11 += tmp11;
tmp22 = z1 + tmp11; /* c10 = c6-c12 */
tmp27 = z1 - tmp11 - tmp11; /* c0 = (c6-c12)*2 */
/* Odd part */
z1 = (INT32) wsptr[1];
z2 = (INT32) wsptr[3];
z4 = (INT32) wsptr[5];
z3 = MULTIPLY(z4, FIX(1.224744871)); /* c5 */
z4 = (INT32) wsptr[7];
tmp13 = z2 - z4;
tmp15 = MULTIPLY(z1 + tmp13, FIX(0.831253876)); /* c9 */
tmp11 = tmp15 + MULTIPLY(z1, FIX(0.513743148)); /* c3-c9 */
tmp14 = tmp15 - MULTIPLY(tmp13, FIX(2.176250899)); /* c3+c9 */
tmp13 = MULTIPLY(z2, - FIX(0.831253876)); /* -c9 */
tmp15 = MULTIPLY(z2, - FIX(1.344997024)); /* -c3 */
z2 = z1 - z4;
tmp12 = z3 + MULTIPLY(z2, FIX(1.406466353)); /* c1 */
tmp10 = tmp12 + MULTIPLY(z4, FIX(2.457431844)) - tmp15; /* c1+c7 */
tmp16 = tmp12 - MULTIPLY(z1, FIX(1.112434820)) + tmp13; /* c1-c13 */
tmp12 = MULTIPLY(z2, FIX(1.224744871)) - z3; /* c5 */
z2 = MULTIPLY(z1 + z4, FIX(0.575212477)); /* c11 */
tmp13 += z2 + MULTIPLY(z1, FIX(0.475753014)) - z3; /* c7-c11 */
tmp15 += z2 - MULTIPLY(z4, FIX(0.869244010)) + z3; /* c11+c13 */
/* Final output stage */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp20 + tmp10,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[14] = range_limit[(int) RIGHT_SHIFT(tmp20 - tmp10,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp21 + tmp11,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[13] = range_limit[(int) RIGHT_SHIFT(tmp21 - tmp11,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp22 + tmp12,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[12] = range_limit[(int) RIGHT_SHIFT(tmp22 - tmp12,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp23 + tmp13,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[11] = range_limit[(int) RIGHT_SHIFT(tmp23 - tmp13,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp24 + tmp14,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[10] = range_limit[(int) RIGHT_SHIFT(tmp24 - tmp14,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp25 + tmp15,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[9] = range_limit[(int) RIGHT_SHIFT(tmp25 - tmp15,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp26 + tmp16,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[8] = range_limit[(int) RIGHT_SHIFT(tmp26 - tmp16,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp27,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
wsptr += 8; /* advance pointer to next row */
}
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a 16x16 output block.
*
* Optimized algorithm with 28 multiplications in the 1-D kernel.
* cK represents sqrt(2) * cos(K*pi/32).
*/
void
jpeg_idct_16x16 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp0, tmp1, tmp2, tmp3, tmp10, tmp11, tmp12, tmp13;
INT32 tmp20, tmp21, tmp22, tmp23, tmp24, tmp25, tmp26, tmp27;
INT32 z1, z2, z3, z4;
JCOEFPTR inptr;
ISLOW_MULT_TYPE * quantptr;
int * wsptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
int workspace[8*16]; /* buffers data between passes */
SHIFT_TEMPS
/* Pass 1: process columns from input, store into work array. */
inptr = coef_block;
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
wsptr = workspace;
for (ctr = 0; ctr < 8; ctr++, inptr++, quantptr++, wsptr++) {
/* Even part */
tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
tmp0 <<= CONST_BITS;
/* Add fudge factor here for final descale. */
tmp0 += 1 << (CONST_BITS-PASS1_BITS-1);
z1 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
tmp1 = MULTIPLY(z1, FIX(1.306562965)); /* c4[16] = c2[8] */
tmp2 = MULTIPLY(z1, FIX_0_541196100); /* c12[16] = c6[8] */
tmp10 = tmp0 + tmp1;
tmp11 = tmp0 - tmp1;
tmp12 = tmp0 + tmp2;
tmp13 = tmp0 - tmp2;
z1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
z2 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
z3 = z1 - z2;
z4 = MULTIPLY(z3, FIX(0.275899379)); /* c14[16] = c7[8] */
z3 = MULTIPLY(z3, FIX(1.387039845)); /* c2[16] = c1[8] */
tmp0 = z3 + MULTIPLY(z2, FIX_2_562915447); /* (c6+c2)[16] = (c3+c1)[8] */
tmp1 = z4 + MULTIPLY(z1, FIX_0_899976223); /* (c6-c14)[16] = (c3-c7)[8] */
tmp2 = z3 - MULTIPLY(z1, FIX(0.601344887)); /* (c2-c10)[16] = (c1-c5)[8] */
tmp3 = z4 - MULTIPLY(z2, FIX(0.509795579)); /* (c10-c14)[16] = (c5-c7)[8] */
tmp20 = tmp10 + tmp0;
tmp27 = tmp10 - tmp0;
tmp21 = tmp12 + tmp1;
tmp26 = tmp12 - tmp1;
tmp22 = tmp13 + tmp2;
tmp25 = tmp13 - tmp2;
tmp23 = tmp11 + tmp3;
tmp24 = tmp11 - tmp3;
/* Odd part */
z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
z4 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
tmp11 = z1 + z3;
tmp1 = MULTIPLY(z1 + z2, FIX(1.353318001)); /* c3 */
tmp2 = MULTIPLY(tmp11, FIX(1.247225013)); /* c5 */
tmp3 = MULTIPLY(z1 + z4, FIX(1.093201867)); /* c7 */
tmp10 = MULTIPLY(z1 - z4, FIX(0.897167586)); /* c9 */
tmp11 = MULTIPLY(tmp11, FIX(0.666655658)); /* c11 */
tmp12 = MULTIPLY(z1 - z2, FIX(0.410524528)); /* c13 */
tmp0 = tmp1 + tmp2 + tmp3 -
MULTIPLY(z1, FIX(2.286341144)); /* c7+c5+c3-c1 */
tmp13 = tmp10 + tmp11 + tmp12 -
MULTIPLY(z1, FIX(1.835730603)); /* c9+c11+c13-c15 */
z1 = MULTIPLY(z2 + z3, FIX(0.138617169)); /* c15 */
tmp1 += z1 + MULTIPLY(z2, FIX(0.071888074)); /* c9+c11-c3-c15 */
tmp2 += z1 - MULTIPLY(z3, FIX(1.125726048)); /* c5+c7+c15-c3 */
z1 = MULTIPLY(z3 - z2, FIX(1.407403738)); /* c1 */
tmp11 += z1 - MULTIPLY(z3, FIX(0.766367282)); /* c1+c11-c9-c13 */
tmp12 += z1 + MULTIPLY(z2, FIX(1.971951411)); /* c1+c5+c13-c7 */
z2 += z4;
z1 = MULTIPLY(z2, - FIX(0.666655658)); /* -c11 */
tmp1 += z1;
tmp3 += z1 + MULTIPLY(z4, FIX(1.065388962)); /* c3+c11+c15-c7 */
z2 = MULTIPLY(z2, - FIX(1.247225013)); /* -c5 */
tmp10 += z2 + MULTIPLY(z4, FIX(3.141271809)); /* c1+c5+c9-c13 */
tmp12 += z2;
z2 = MULTIPLY(z3 + z4, - FIX(1.353318001)); /* -c3 */
tmp2 += z2;
tmp3 += z2;
z2 = MULTIPLY(z4 - z3, FIX(0.410524528)); /* c13 */
tmp10 += z2;
tmp11 += z2;
/* Final output stage */
wsptr[8*0] = (int) RIGHT_SHIFT(tmp20 + tmp0, CONST_BITS-PASS1_BITS);
wsptr[8*15] = (int) RIGHT_SHIFT(tmp20 - tmp0, CONST_BITS-PASS1_BITS);
wsptr[8*1] = (int) RIGHT_SHIFT(tmp21 + tmp1, CONST_BITS-PASS1_BITS);
wsptr[8*14] = (int) RIGHT_SHIFT(tmp21 - tmp1, CONST_BITS-PASS1_BITS);
wsptr[8*2] = (int) RIGHT_SHIFT(tmp22 + tmp2, CONST_BITS-PASS1_BITS);
wsptr[8*13] = (int) RIGHT_SHIFT(tmp22 - tmp2, CONST_BITS-PASS1_BITS);
wsptr[8*3] = (int) RIGHT_SHIFT(tmp23 + tmp3, CONST_BITS-PASS1_BITS);
wsptr[8*12] = (int) RIGHT_SHIFT(tmp23 - tmp3, CONST_BITS-PASS1_BITS);
wsptr[8*4] = (int) RIGHT_SHIFT(tmp24 + tmp10, CONST_BITS-PASS1_BITS);
wsptr[8*11] = (int) RIGHT_SHIFT(tmp24 - tmp10, CONST_BITS-PASS1_BITS);
wsptr[8*5] = (int) RIGHT_SHIFT(tmp25 + tmp11, CONST_BITS-PASS1_BITS);
wsptr[8*10] = (int) RIGHT_SHIFT(tmp25 - tmp11, CONST_BITS-PASS1_BITS);
wsptr[8*6] = (int) RIGHT_SHIFT(tmp26 + tmp12, CONST_BITS-PASS1_BITS);
wsptr[8*9] = (int) RIGHT_SHIFT(tmp26 - tmp12, CONST_BITS-PASS1_BITS);
wsptr[8*7] = (int) RIGHT_SHIFT(tmp27 + tmp13, CONST_BITS-PASS1_BITS);
wsptr[8*8] = (int) RIGHT_SHIFT(tmp27 - tmp13, CONST_BITS-PASS1_BITS);
}
/* Pass 2: process 16 rows from work array, store into output array. */
wsptr = workspace;
for (ctr = 0; ctr < 16; ctr++) {
outptr = output_buf[ctr] + output_col;
/* Even part */
/* Add fudge factor here for final descale. */
tmp0 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
tmp0 <<= CONST_BITS;
z1 = (INT32) wsptr[4];
tmp1 = MULTIPLY(z1, FIX(1.306562965)); /* c4[16] = c2[8] */
tmp2 = MULTIPLY(z1, FIX_0_541196100); /* c12[16] = c6[8] */
tmp10 = tmp0 + tmp1;
tmp11 = tmp0 - tmp1;
tmp12 = tmp0 + tmp2;
tmp13 = tmp0 - tmp2;
z1 = (INT32) wsptr[2];
z2 = (INT32) wsptr[6];
z3 = z1 - z2;
z4 = MULTIPLY(z3, FIX(0.275899379)); /* c14[16] = c7[8] */
z3 = MULTIPLY(z3, FIX(1.387039845)); /* c2[16] = c1[8] */
tmp0 = z3 + MULTIPLY(z2, FIX_2_562915447); /* (c6+c2)[16] = (c3+c1)[8] */
tmp1 = z4 + MULTIPLY(z1, FIX_0_899976223); /* (c6-c14)[16] = (c3-c7)[8] */
tmp2 = z3 - MULTIPLY(z1, FIX(0.601344887)); /* (c2-c10)[16] = (c1-c5)[8] */
tmp3 = z4 - MULTIPLY(z2, FIX(0.509795579)); /* (c10-c14)[16] = (c5-c7)[8] */
tmp20 = tmp10 + tmp0;
tmp27 = tmp10 - tmp0;
tmp21 = tmp12 + tmp1;
tmp26 = tmp12 - tmp1;
tmp22 = tmp13 + tmp2;
tmp25 = tmp13 - tmp2;
tmp23 = tmp11 + tmp3;
tmp24 = tmp11 - tmp3;
/* Odd part */
z1 = (INT32) wsptr[1];
z2 = (INT32) wsptr[3];
z3 = (INT32) wsptr[5];
z4 = (INT32) wsptr[7];
tmp11 = z1 + z3;
tmp1 = MULTIPLY(z1 + z2, FIX(1.353318001)); /* c3 */
tmp2 = MULTIPLY(tmp11, FIX(1.247225013)); /* c5 */
tmp3 = MULTIPLY(z1 + z4, FIX(1.093201867)); /* c7 */
tmp10 = MULTIPLY(z1 - z4, FIX(0.897167586)); /* c9 */
tmp11 = MULTIPLY(tmp11, FIX(0.666655658)); /* c11 */
tmp12 = MULTIPLY(z1 - z2, FIX(0.410524528)); /* c13 */
tmp0 = tmp1 + tmp2 + tmp3 -
MULTIPLY(z1, FIX(2.286341144)); /* c7+c5+c3-c1 */
tmp13 = tmp10 + tmp11 + tmp12 -
MULTIPLY(z1, FIX(1.835730603)); /* c9+c11+c13-c15 */
z1 = MULTIPLY(z2 + z3, FIX(0.138617169)); /* c15 */
tmp1 += z1 + MULTIPLY(z2, FIX(0.071888074)); /* c9+c11-c3-c15 */
tmp2 += z1 - MULTIPLY(z3, FIX(1.125726048)); /* c5+c7+c15-c3 */
z1 = MULTIPLY(z3 - z2, FIX(1.407403738)); /* c1 */
tmp11 += z1 - MULTIPLY(z3, FIX(0.766367282)); /* c1+c11-c9-c13 */
tmp12 += z1 + MULTIPLY(z2, FIX(1.971951411)); /* c1+c5+c13-c7 */
z2 += z4;
z1 = MULTIPLY(z2, - FIX(0.666655658)); /* -c11 */
tmp1 += z1;
tmp3 += z1 + MULTIPLY(z4, FIX(1.065388962)); /* c3+c11+c15-c7 */
z2 = MULTIPLY(z2, - FIX(1.247225013)); /* -c5 */
tmp10 += z2 + MULTIPLY(z4, FIX(3.141271809)); /* c1+c5+c9-c13 */
tmp12 += z2;
z2 = MULTIPLY(z3 + z4, - FIX(1.353318001)); /* -c3 */
tmp2 += z2;
tmp3 += z2;
z2 = MULTIPLY(z4 - z3, FIX(0.410524528)); /* c13 */
tmp10 += z2;
tmp11 += z2;
/* Final output stage */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp20 + tmp0,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[15] = range_limit[(int) RIGHT_SHIFT(tmp20 - tmp0,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp21 + tmp1,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[14] = range_limit[(int) RIGHT_SHIFT(tmp21 - tmp1,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp22 + tmp2,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[13] = range_limit[(int) RIGHT_SHIFT(tmp22 - tmp2,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp23 + tmp3,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[12] = range_limit[(int) RIGHT_SHIFT(tmp23 - tmp3,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp24 + tmp10,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[11] = range_limit[(int) RIGHT_SHIFT(tmp24 - tmp10,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp25 + tmp11,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[10] = range_limit[(int) RIGHT_SHIFT(tmp25 - tmp11,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp26 + tmp12,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[9] = range_limit[(int) RIGHT_SHIFT(tmp26 - tmp12,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp27 + tmp13,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[8] = range_limit[(int) RIGHT_SHIFT(tmp27 - tmp13,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
wsptr += 8; /* advance pointer to next row */
}
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a 16x8 output block.
*
* 8-point IDCT in pass 1 (columns), 16-point in pass 2 (rows).
*/
void
jpeg_idct_16x8 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp0, tmp1, tmp2, tmp3, tmp10, tmp11, tmp12, tmp13;
INT32 tmp20, tmp21, tmp22, tmp23, tmp24, tmp25, tmp26, tmp27;
INT32 z1, z2, z3, z4;
JCOEFPTR inptr;
ISLOW_MULT_TYPE * quantptr;
int * wsptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
int workspace[8*8]; /* buffers data between passes */
SHIFT_TEMPS
/* Pass 1: process columns from input, store into work array. */
/* Note results are scaled up by sqrt(8) compared to a true IDCT; */
/* furthermore, we scale the results by 2**PASS1_BITS. */
inptr = coef_block;
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
wsptr = workspace;
for (ctr = DCTSIZE; ctr > 0; ctr--) {
/* Due to quantization, we will usually find that many of the input
* coefficients are zero, especially the AC terms. We can exploit this
* by short-circuiting the IDCT calculation for any column in which all
* the AC terms are zero. In that case each output is equal to the
* DC coefficient (with scale factor as needed).
* With typical images and quantization tables, half or more of the
* column DCT calculations can be simplified this way.
*/
if (inptr[DCTSIZE*1] == 0 && inptr[DCTSIZE*2] == 0 &&
inptr[DCTSIZE*3] == 0 && inptr[DCTSIZE*4] == 0 &&
inptr[DCTSIZE*5] == 0 && inptr[DCTSIZE*6] == 0 &&
inptr[DCTSIZE*7] == 0) {
/* AC terms all zero */
int dcval = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]) << PASS1_BITS;
wsptr[DCTSIZE*0] = dcval;
wsptr[DCTSIZE*1] = dcval;
wsptr[DCTSIZE*2] = dcval;
wsptr[DCTSIZE*3] = dcval;
wsptr[DCTSIZE*4] = dcval;
wsptr[DCTSIZE*5] = dcval;
wsptr[DCTSIZE*6] = dcval;
wsptr[DCTSIZE*7] = dcval;
inptr++; /* advance pointers to next column */
quantptr++;
wsptr++;
continue;
}
/* Even part: reverse the even part of the forward DCT. */
/* The rotator is sqrt(2)*c(-6). */
z2 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
z3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
z1 = MULTIPLY(z2 + z3, FIX_0_541196100);
tmp2 = z1 + MULTIPLY(z2, FIX_0_765366865);
tmp3 = z1 - MULTIPLY(z3, FIX_1_847759065);
z2 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
z3 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
z2 <<= CONST_BITS;
z3 <<= CONST_BITS;
/* Add fudge factor here for final descale. */
z2 += ONE << (CONST_BITS-PASS1_BITS-1);
tmp0 = z2 + z3;
tmp1 = z2 - z3;
tmp10 = tmp0 + tmp2;
tmp13 = tmp0 - tmp2;
tmp11 = tmp1 + tmp3;
tmp12 = tmp1 - tmp3;
/* Odd part per figure 8; the matrix is unitary and hence its
* transpose is its inverse. i0..i3 are y7,y5,y3,y1 respectively.
*/
tmp0 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
tmp1 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
tmp2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
tmp3 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
z2 = tmp0 + tmp2;
z3 = tmp1 + tmp3;
z1 = MULTIPLY(z2 + z3, FIX_1_175875602); /* sqrt(2) * c3 */
z2 = MULTIPLY(z2, - FIX_1_961570560); /* sqrt(2) * (-c3-c5) */
z3 = MULTIPLY(z3, - FIX_0_390180644); /* sqrt(2) * (c5-c3) */
z2 += z1;
z3 += z1;
z1 = MULTIPLY(tmp0 + tmp3, - FIX_0_899976223); /* sqrt(2) * (c7-c3) */
tmp0 = MULTIPLY(tmp0, FIX_0_298631336); /* sqrt(2) * (-c1+c3+c5-c7) */
tmp3 = MULTIPLY(tmp3, FIX_1_501321110); /* sqrt(2) * ( c1+c3-c5-c7) */
tmp0 += z1 + z2;
tmp3 += z1 + z3;
z1 = MULTIPLY(tmp1 + tmp2, - FIX_2_562915447); /* sqrt(2) * (-c1-c3) */
tmp1 = MULTIPLY(tmp1, FIX_2_053119869); /* sqrt(2) * ( c1+c3-c5+c7) */
tmp2 = MULTIPLY(tmp2, FIX_3_072711026); /* sqrt(2) * ( c1+c3+c5-c7) */
tmp1 += z1 + z3;
tmp2 += z1 + z2;
/* Final output stage: inputs are tmp10..tmp13, tmp0..tmp3 */
wsptr[DCTSIZE*0] = (int) RIGHT_SHIFT(tmp10 + tmp3, CONST_BITS-PASS1_BITS);
wsptr[DCTSIZE*7] = (int) RIGHT_SHIFT(tmp10 - tmp3, CONST_BITS-PASS1_BITS);
wsptr[DCTSIZE*1] = (int) RIGHT_SHIFT(tmp11 + tmp2, CONST_BITS-PASS1_BITS);
wsptr[DCTSIZE*6] = (int) RIGHT_SHIFT(tmp11 - tmp2, CONST_BITS-PASS1_BITS);
wsptr[DCTSIZE*2] = (int) RIGHT_SHIFT(tmp12 + tmp1, CONST_BITS-PASS1_BITS);
wsptr[DCTSIZE*5] = (int) RIGHT_SHIFT(tmp12 - tmp1, CONST_BITS-PASS1_BITS);
wsptr[DCTSIZE*3] = (int) RIGHT_SHIFT(tmp13 + tmp0, CONST_BITS-PASS1_BITS);
wsptr[DCTSIZE*4] = (int) RIGHT_SHIFT(tmp13 - tmp0, CONST_BITS-PASS1_BITS);
inptr++; /* advance pointers to next column */
quantptr++;
wsptr++;
}
/* Pass 2: process 8 rows from work array, store into output array.
* 16-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/32).
*/
wsptr = workspace;
for (ctr = 0; ctr < 8; ctr++) {
outptr = output_buf[ctr] + output_col;
/* Even part */
/* Add fudge factor here for final descale. */
tmp0 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
tmp0 <<= CONST_BITS;
z1 = (INT32) wsptr[4];
tmp1 = MULTIPLY(z1, FIX(1.306562965)); /* c4[16] = c2[8] */
tmp2 = MULTIPLY(z1, FIX_0_541196100); /* c12[16] = c6[8] */
tmp10 = tmp0 + tmp1;
tmp11 = tmp0 - tmp1;
tmp12 = tmp0 + tmp2;
tmp13 = tmp0 - tmp2;
z1 = (INT32) wsptr[2];
z2 = (INT32) wsptr[6];
z3 = z1 - z2;
z4 = MULTIPLY(z3, FIX(0.275899379)); /* c14[16] = c7[8] */
z3 = MULTIPLY(z3, FIX(1.387039845)); /* c2[16] = c1[8] */
tmp0 = z3 + MULTIPLY(z2, FIX_2_562915447); /* (c6+c2)[16] = (c3+c1)[8] */
tmp1 = z4 + MULTIPLY(z1, FIX_0_899976223); /* (c6-c14)[16] = (c3-c7)[8] */
tmp2 = z3 - MULTIPLY(z1, FIX(0.601344887)); /* (c2-c10)[16] = (c1-c5)[8] */
tmp3 = z4 - MULTIPLY(z2, FIX(0.509795579)); /* (c10-c14)[16] = (c5-c7)[8] */
tmp20 = tmp10 + tmp0;
tmp27 = tmp10 - tmp0;
tmp21 = tmp12 + tmp1;
tmp26 = tmp12 - tmp1;
tmp22 = tmp13 + tmp2;
tmp25 = tmp13 - tmp2;
tmp23 = tmp11 + tmp3;
tmp24 = tmp11 - tmp3;
/* Odd part */
z1 = (INT32) wsptr[1];
z2 = (INT32) wsptr[3];
z3 = (INT32) wsptr[5];
z4 = (INT32) wsptr[7];
tmp11 = z1 + z3;
tmp1 = MULTIPLY(z1 + z2, FIX(1.353318001)); /* c3 */
tmp2 = MULTIPLY(tmp11, FIX(1.247225013)); /* c5 */
tmp3 = MULTIPLY(z1 + z4, FIX(1.093201867)); /* c7 */
tmp10 = MULTIPLY(z1 - z4, FIX(0.897167586)); /* c9 */
tmp11 = MULTIPLY(tmp11, FIX(0.666655658)); /* c11 */
tmp12 = MULTIPLY(z1 - z2, FIX(0.410524528)); /* c13 */
tmp0 = tmp1 + tmp2 + tmp3 -
MULTIPLY(z1, FIX(2.286341144)); /* c7+c5+c3-c1 */
tmp13 = tmp10 + tmp11 + tmp12 -
MULTIPLY(z1, FIX(1.835730603)); /* c9+c11+c13-c15 */
z1 = MULTIPLY(z2 + z3, FIX(0.138617169)); /* c15 */
tmp1 += z1 + MULTIPLY(z2, FIX(0.071888074)); /* c9+c11-c3-c15 */
tmp2 += z1 - MULTIPLY(z3, FIX(1.125726048)); /* c5+c7+c15-c3 */
z1 = MULTIPLY(z3 - z2, FIX(1.407403738)); /* c1 */
tmp11 += z1 - MULTIPLY(z3, FIX(0.766367282)); /* c1+c11-c9-c13 */
tmp12 += z1 + MULTIPLY(z2, FIX(1.971951411)); /* c1+c5+c13-c7 */
z2 += z4;
z1 = MULTIPLY(z2, - FIX(0.666655658)); /* -c11 */
tmp1 += z1;
tmp3 += z1 + MULTIPLY(z4, FIX(1.065388962)); /* c3+c11+c15-c7 */
z2 = MULTIPLY(z2, - FIX(1.247225013)); /* -c5 */
tmp10 += z2 + MULTIPLY(z4, FIX(3.141271809)); /* c1+c5+c9-c13 */
tmp12 += z2;
z2 = MULTIPLY(z3 + z4, - FIX(1.353318001)); /* -c3 */
tmp2 += z2;
tmp3 += z2;
z2 = MULTIPLY(z4 - z3, FIX(0.410524528)); /* c13 */
tmp10 += z2;
tmp11 += z2;
/* Final output stage */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp20 + tmp0,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[15] = range_limit[(int) RIGHT_SHIFT(tmp20 - tmp0,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp21 + tmp1,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[14] = range_limit[(int) RIGHT_SHIFT(tmp21 - tmp1,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp22 + tmp2,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[13] = range_limit[(int) RIGHT_SHIFT(tmp22 - tmp2,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp23 + tmp3,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[12] = range_limit[(int) RIGHT_SHIFT(tmp23 - tmp3,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp24 + tmp10,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[11] = range_limit[(int) RIGHT_SHIFT(tmp24 - tmp10,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp25 + tmp11,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[10] = range_limit[(int) RIGHT_SHIFT(tmp25 - tmp11,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp26 + tmp12,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[9] = range_limit[(int) RIGHT_SHIFT(tmp26 - tmp12,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp27 + tmp13,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[8] = range_limit[(int) RIGHT_SHIFT(tmp27 - tmp13,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
wsptr += 8; /* advance pointer to next row */
}
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a 14x7 output block.
*
* 7-point IDCT in pass 1 (columns), 14-point in pass 2 (rows).
*/
void
jpeg_idct_14x7 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp10, tmp11, tmp12, tmp13, tmp14, tmp15, tmp16;
INT32 tmp20, tmp21, tmp22, tmp23, tmp24, tmp25, tmp26;
INT32 z1, z2, z3, z4;
JCOEFPTR inptr;
ISLOW_MULT_TYPE * quantptr;
int * wsptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
int workspace[8*7]; /* buffers data between passes */
SHIFT_TEMPS
/* Pass 1: process columns from input, store into work array.
* 7-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/14).
*/
inptr = coef_block;
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
wsptr = workspace;
for (ctr = 0; ctr < 8; ctr++, inptr++, quantptr++, wsptr++) {
/* Even part */
tmp23 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
tmp23 <<= CONST_BITS;
/* Add fudge factor here for final descale. */
tmp23 += ONE << (CONST_BITS-PASS1_BITS-1);
z1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
z2 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
z3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
tmp20 = MULTIPLY(z2 - z3, FIX(0.881747734)); /* c4 */
tmp22 = MULTIPLY(z1 - z2, FIX(0.314692123)); /* c6 */
tmp21 = tmp20 + tmp22 + tmp23 - MULTIPLY(z2, FIX(1.841218003)); /* c2+c4-c6 */
tmp10 = z1 + z3;
z2 -= tmp10;
tmp10 = MULTIPLY(tmp10, FIX(1.274162392)) + tmp23; /* c2 */
tmp20 += tmp10 - MULTIPLY(z3, FIX(0.077722536)); /* c2-c4-c6 */
tmp22 += tmp10 - MULTIPLY(z1, FIX(2.470602249)); /* c2+c4+c6 */
tmp23 += MULTIPLY(z2, FIX(1.414213562)); /* c0 */
/* Odd part */
z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
tmp11 = MULTIPLY(z1 + z2, FIX(0.935414347)); /* (c3+c1-c5)/2 */
tmp12 = MULTIPLY(z1 - z2, FIX(0.170262339)); /* (c3+c5-c1)/2 */
tmp10 = tmp11 - tmp12;
tmp11 += tmp12;
tmp12 = MULTIPLY(z2 + z3, - FIX(1.378756276)); /* -c1 */
tmp11 += tmp12;
z2 = MULTIPLY(z1 + z3, FIX(0.613604268)); /* c5 */
tmp10 += z2;
tmp12 += z2 + MULTIPLY(z3, FIX(1.870828693)); /* c3+c1-c5 */
/* Final output stage */
wsptr[8*0] = (int) RIGHT_SHIFT(tmp20 + tmp10, CONST_BITS-PASS1_BITS);
wsptr[8*6] = (int) RIGHT_SHIFT(tmp20 - tmp10, CONST_BITS-PASS1_BITS);
wsptr[8*1] = (int) RIGHT_SHIFT(tmp21 + tmp11, CONST_BITS-PASS1_BITS);
wsptr[8*5] = (int) RIGHT_SHIFT(tmp21 - tmp11, CONST_BITS-PASS1_BITS);
wsptr[8*2] = (int) RIGHT_SHIFT(tmp22 + tmp12, CONST_BITS-PASS1_BITS);
wsptr[8*4] = (int) RIGHT_SHIFT(tmp22 - tmp12, CONST_BITS-PASS1_BITS);
wsptr[8*3] = (int) RIGHT_SHIFT(tmp23, CONST_BITS-PASS1_BITS);
}
/* Pass 2: process 7 rows from work array, store into output array.
* 14-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/28).
*/
wsptr = workspace;
for (ctr = 0; ctr < 7; ctr++) {
outptr = output_buf[ctr] + output_col;
/* Even part */
/* Add fudge factor here for final descale. */
z1 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
z1 <<= CONST_BITS;
z4 = (INT32) wsptr[4];
z2 = MULTIPLY(z4, FIX(1.274162392)); /* c4 */
z3 = MULTIPLY(z4, FIX(0.314692123)); /* c12 */
z4 = MULTIPLY(z4, FIX(0.881747734)); /* c8 */
tmp10 = z1 + z2;
tmp11 = z1 + z3;
tmp12 = z1 - z4;
tmp23 = z1 - ((z2 + z3 - z4) << 1); /* c0 = (c4+c12-c8)*2 */
z1 = (INT32) wsptr[2];
z2 = (INT32) wsptr[6];
z3 = MULTIPLY(z1 + z2, FIX(1.105676686)); /* c6 */
tmp13 = z3 + MULTIPLY(z1, FIX(0.273079590)); /* c2-c6 */
tmp14 = z3 - MULTIPLY(z2, FIX(1.719280954)); /* c6+c10 */
tmp15 = MULTIPLY(z1, FIX(0.613604268)) - /* c10 */
MULTIPLY(z2, FIX(1.378756276)); /* c2 */
tmp20 = tmp10 + tmp13;
tmp26 = tmp10 - tmp13;
tmp21 = tmp11 + tmp14;
tmp25 = tmp11 - tmp14;
tmp22 = tmp12 + tmp15;
tmp24 = tmp12 - tmp15;
/* Odd part */
z1 = (INT32) wsptr[1];
z2 = (INT32) wsptr[3];
z3 = (INT32) wsptr[5];
z4 = (INT32) wsptr[7];
z4 <<= CONST_BITS;
tmp14 = z1 + z3;
tmp11 = MULTIPLY(z1 + z2, FIX(1.334852607)); /* c3 */
tmp12 = MULTIPLY(tmp14, FIX(1.197448846)); /* c5 */
tmp10 = tmp11 + tmp12 + z4 - MULTIPLY(z1, FIX(1.126980169)); /* c3+c5-c1 */
tmp14 = MULTIPLY(tmp14, FIX(0.752406978)); /* c9 */
tmp16 = tmp14 - MULTIPLY(z1, FIX(1.061150426)); /* c9+c11-c13 */
z1 -= z2;
tmp15 = MULTIPLY(z1, FIX(0.467085129)) - z4; /* c11 */
tmp16 += tmp15;
tmp13 = MULTIPLY(z2 + z3, - FIX(0.158341681)) - z4; /* -c13 */
tmp11 += tmp13 - MULTIPLY(z2, FIX(0.424103948)); /* c3-c9-c13 */
tmp12 += tmp13 - MULTIPLY(z3, FIX(2.373959773)); /* c3+c5-c13 */
tmp13 = MULTIPLY(z3 - z2, FIX(1.405321284)); /* c1 */
tmp14 += tmp13 + z4 - MULTIPLY(z3, FIX(1.6906431334)); /* c1+c9-c11 */
tmp15 += tmp13 + MULTIPLY(z2, FIX(0.674957567)); /* c1+c11-c5 */
tmp13 = ((z1 - z3) << CONST_BITS) + z4;
/* Final output stage */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp20 + tmp10,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[13] = range_limit[(int) RIGHT_SHIFT(tmp20 - tmp10,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp21 + tmp11,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[12] = range_limit[(int) RIGHT_SHIFT(tmp21 - tmp11,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp22 + tmp12,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[11] = range_limit[(int) RIGHT_SHIFT(tmp22 - tmp12,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp23 + tmp13,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[10] = range_limit[(int) RIGHT_SHIFT(tmp23 - tmp13,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp24 + tmp14,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[9] = range_limit[(int) RIGHT_SHIFT(tmp24 - tmp14,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp25 + tmp15,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[8] = range_limit[(int) RIGHT_SHIFT(tmp25 - tmp15,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp26 + tmp16,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp26 - tmp16,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
wsptr += 8; /* advance pointer to next row */
}
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a 12x6 output block.
*
* 6-point IDCT in pass 1 (columns), 12-point in pass 2 (rows).
*/
void
jpeg_idct_12x6 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp10, tmp11, tmp12, tmp13, tmp14, tmp15;
INT32 tmp20, tmp21, tmp22, tmp23, tmp24, tmp25;
INT32 z1, z2, z3, z4;
JCOEFPTR inptr;
ISLOW_MULT_TYPE * quantptr;
int * wsptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
int workspace[8*6]; /* buffers data between passes */
SHIFT_TEMPS
/* Pass 1: process columns from input, store into work array.
* 6-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/12).
*/
inptr = coef_block;
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
wsptr = workspace;
for (ctr = 0; ctr < 8; ctr++, inptr++, quantptr++, wsptr++) {
/* Even part */
tmp10 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
tmp10 <<= CONST_BITS;
/* Add fudge factor here for final descale. */
tmp10 += ONE << (CONST_BITS-PASS1_BITS-1);
tmp12 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
tmp20 = MULTIPLY(tmp12, FIX(0.707106781)); /* c4 */
tmp11 = tmp10 + tmp20;
tmp21 = RIGHT_SHIFT(tmp10 - tmp20 - tmp20, CONST_BITS-PASS1_BITS);
tmp20 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
tmp10 = MULTIPLY(tmp20, FIX(1.224744871)); /* c2 */
tmp20 = tmp11 + tmp10;
tmp22 = tmp11 - tmp10;
/* Odd part */
z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
tmp11 = MULTIPLY(z1 + z3, FIX(0.366025404)); /* c5 */
tmp10 = tmp11 + ((z1 + z2) << CONST_BITS);
tmp12 = tmp11 + ((z3 - z2) << CONST_BITS);
tmp11 = (z1 - z2 - z3) << PASS1_BITS;
/* Final output stage */
wsptr[8*0] = (int) RIGHT_SHIFT(tmp20 + tmp10, CONST_BITS-PASS1_BITS);
wsptr[8*5] = (int) RIGHT_SHIFT(tmp20 - tmp10, CONST_BITS-PASS1_BITS);
wsptr[8*1] = (int) (tmp21 + tmp11);
wsptr[8*4] = (int) (tmp21 - tmp11);
wsptr[8*2] = (int) RIGHT_SHIFT(tmp22 + tmp12, CONST_BITS-PASS1_BITS);
wsptr[8*3] = (int) RIGHT_SHIFT(tmp22 - tmp12, CONST_BITS-PASS1_BITS);
}
/* Pass 2: process 6 rows from work array, store into output array.
* 12-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/24).
*/
wsptr = workspace;
for (ctr = 0; ctr < 6; ctr++) {
outptr = output_buf[ctr] + output_col;
/* Even part */
/* Add fudge factor here for final descale. */
z3 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
z3 <<= CONST_BITS;
z4 = (INT32) wsptr[4];
z4 = MULTIPLY(z4, FIX(1.224744871)); /* c4 */
tmp10 = z3 + z4;
tmp11 = z3 - z4;
z1 = (INT32) wsptr[2];
z4 = MULTIPLY(z1, FIX(1.366025404)); /* c2 */
z1 <<= CONST_BITS;
z2 = (INT32) wsptr[6];
z2 <<= CONST_BITS;
tmp12 = z1 - z2;
tmp21 = z3 + tmp12;
tmp24 = z3 - tmp12;
tmp12 = z4 + z2;
tmp20 = tmp10 + tmp12;
tmp25 = tmp10 - tmp12;
tmp12 = z4 - z1 - z2;
tmp22 = tmp11 + tmp12;
tmp23 = tmp11 - tmp12;
/* Odd part */
z1 = (INT32) wsptr[1];
z2 = (INT32) wsptr[3];
z3 = (INT32) wsptr[5];
z4 = (INT32) wsptr[7];
tmp11 = MULTIPLY(z2, FIX(1.306562965)); /* c3 */
tmp14 = MULTIPLY(z2, - FIX_0_541196100); /* -c9 */
tmp10 = z1 + z3;
tmp15 = MULTIPLY(tmp10 + z4, FIX(0.860918669)); /* c7 */
tmp12 = tmp15 + MULTIPLY(tmp10, FIX(0.261052384)); /* c5-c7 */
tmp10 = tmp12 + tmp11 + MULTIPLY(z1, FIX(0.280143716)); /* c1-c5 */
tmp13 = MULTIPLY(z3 + z4, - FIX(1.045510580)); /* -(c7+c11) */
tmp12 += tmp13 + tmp14 - MULTIPLY(z3, FIX(1.478575242)); /* c1+c5-c7-c11 */
tmp13 += tmp15 - tmp11 + MULTIPLY(z4, FIX(1.586706681)); /* c1+c11 */
tmp15 += tmp14 - MULTIPLY(z1, FIX(0.676326758)) - /* c7-c11 */
MULTIPLY(z4, FIX(1.982889723)); /* c5+c7 */
z1 -= z4;
z2 -= z3;
z3 = MULTIPLY(z1 + z2, FIX_0_541196100); /* c9 */
tmp11 = z3 + MULTIPLY(z1, FIX_0_765366865); /* c3-c9 */
tmp14 = z3 - MULTIPLY(z2, FIX_1_847759065); /* c3+c9 */
/* Final output stage */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp20 + tmp10,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[11] = range_limit[(int) RIGHT_SHIFT(tmp20 - tmp10,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp21 + tmp11,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[10] = range_limit[(int) RIGHT_SHIFT(tmp21 - tmp11,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp22 + tmp12,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[9] = range_limit[(int) RIGHT_SHIFT(tmp22 - tmp12,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp23 + tmp13,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[8] = range_limit[(int) RIGHT_SHIFT(tmp23 - tmp13,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp24 + tmp14,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp24 - tmp14,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp25 + tmp15,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp25 - tmp15,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
wsptr += 8; /* advance pointer to next row */
}
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a 10x5 output block.
*
* 5-point IDCT in pass 1 (columns), 10-point in pass 2 (rows).
*/
void
jpeg_idct_10x5 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp10, tmp11, tmp12, tmp13, tmp14;
INT32 tmp20, tmp21, tmp22, tmp23, tmp24;
INT32 z1, z2, z3, z4;
JCOEFPTR inptr;
ISLOW_MULT_TYPE * quantptr;
int * wsptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
int workspace[8*5]; /* buffers data between passes */
SHIFT_TEMPS
/* Pass 1: process columns from input, store into work array.
* 5-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/10).
*/
inptr = coef_block;
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
wsptr = workspace;
for (ctr = 0; ctr < 8; ctr++, inptr++, quantptr++, wsptr++) {
/* Even part */
tmp12 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
tmp12 <<= CONST_BITS;
/* Add fudge factor here for final descale. */
tmp12 += ONE << (CONST_BITS-PASS1_BITS-1);
tmp13 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
tmp14 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
z1 = MULTIPLY(tmp13 + tmp14, FIX(0.790569415)); /* (c2+c4)/2 */
z2 = MULTIPLY(tmp13 - tmp14, FIX(0.353553391)); /* (c2-c4)/2 */
z3 = tmp12 + z2;
tmp10 = z3 + z1;
tmp11 = z3 - z1;
tmp12 -= z2 << 2;
/* Odd part */
z2 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
z3 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
z1 = MULTIPLY(z2 + z3, FIX(0.831253876)); /* c3 */
tmp13 = z1 + MULTIPLY(z2, FIX(0.513743148)); /* c1-c3 */
tmp14 = z1 - MULTIPLY(z3, FIX(2.176250899)); /* c1+c3 */
/* Final output stage */
wsptr[8*0] = (int) RIGHT_SHIFT(tmp10 + tmp13, CONST_BITS-PASS1_BITS);
wsptr[8*4] = (int) RIGHT_SHIFT(tmp10 - tmp13, CONST_BITS-PASS1_BITS);
wsptr[8*1] = (int) RIGHT_SHIFT(tmp11 + tmp14, CONST_BITS-PASS1_BITS);
wsptr[8*3] = (int) RIGHT_SHIFT(tmp11 - tmp14, CONST_BITS-PASS1_BITS);
wsptr[8*2] = (int) RIGHT_SHIFT(tmp12, CONST_BITS-PASS1_BITS);
}
/* Pass 2: process 5 rows from work array, store into output array.
* 10-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/20).
*/
wsptr = workspace;
for (ctr = 0; ctr < 5; ctr++) {
outptr = output_buf[ctr] + output_col;
/* Even part */
/* Add fudge factor here for final descale. */
z3 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
z3 <<= CONST_BITS;
z4 = (INT32) wsptr[4];
z1 = MULTIPLY(z4, FIX(1.144122806)); /* c4 */
z2 = MULTIPLY(z4, FIX(0.437016024)); /* c8 */
tmp10 = z3 + z1;
tmp11 = z3 - z2;
tmp22 = z3 - ((z1 - z2) << 1); /* c0 = (c4-c8)*2 */
z2 = (INT32) wsptr[2];
z3 = (INT32) wsptr[6];
z1 = MULTIPLY(z2 + z3, FIX(0.831253876)); /* c6 */
tmp12 = z1 + MULTIPLY(z2, FIX(0.513743148)); /* c2-c6 */
tmp13 = z1 - MULTIPLY(z3, FIX(2.176250899)); /* c2+c6 */
tmp20 = tmp10 + tmp12;
tmp24 = tmp10 - tmp12;
tmp21 = tmp11 + tmp13;
tmp23 = tmp11 - tmp13;
/* Odd part */
z1 = (INT32) wsptr[1];
z2 = (INT32) wsptr[3];
z3 = (INT32) wsptr[5];
z3 <<= CONST_BITS;
z4 = (INT32) wsptr[7];
tmp11 = z2 + z4;
tmp13 = z2 - z4;
tmp12 = MULTIPLY(tmp13, FIX(0.309016994)); /* (c3-c7)/2 */
z2 = MULTIPLY(tmp11, FIX(0.951056516)); /* (c3+c7)/2 */
z4 = z3 + tmp12;
tmp10 = MULTIPLY(z1, FIX(1.396802247)) + z2 + z4; /* c1 */
tmp14 = MULTIPLY(z1, FIX(0.221231742)) - z2 + z4; /* c9 */
z2 = MULTIPLY(tmp11, FIX(0.587785252)); /* (c1-c9)/2 */
z4 = z3 - tmp12 - (tmp13 << (CONST_BITS - 1));
tmp12 = ((z1 - tmp13) << CONST_BITS) - z3;
tmp11 = MULTIPLY(z1, FIX(1.260073511)) - z2 - z4; /* c3 */
tmp13 = MULTIPLY(z1, FIX(0.642039522)) - z2 + z4; /* c7 */
/* Final output stage */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp20 + tmp10,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[9] = range_limit[(int) RIGHT_SHIFT(tmp20 - tmp10,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp21 + tmp11,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[8] = range_limit[(int) RIGHT_SHIFT(tmp21 - tmp11,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp22 + tmp12,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp22 - tmp12,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp23 + tmp13,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp23 - tmp13,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp24 + tmp14,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp24 - tmp14,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
wsptr += 8; /* advance pointer to next row */
}
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a 8x4 output block.
*
* 4-point IDCT in pass 1 (columns), 8-point in pass 2 (rows).
*/
void
jpeg_idct_8x4 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp0, tmp1, tmp2, tmp3;
INT32 tmp10, tmp11, tmp12, tmp13;
INT32 z1, z2, z3;
JCOEFPTR inptr;
ISLOW_MULT_TYPE * quantptr;
int * wsptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
int workspace[8*4]; /* buffers data between passes */
SHIFT_TEMPS
/* Pass 1: process columns from input, store into work array.
* 4-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/16).
*/
inptr = coef_block;
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
wsptr = workspace;
for (ctr = 0; ctr < 8; ctr++, inptr++, quantptr++, wsptr++) {
/* Even part */
tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
tmp2 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
tmp10 = (tmp0 + tmp2) << PASS1_BITS;
tmp12 = (tmp0 - tmp2) << PASS1_BITS;
/* Odd part */
/* Same rotation as in the even part of the 8x8 LL&M IDCT */
z2 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
z3 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
z1 = MULTIPLY(z2 + z3, FIX_0_541196100); /* c6 */
/* Add fudge factor here for final descale. */
z1 += ONE << (CONST_BITS-PASS1_BITS-1);
tmp0 = RIGHT_SHIFT(z1 + MULTIPLY(z2, FIX_0_765366865), /* c2-c6 */
CONST_BITS-PASS1_BITS);
tmp2 = RIGHT_SHIFT(z1 - MULTIPLY(z3, FIX_1_847759065), /* c2+c6 */
CONST_BITS-PASS1_BITS);
/* Final output stage */
wsptr[8*0] = (int) (tmp10 + tmp0);
wsptr[8*3] = (int) (tmp10 - tmp0);
wsptr[8*1] = (int) (tmp12 + tmp2);
wsptr[8*2] = (int) (tmp12 - tmp2);
}
/* Pass 2: process rows from work array, store into output array. */
/* Note that we must descale the results by a factor of 8 == 2**3, */
/* and also undo the PASS1_BITS scaling. */
wsptr = workspace;
for (ctr = 0; ctr < 4; ctr++) {
outptr = output_buf[ctr] + output_col;
/* Even part: reverse the even part of the forward DCT. */
/* The rotator is sqrt(2)*c(-6). */
z2 = (INT32) wsptr[2];
z3 = (INT32) wsptr[6];
z1 = MULTIPLY(z2 + z3, FIX_0_541196100);
tmp2 = z1 + MULTIPLY(z2, FIX_0_765366865);
tmp3 = z1 - MULTIPLY(z3, FIX_1_847759065);
/* Add fudge factor here for final descale. */
z2 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
z3 = (INT32) wsptr[4];
tmp0 = (z2 + z3) << CONST_BITS;
tmp1 = (z2 - z3) << CONST_BITS;
tmp10 = tmp0 + tmp2;
tmp13 = tmp0 - tmp2;
tmp11 = tmp1 + tmp3;
tmp12 = tmp1 - tmp3;
/* Odd part per figure 8; the matrix is unitary and hence its
* transpose is its inverse. i0..i3 are y7,y5,y3,y1 respectively.
*/
tmp0 = (INT32) wsptr[7];
tmp1 = (INT32) wsptr[5];
tmp2 = (INT32) wsptr[3];
tmp3 = (INT32) wsptr[1];
z2 = tmp0 + tmp2;
z3 = tmp1 + tmp3;
z1 = MULTIPLY(z2 + z3, FIX_1_175875602); /* sqrt(2) * c3 */
z2 = MULTIPLY(z2, - FIX_1_961570560); /* sqrt(2) * (-c3-c5) */
z3 = MULTIPLY(z3, - FIX_0_390180644); /* sqrt(2) * (c5-c3) */
z2 += z1;
z3 += z1;
z1 = MULTIPLY(tmp0 + tmp3, - FIX_0_899976223); /* sqrt(2) * (c7-c3) */
tmp0 = MULTIPLY(tmp0, FIX_0_298631336); /* sqrt(2) * (-c1+c3+c5-c7) */
tmp3 = MULTIPLY(tmp3, FIX_1_501321110); /* sqrt(2) * ( c1+c3-c5-c7) */
tmp0 += z1 + z2;
tmp3 += z1 + z3;
z1 = MULTIPLY(tmp1 + tmp2, - FIX_2_562915447); /* sqrt(2) * (-c1-c3) */
tmp1 = MULTIPLY(tmp1, FIX_2_053119869); /* sqrt(2) * ( c1+c3-c5+c7) */
tmp2 = MULTIPLY(tmp2, FIX_3_072711026); /* sqrt(2) * ( c1+c3+c5-c7) */
tmp1 += z1 + z3;
tmp2 += z1 + z2;
/* Final output stage: inputs are tmp10..tmp13, tmp0..tmp3 */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp3,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp3,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp11 + tmp2,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp11 - tmp2,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp12 + tmp1,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp12 - tmp1,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp13 + tmp0,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp13 - tmp0,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
wsptr += DCTSIZE; /* advance pointer to next row */
}
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a reduced-size 6x3 output block.
*
* 3-point IDCT in pass 1 (columns), 6-point in pass 2 (rows).
*/
void
jpeg_idct_6x3 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp0, tmp1, tmp2, tmp10, tmp11, tmp12;
INT32 z1, z2, z3;
JCOEFPTR inptr;
ISLOW_MULT_TYPE * quantptr;
int * wsptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
int workspace[6*3]; /* buffers data between passes */
SHIFT_TEMPS
/* Pass 1: process columns from input, store into work array.
* 3-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/6).
*/
inptr = coef_block;
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
wsptr = workspace;
for (ctr = 0; ctr < 6; ctr++, inptr++, quantptr++, wsptr++) {
/* Even part */
tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
tmp0 <<= CONST_BITS;
/* Add fudge factor here for final descale. */
tmp0 += ONE << (CONST_BITS-PASS1_BITS-1);
tmp2 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
tmp12 = MULTIPLY(tmp2, FIX(0.707106781)); /* c2 */
tmp10 = tmp0 + tmp12;
tmp2 = tmp0 - tmp12 - tmp12;
/* Odd part */
tmp12 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
tmp0 = MULTIPLY(tmp12, FIX(1.224744871)); /* c1 */
/* Final output stage */
wsptr[6*0] = (int) RIGHT_SHIFT(tmp10 + tmp0, CONST_BITS-PASS1_BITS);
wsptr[6*2] = (int) RIGHT_SHIFT(tmp10 - tmp0, CONST_BITS-PASS1_BITS);
wsptr[6*1] = (int) RIGHT_SHIFT(tmp2, CONST_BITS-PASS1_BITS);
}
/* Pass 2: process 3 rows from work array, store into output array.
* 6-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/12).
*/
wsptr = workspace;
for (ctr = 0; ctr < 3; ctr++) {
outptr = output_buf[ctr] + output_col;
/* Even part */
/* Add fudge factor here for final descale. */
tmp0 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
tmp0 <<= CONST_BITS;
tmp2 = (INT32) wsptr[4];
tmp10 = MULTIPLY(tmp2, FIX(0.707106781)); /* c4 */
tmp1 = tmp0 + tmp10;
tmp11 = tmp0 - tmp10 - tmp10;
tmp10 = (INT32) wsptr[2];
tmp0 = MULTIPLY(tmp10, FIX(1.224744871)); /* c2 */
tmp10 = tmp1 + tmp0;
tmp12 = tmp1 - tmp0;
/* Odd part */
z1 = (INT32) wsptr[1];
z2 = (INT32) wsptr[3];
z3 = (INT32) wsptr[5];
tmp1 = MULTIPLY(z1 + z3, FIX(0.366025404)); /* c5 */
tmp0 = tmp1 + ((z1 + z2) << CONST_BITS);
tmp2 = tmp1 + ((z3 - z2) << CONST_BITS);
tmp1 = (z1 - z2 - z3) << CONST_BITS;
/* Final output stage */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp0,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp0,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp11 + tmp1,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp11 - tmp1,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp12 + tmp2,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp12 - tmp2,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
wsptr += 6; /* advance pointer to next row */
}
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a 4x2 output block.
*
* 2-point IDCT in pass 1 (columns), 4-point in pass 2 (rows).
*/
void
jpeg_idct_4x2 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp0, tmp2, tmp10, tmp12;
INT32 z1, z2, z3;
JCOEFPTR inptr;
ISLOW_MULT_TYPE * quantptr;
INT32 * wsptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
INT32 workspace[4*2]; /* buffers data between passes */
SHIFT_TEMPS
/* Pass 1: process columns from input, store into work array. */
inptr = coef_block;
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
wsptr = workspace;
for (ctr = 0; ctr < 4; ctr++, inptr++, quantptr++, wsptr++) {
/* Even part */
tmp10 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
/* Odd part */
tmp0 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
/* Final output stage */
wsptr[4*0] = tmp10 + tmp0;
wsptr[4*1] = tmp10 - tmp0;
}
/* Pass 2: process 2 rows from work array, store into output array.
* 4-point IDCT kernel,
* cK represents sqrt(2) * cos(K*pi/16) [refers to 8-point IDCT].
*/
wsptr = workspace;
for (ctr = 0; ctr < 2; ctr++) {
outptr = output_buf[ctr] + output_col;
/* Even part */
/* Add fudge factor here for final descale. */
tmp0 = wsptr[0] + (ONE << 2);
tmp2 = wsptr[2];
tmp10 = (tmp0 + tmp2) << CONST_BITS;
tmp12 = (tmp0 - tmp2) << CONST_BITS;
/* Odd part */
/* Same rotation as in the even part of the 8x8 LL&M IDCT */
z2 = wsptr[1];
z3 = wsptr[3];
z1 = MULTIPLY(z2 + z3, FIX_0_541196100); /* c6 */
tmp0 = z1 + MULTIPLY(z2, FIX_0_765366865); /* c2-c6 */
tmp2 = z1 - MULTIPLY(z3, FIX_1_847759065); /* c2+c6 */
/* Final output stage */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp0,
CONST_BITS+3)
& RANGE_MASK];
outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp0,
CONST_BITS+3)
& RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp12 + tmp2,
CONST_BITS+3)
& RANGE_MASK];
outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp12 - tmp2,
CONST_BITS+3)
& RANGE_MASK];
wsptr += 4; /* advance pointer to next row */
}
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a 2x1 output block.
*
* 1-point IDCT in pass 1 (columns), 2-point in pass 2 (rows).
*/
void
jpeg_idct_2x1 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp0, tmp10;
ISLOW_MULT_TYPE * quantptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
SHIFT_TEMPS
/* Pass 1: empty. */
/* Pass 2: process 1 row from input, store into output array. */
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
outptr = output_buf[0] + output_col;
/* Even part */
tmp10 = DEQUANTIZE(coef_block[0], quantptr[0]);
/* Add fudge factor here for final descale. */
tmp10 += ONE << 2;
/* Odd part */
tmp0 = DEQUANTIZE(coef_block[1], quantptr[1]);
/* Final output stage */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp0, 3) & RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp0, 3) & RANGE_MASK];
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a 8x16 output block.
*
* 16-point IDCT in pass 1 (columns), 8-point in pass 2 (rows).
*/
void
jpeg_idct_8x16 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp0, tmp1, tmp2, tmp3, tmp10, tmp11, tmp12, tmp13;
INT32 tmp20, tmp21, tmp22, tmp23, tmp24, tmp25, tmp26, tmp27;
INT32 z1, z2, z3, z4;
JCOEFPTR inptr;
ISLOW_MULT_TYPE * quantptr;
int * wsptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
int workspace[8*16]; /* buffers data between passes */
SHIFT_TEMPS
/* Pass 1: process columns from input, store into work array.
* 16-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/32).
*/
inptr = coef_block;
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
wsptr = workspace;
for (ctr = 0; ctr < 8; ctr++, inptr++, quantptr++, wsptr++) {
/* Even part */
tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
tmp0 <<= CONST_BITS;
/* Add fudge factor here for final descale. */
tmp0 += ONE << (CONST_BITS-PASS1_BITS-1);
z1 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
tmp1 = MULTIPLY(z1, FIX(1.306562965)); /* c4[16] = c2[8] */
tmp2 = MULTIPLY(z1, FIX_0_541196100); /* c12[16] = c6[8] */
tmp10 = tmp0 + tmp1;
tmp11 = tmp0 - tmp1;
tmp12 = tmp0 + tmp2;
tmp13 = tmp0 - tmp2;
z1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
z2 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
z3 = z1 - z2;
z4 = MULTIPLY(z3, FIX(0.275899379)); /* c14[16] = c7[8] */
z3 = MULTIPLY(z3, FIX(1.387039845)); /* c2[16] = c1[8] */
tmp0 = z3 + MULTIPLY(z2, FIX_2_562915447); /* (c6+c2)[16] = (c3+c1)[8] */
tmp1 = z4 + MULTIPLY(z1, FIX_0_899976223); /* (c6-c14)[16] = (c3-c7)[8] */
tmp2 = z3 - MULTIPLY(z1, FIX(0.601344887)); /* (c2-c10)[16] = (c1-c5)[8] */
tmp3 = z4 - MULTIPLY(z2, FIX(0.509795579)); /* (c10-c14)[16] = (c5-c7)[8] */
tmp20 = tmp10 + tmp0;
tmp27 = tmp10 - tmp0;
tmp21 = tmp12 + tmp1;
tmp26 = tmp12 - tmp1;
tmp22 = tmp13 + tmp2;
tmp25 = tmp13 - tmp2;
tmp23 = tmp11 + tmp3;
tmp24 = tmp11 - tmp3;
/* Odd part */
z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
z4 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
tmp11 = z1 + z3;
tmp1 = MULTIPLY(z1 + z2, FIX(1.353318001)); /* c3 */
tmp2 = MULTIPLY(tmp11, FIX(1.247225013)); /* c5 */
tmp3 = MULTIPLY(z1 + z4, FIX(1.093201867)); /* c7 */
tmp10 = MULTIPLY(z1 - z4, FIX(0.897167586)); /* c9 */
tmp11 = MULTIPLY(tmp11, FIX(0.666655658)); /* c11 */
tmp12 = MULTIPLY(z1 - z2, FIX(0.410524528)); /* c13 */
tmp0 = tmp1 + tmp2 + tmp3 -
MULTIPLY(z1, FIX(2.286341144)); /* c7+c5+c3-c1 */
tmp13 = tmp10 + tmp11 + tmp12 -
MULTIPLY(z1, FIX(1.835730603)); /* c9+c11+c13-c15 */
z1 = MULTIPLY(z2 + z3, FIX(0.138617169)); /* c15 */
tmp1 += z1 + MULTIPLY(z2, FIX(0.071888074)); /* c9+c11-c3-c15 */
tmp2 += z1 - MULTIPLY(z3, FIX(1.125726048)); /* c5+c7+c15-c3 */
z1 = MULTIPLY(z3 - z2, FIX(1.407403738)); /* c1 */
tmp11 += z1 - MULTIPLY(z3, FIX(0.766367282)); /* c1+c11-c9-c13 */
tmp12 += z1 + MULTIPLY(z2, FIX(1.971951411)); /* c1+c5+c13-c7 */
z2 += z4;
z1 = MULTIPLY(z2, - FIX(0.666655658)); /* -c11 */
tmp1 += z1;
tmp3 += z1 + MULTIPLY(z4, FIX(1.065388962)); /* c3+c11+c15-c7 */
z2 = MULTIPLY(z2, - FIX(1.247225013)); /* -c5 */
tmp10 += z2 + MULTIPLY(z4, FIX(3.141271809)); /* c1+c5+c9-c13 */
tmp12 += z2;
z2 = MULTIPLY(z3 + z4, - FIX(1.353318001)); /* -c3 */
tmp2 += z2;
tmp3 += z2;
z2 = MULTIPLY(z4 - z3, FIX(0.410524528)); /* c13 */
tmp10 += z2;
tmp11 += z2;
/* Final output stage */
wsptr[8*0] = (int) RIGHT_SHIFT(tmp20 + tmp0, CONST_BITS-PASS1_BITS);
wsptr[8*15] = (int) RIGHT_SHIFT(tmp20 - tmp0, CONST_BITS-PASS1_BITS);
wsptr[8*1] = (int) RIGHT_SHIFT(tmp21 + tmp1, CONST_BITS-PASS1_BITS);
wsptr[8*14] = (int) RIGHT_SHIFT(tmp21 - tmp1, CONST_BITS-PASS1_BITS);
wsptr[8*2] = (int) RIGHT_SHIFT(tmp22 + tmp2, CONST_BITS-PASS1_BITS);
wsptr[8*13] = (int) RIGHT_SHIFT(tmp22 - tmp2, CONST_BITS-PASS1_BITS);
wsptr[8*3] = (int) RIGHT_SHIFT(tmp23 + tmp3, CONST_BITS-PASS1_BITS);
wsptr[8*12] = (int) RIGHT_SHIFT(tmp23 - tmp3, CONST_BITS-PASS1_BITS);
wsptr[8*4] = (int) RIGHT_SHIFT(tmp24 + tmp10, CONST_BITS-PASS1_BITS);
wsptr[8*11] = (int) RIGHT_SHIFT(tmp24 - tmp10, CONST_BITS-PASS1_BITS);
wsptr[8*5] = (int) RIGHT_SHIFT(tmp25 + tmp11, CONST_BITS-PASS1_BITS);
wsptr[8*10] = (int) RIGHT_SHIFT(tmp25 - tmp11, CONST_BITS-PASS1_BITS);
wsptr[8*6] = (int) RIGHT_SHIFT(tmp26 + tmp12, CONST_BITS-PASS1_BITS);
wsptr[8*9] = (int) RIGHT_SHIFT(tmp26 - tmp12, CONST_BITS-PASS1_BITS);
wsptr[8*7] = (int) RIGHT_SHIFT(tmp27 + tmp13, CONST_BITS-PASS1_BITS);
wsptr[8*8] = (int) RIGHT_SHIFT(tmp27 - tmp13, CONST_BITS-PASS1_BITS);
}
/* Pass 2: process rows from work array, store into output array. */
/* Note that we must descale the results by a factor of 8 == 2**3, */
/* and also undo the PASS1_BITS scaling. */
wsptr = workspace;
for (ctr = 0; ctr < 16; ctr++) {
outptr = output_buf[ctr] + output_col;
/* Even part: reverse the even part of the forward DCT. */
/* The rotator is sqrt(2)*c(-6). */
z2 = (INT32) wsptr[2];
z3 = (INT32) wsptr[6];
z1 = MULTIPLY(z2 + z3, FIX_0_541196100);
tmp2 = z1 + MULTIPLY(z2, FIX_0_765366865);
tmp3 = z1 - MULTIPLY(z3, FIX_1_847759065);
/* Add fudge factor here for final descale. */
z2 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
z3 = (INT32) wsptr[4];
tmp0 = (z2 + z3) << CONST_BITS;
tmp1 = (z2 - z3) << CONST_BITS;
tmp10 = tmp0 + tmp2;
tmp13 = tmp0 - tmp2;
tmp11 = tmp1 + tmp3;
tmp12 = tmp1 - tmp3;
/* Odd part per figure 8; the matrix is unitary and hence its
* transpose is its inverse. i0..i3 are y7,y5,y3,y1 respectively.
*/
tmp0 = (INT32) wsptr[7];
tmp1 = (INT32) wsptr[5];
tmp2 = (INT32) wsptr[3];
tmp3 = (INT32) wsptr[1];
z2 = tmp0 + tmp2;
z3 = tmp1 + tmp3;
z1 = MULTIPLY(z2 + z3, FIX_1_175875602); /* sqrt(2) * c3 */
z2 = MULTIPLY(z2, - FIX_1_961570560); /* sqrt(2) * (-c3-c5) */
z3 = MULTIPLY(z3, - FIX_0_390180644); /* sqrt(2) * (c5-c3) */
z2 += z1;
z3 += z1;
z1 = MULTIPLY(tmp0 + tmp3, - FIX_0_899976223); /* sqrt(2) * (c7-c3) */
tmp0 = MULTIPLY(tmp0, FIX_0_298631336); /* sqrt(2) * (-c1+c3+c5-c7) */
tmp3 = MULTIPLY(tmp3, FIX_1_501321110); /* sqrt(2) * ( c1+c3-c5-c7) */
tmp0 += z1 + z2;
tmp3 += z1 + z3;
z1 = MULTIPLY(tmp1 + tmp2, - FIX_2_562915447); /* sqrt(2) * (-c1-c3) */
tmp1 = MULTIPLY(tmp1, FIX_2_053119869); /* sqrt(2) * ( c1+c3-c5+c7) */
tmp2 = MULTIPLY(tmp2, FIX_3_072711026); /* sqrt(2) * ( c1+c3+c5-c7) */
tmp1 += z1 + z3;
tmp2 += z1 + z2;
/* Final output stage: inputs are tmp10..tmp13, tmp0..tmp3 */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp3,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[7] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp3,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp11 + tmp2,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp11 - tmp2,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp12 + tmp1,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp12 - tmp1,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp13 + tmp0,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp13 - tmp0,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
wsptr += DCTSIZE; /* advance pointer to next row */
}
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a 7x14 output block.
*
* 14-point IDCT in pass 1 (columns), 7-point in pass 2 (rows).
*/
void
jpeg_idct_7x14 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp10, tmp11, tmp12, tmp13, tmp14, tmp15, tmp16;
INT32 tmp20, tmp21, tmp22, tmp23, tmp24, tmp25, tmp26;
INT32 z1, z2, z3, z4;
JCOEFPTR inptr;
ISLOW_MULT_TYPE * quantptr;
int * wsptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
int workspace[7*14]; /* buffers data between passes */
SHIFT_TEMPS
/* Pass 1: process columns from input, store into work array.
* 14-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/28).
*/
inptr = coef_block;
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
wsptr = workspace;
for (ctr = 0; ctr < 7; ctr++, inptr++, quantptr++, wsptr++) {
/* Even part */
z1 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
z1 <<= CONST_BITS;
/* Add fudge factor here for final descale. */
z1 += ONE << (CONST_BITS-PASS1_BITS-1);
z4 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
z2 = MULTIPLY(z4, FIX(1.274162392)); /* c4 */
z3 = MULTIPLY(z4, FIX(0.314692123)); /* c12 */
z4 = MULTIPLY(z4, FIX(0.881747734)); /* c8 */
tmp10 = z1 + z2;
tmp11 = z1 + z3;
tmp12 = z1 - z4;
tmp23 = RIGHT_SHIFT(z1 - ((z2 + z3 - z4) << 1), /* c0 = (c4+c12-c8)*2 */
CONST_BITS-PASS1_BITS);
z1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
z2 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
z3 = MULTIPLY(z1 + z2, FIX(1.105676686)); /* c6 */
tmp13 = z3 + MULTIPLY(z1, FIX(0.273079590)); /* c2-c6 */
tmp14 = z3 - MULTIPLY(z2, FIX(1.719280954)); /* c6+c10 */
tmp15 = MULTIPLY(z1, FIX(0.613604268)) - /* c10 */
MULTIPLY(z2, FIX(1.378756276)); /* c2 */
tmp20 = tmp10 + tmp13;
tmp26 = tmp10 - tmp13;
tmp21 = tmp11 + tmp14;
tmp25 = tmp11 - tmp14;
tmp22 = tmp12 + tmp15;
tmp24 = tmp12 - tmp15;
/* Odd part */
z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
z4 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
tmp13 = z4 << CONST_BITS;
tmp14 = z1 + z3;
tmp11 = MULTIPLY(z1 + z2, FIX(1.334852607)); /* c3 */
tmp12 = MULTIPLY(tmp14, FIX(1.197448846)); /* c5 */
tmp10 = tmp11 + tmp12 + tmp13 - MULTIPLY(z1, FIX(1.126980169)); /* c3+c5-c1 */
tmp14 = MULTIPLY(tmp14, FIX(0.752406978)); /* c9 */
tmp16 = tmp14 - MULTIPLY(z1, FIX(1.061150426)); /* c9+c11-c13 */
z1 -= z2;
tmp15 = MULTIPLY(z1, FIX(0.467085129)) - tmp13; /* c11 */
tmp16 += tmp15;
z1 += z4;
z4 = MULTIPLY(z2 + z3, - FIX(0.158341681)) - tmp13; /* -c13 */
tmp11 += z4 - MULTIPLY(z2, FIX(0.424103948)); /* c3-c9-c13 */
tmp12 += z4 - MULTIPLY(z3, FIX(2.373959773)); /* c3+c5-c13 */
z4 = MULTIPLY(z3 - z2, FIX(1.405321284)); /* c1 */
tmp14 += z4 + tmp13 - MULTIPLY(z3, FIX(1.6906431334)); /* c1+c9-c11 */
tmp15 += z4 + MULTIPLY(z2, FIX(0.674957567)); /* c1+c11-c5 */
tmp13 = (z1 - z3) << PASS1_BITS;
/* Final output stage */
wsptr[7*0] = (int) RIGHT_SHIFT(tmp20 + tmp10, CONST_BITS-PASS1_BITS);
wsptr[7*13] = (int) RIGHT_SHIFT(tmp20 - tmp10, CONST_BITS-PASS1_BITS);
wsptr[7*1] = (int) RIGHT_SHIFT(tmp21 + tmp11, CONST_BITS-PASS1_BITS);
wsptr[7*12] = (int) RIGHT_SHIFT(tmp21 - tmp11, CONST_BITS-PASS1_BITS);
wsptr[7*2] = (int) RIGHT_SHIFT(tmp22 + tmp12, CONST_BITS-PASS1_BITS);
wsptr[7*11] = (int) RIGHT_SHIFT(tmp22 - tmp12, CONST_BITS-PASS1_BITS);
wsptr[7*3] = (int) (tmp23 + tmp13);
wsptr[7*10] = (int) (tmp23 - tmp13);
wsptr[7*4] = (int) RIGHT_SHIFT(tmp24 + tmp14, CONST_BITS-PASS1_BITS);
wsptr[7*9] = (int) RIGHT_SHIFT(tmp24 - tmp14, CONST_BITS-PASS1_BITS);
wsptr[7*5] = (int) RIGHT_SHIFT(tmp25 + tmp15, CONST_BITS-PASS1_BITS);
wsptr[7*8] = (int) RIGHT_SHIFT(tmp25 - tmp15, CONST_BITS-PASS1_BITS);
wsptr[7*6] = (int) RIGHT_SHIFT(tmp26 + tmp16, CONST_BITS-PASS1_BITS);
wsptr[7*7] = (int) RIGHT_SHIFT(tmp26 - tmp16, CONST_BITS-PASS1_BITS);
}
/* Pass 2: process 14 rows from work array, store into output array.
* 7-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/14).
*/
wsptr = workspace;
for (ctr = 0; ctr < 14; ctr++) {
outptr = output_buf[ctr] + output_col;
/* Even part */
/* Add fudge factor here for final descale. */
tmp23 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
tmp23 <<= CONST_BITS;
z1 = (INT32) wsptr[2];
z2 = (INT32) wsptr[4];
z3 = (INT32) wsptr[6];
tmp20 = MULTIPLY(z2 - z3, FIX(0.881747734)); /* c4 */
tmp22 = MULTIPLY(z1 - z2, FIX(0.314692123)); /* c6 */
tmp21 = tmp20 + tmp22 + tmp23 - MULTIPLY(z2, FIX(1.841218003)); /* c2+c4-c6 */
tmp10 = z1 + z3;
z2 -= tmp10;
tmp10 = MULTIPLY(tmp10, FIX(1.274162392)) + tmp23; /* c2 */
tmp20 += tmp10 - MULTIPLY(z3, FIX(0.077722536)); /* c2-c4-c6 */
tmp22 += tmp10 - MULTIPLY(z1, FIX(2.470602249)); /* c2+c4+c6 */
tmp23 += MULTIPLY(z2, FIX(1.414213562)); /* c0 */
/* Odd part */
z1 = (INT32) wsptr[1];
z2 = (INT32) wsptr[3];
z3 = (INT32) wsptr[5];
tmp11 = MULTIPLY(z1 + z2, FIX(0.935414347)); /* (c3+c1-c5)/2 */
tmp12 = MULTIPLY(z1 - z2, FIX(0.170262339)); /* (c3+c5-c1)/2 */
tmp10 = tmp11 - tmp12;
tmp11 += tmp12;
tmp12 = MULTIPLY(z2 + z3, - FIX(1.378756276)); /* -c1 */
tmp11 += tmp12;
z2 = MULTIPLY(z1 + z3, FIX(0.613604268)); /* c5 */
tmp10 += z2;
tmp12 += z2 + MULTIPLY(z3, FIX(1.870828693)); /* c3+c1-c5 */
/* Final output stage */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp20 + tmp10,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[6] = range_limit[(int) RIGHT_SHIFT(tmp20 - tmp10,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp21 + tmp11,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp21 - tmp11,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp22 + tmp12,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp22 - tmp12,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp23,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
wsptr += 7; /* advance pointer to next row */
}
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a 6x12 output block.
*
* 12-point IDCT in pass 1 (columns), 6-point in pass 2 (rows).
*/
void
jpeg_idct_6x12 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp10, tmp11, tmp12, tmp13, tmp14, tmp15;
INT32 tmp20, tmp21, tmp22, tmp23, tmp24, tmp25;
INT32 z1, z2, z3, z4;
JCOEFPTR inptr;
ISLOW_MULT_TYPE * quantptr;
int * wsptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
int workspace[6*12]; /* buffers data between passes */
SHIFT_TEMPS
/* Pass 1: process columns from input, store into work array.
* 12-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/24).
*/
inptr = coef_block;
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
wsptr = workspace;
for (ctr = 0; ctr < 6; ctr++, inptr++, quantptr++, wsptr++) {
/* Even part */
z3 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
z3 <<= CONST_BITS;
/* Add fudge factor here for final descale. */
z3 += ONE << (CONST_BITS-PASS1_BITS-1);
z4 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
z4 = MULTIPLY(z4, FIX(1.224744871)); /* c4 */
tmp10 = z3 + z4;
tmp11 = z3 - z4;
z1 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
z4 = MULTIPLY(z1, FIX(1.366025404)); /* c2 */
z1 <<= CONST_BITS;
z2 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
z2 <<= CONST_BITS;
tmp12 = z1 - z2;
tmp21 = z3 + tmp12;
tmp24 = z3 - tmp12;
tmp12 = z4 + z2;
tmp20 = tmp10 + tmp12;
tmp25 = tmp10 - tmp12;
tmp12 = z4 - z1 - z2;
tmp22 = tmp11 + tmp12;
tmp23 = tmp11 - tmp12;
/* Odd part */
z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
z4 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
tmp11 = MULTIPLY(z2, FIX(1.306562965)); /* c3 */
tmp14 = MULTIPLY(z2, - FIX_0_541196100); /* -c9 */
tmp10 = z1 + z3;
tmp15 = MULTIPLY(tmp10 + z4, FIX(0.860918669)); /* c7 */
tmp12 = tmp15 + MULTIPLY(tmp10, FIX(0.261052384)); /* c5-c7 */
tmp10 = tmp12 + tmp11 + MULTIPLY(z1, FIX(0.280143716)); /* c1-c5 */
tmp13 = MULTIPLY(z3 + z4, - FIX(1.045510580)); /* -(c7+c11) */
tmp12 += tmp13 + tmp14 - MULTIPLY(z3, FIX(1.478575242)); /* c1+c5-c7-c11 */
tmp13 += tmp15 - tmp11 + MULTIPLY(z4, FIX(1.586706681)); /* c1+c11 */
tmp15 += tmp14 - MULTIPLY(z1, FIX(0.676326758)) - /* c7-c11 */
MULTIPLY(z4, FIX(1.982889723)); /* c5+c7 */
z1 -= z4;
z2 -= z3;
z3 = MULTIPLY(z1 + z2, FIX_0_541196100); /* c9 */
tmp11 = z3 + MULTIPLY(z1, FIX_0_765366865); /* c3-c9 */
tmp14 = z3 - MULTIPLY(z2, FIX_1_847759065); /* c3+c9 */
/* Final output stage */
wsptr[6*0] = (int) RIGHT_SHIFT(tmp20 + tmp10, CONST_BITS-PASS1_BITS);
wsptr[6*11] = (int) RIGHT_SHIFT(tmp20 - tmp10, CONST_BITS-PASS1_BITS);
wsptr[6*1] = (int) RIGHT_SHIFT(tmp21 + tmp11, CONST_BITS-PASS1_BITS);
wsptr[6*10] = (int) RIGHT_SHIFT(tmp21 - tmp11, CONST_BITS-PASS1_BITS);
wsptr[6*2] = (int) RIGHT_SHIFT(tmp22 + tmp12, CONST_BITS-PASS1_BITS);
wsptr[6*9] = (int) RIGHT_SHIFT(tmp22 - tmp12, CONST_BITS-PASS1_BITS);
wsptr[6*3] = (int) RIGHT_SHIFT(tmp23 + tmp13, CONST_BITS-PASS1_BITS);
wsptr[6*8] = (int) RIGHT_SHIFT(tmp23 - tmp13, CONST_BITS-PASS1_BITS);
wsptr[6*4] = (int) RIGHT_SHIFT(tmp24 + tmp14, CONST_BITS-PASS1_BITS);
wsptr[6*7] = (int) RIGHT_SHIFT(tmp24 - tmp14, CONST_BITS-PASS1_BITS);
wsptr[6*5] = (int) RIGHT_SHIFT(tmp25 + tmp15, CONST_BITS-PASS1_BITS);
wsptr[6*6] = (int) RIGHT_SHIFT(tmp25 - tmp15, CONST_BITS-PASS1_BITS);
}
/* Pass 2: process 12 rows from work array, store into output array.
* 6-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/12).
*/
wsptr = workspace;
for (ctr = 0; ctr < 12; ctr++) {
outptr = output_buf[ctr] + output_col;
/* Even part */
/* Add fudge factor here for final descale. */
tmp10 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
tmp10 <<= CONST_BITS;
tmp12 = (INT32) wsptr[4];
tmp20 = MULTIPLY(tmp12, FIX(0.707106781)); /* c4 */
tmp11 = tmp10 + tmp20;
tmp21 = tmp10 - tmp20 - tmp20;
tmp20 = (INT32) wsptr[2];
tmp10 = MULTIPLY(tmp20, FIX(1.224744871)); /* c2 */
tmp20 = tmp11 + tmp10;
tmp22 = tmp11 - tmp10;
/* Odd part */
z1 = (INT32) wsptr[1];
z2 = (INT32) wsptr[3];
z3 = (INT32) wsptr[5];
tmp11 = MULTIPLY(z1 + z3, FIX(0.366025404)); /* c5 */
tmp10 = tmp11 + ((z1 + z2) << CONST_BITS);
tmp12 = tmp11 + ((z3 - z2) << CONST_BITS);
tmp11 = (z1 - z2 - z3) << CONST_BITS;
/* Final output stage */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp20 + tmp10,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[5] = range_limit[(int) RIGHT_SHIFT(tmp20 - tmp10,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp21 + tmp11,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp21 - tmp11,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp22 + tmp12,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp22 - tmp12,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
wsptr += 6; /* advance pointer to next row */
}
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a 5x10 output block.
*
* 10-point IDCT in pass 1 (columns), 5-point in pass 2 (rows).
*/
void
jpeg_idct_5x10 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp10, tmp11, tmp12, tmp13, tmp14;
INT32 tmp20, tmp21, tmp22, tmp23, tmp24;
INT32 z1, z2, z3, z4, z5;
JCOEFPTR inptr;
ISLOW_MULT_TYPE * quantptr;
int * wsptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
int workspace[5*10]; /* buffers data between passes */
SHIFT_TEMPS
/* Pass 1: process columns from input, store into work array.
* 10-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/20).
*/
inptr = coef_block;
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
wsptr = workspace;
for (ctr = 0; ctr < 5; ctr++, inptr++, quantptr++, wsptr++) {
/* Even part */
z3 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
z3 <<= CONST_BITS;
/* Add fudge factor here for final descale. */
z3 += ONE << (CONST_BITS-PASS1_BITS-1);
z4 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
z1 = MULTIPLY(z4, FIX(1.144122806)); /* c4 */
z2 = MULTIPLY(z4, FIX(0.437016024)); /* c8 */
tmp10 = z3 + z1;
tmp11 = z3 - z2;
tmp22 = RIGHT_SHIFT(z3 - ((z1 - z2) << 1), /* c0 = (c4-c8)*2 */
CONST_BITS-PASS1_BITS);
z2 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
z3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
z1 = MULTIPLY(z2 + z3, FIX(0.831253876)); /* c6 */
tmp12 = z1 + MULTIPLY(z2, FIX(0.513743148)); /* c2-c6 */
tmp13 = z1 - MULTIPLY(z3, FIX(2.176250899)); /* c2+c6 */
tmp20 = tmp10 + tmp12;
tmp24 = tmp10 - tmp12;
tmp21 = tmp11 + tmp13;
tmp23 = tmp11 - tmp13;
/* Odd part */
z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
z4 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
tmp11 = z2 + z4;
tmp13 = z2 - z4;
tmp12 = MULTIPLY(tmp13, FIX(0.309016994)); /* (c3-c7)/2 */
z5 = z3 << CONST_BITS;
z2 = MULTIPLY(tmp11, FIX(0.951056516)); /* (c3+c7)/2 */
z4 = z5 + tmp12;
tmp10 = MULTIPLY(z1, FIX(1.396802247)) + z2 + z4; /* c1 */
tmp14 = MULTIPLY(z1, FIX(0.221231742)) - z2 + z4; /* c9 */
z2 = MULTIPLY(tmp11, FIX(0.587785252)); /* (c1-c9)/2 */
z4 = z5 - tmp12 - (tmp13 << (CONST_BITS - 1));
tmp12 = (z1 - tmp13 - z3) << PASS1_BITS;
tmp11 = MULTIPLY(z1, FIX(1.260073511)) - z2 - z4; /* c3 */
tmp13 = MULTIPLY(z1, FIX(0.642039522)) - z2 + z4; /* c7 */
/* Final output stage */
wsptr[5*0] = (int) RIGHT_SHIFT(tmp20 + tmp10, CONST_BITS-PASS1_BITS);
wsptr[5*9] = (int) RIGHT_SHIFT(tmp20 - tmp10, CONST_BITS-PASS1_BITS);
wsptr[5*1] = (int) RIGHT_SHIFT(tmp21 + tmp11, CONST_BITS-PASS1_BITS);
wsptr[5*8] = (int) RIGHT_SHIFT(tmp21 - tmp11, CONST_BITS-PASS1_BITS);
wsptr[5*2] = (int) (tmp22 + tmp12);
wsptr[5*7] = (int) (tmp22 - tmp12);
wsptr[5*3] = (int) RIGHT_SHIFT(tmp23 + tmp13, CONST_BITS-PASS1_BITS);
wsptr[5*6] = (int) RIGHT_SHIFT(tmp23 - tmp13, CONST_BITS-PASS1_BITS);
wsptr[5*4] = (int) RIGHT_SHIFT(tmp24 + tmp14, CONST_BITS-PASS1_BITS);
wsptr[5*5] = (int) RIGHT_SHIFT(tmp24 - tmp14, CONST_BITS-PASS1_BITS);
}
/* Pass 2: process 10 rows from work array, store into output array.
* 5-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/10).
*/
wsptr = workspace;
for (ctr = 0; ctr < 10; ctr++) {
outptr = output_buf[ctr] + output_col;
/* Even part */
/* Add fudge factor here for final descale. */
tmp12 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
tmp12 <<= CONST_BITS;
tmp13 = (INT32) wsptr[2];
tmp14 = (INT32) wsptr[4];
z1 = MULTIPLY(tmp13 + tmp14, FIX(0.790569415)); /* (c2+c4)/2 */
z2 = MULTIPLY(tmp13 - tmp14, FIX(0.353553391)); /* (c2-c4)/2 */
z3 = tmp12 + z2;
tmp10 = z3 + z1;
tmp11 = z3 - z1;
tmp12 -= z2 << 2;
/* Odd part */
z2 = (INT32) wsptr[1];
z3 = (INT32) wsptr[3];
z1 = MULTIPLY(z2 + z3, FIX(0.831253876)); /* c3 */
tmp13 = z1 + MULTIPLY(z2, FIX(0.513743148)); /* c1-c3 */
tmp14 = z1 - MULTIPLY(z3, FIX(2.176250899)); /* c1+c3 */
/* Final output stage */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp13,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[4] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp13,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp11 + tmp14,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp11 - tmp14,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp12,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
wsptr += 5; /* advance pointer to next row */
}
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a 4x8 output block.
*
* 8-point IDCT in pass 1 (columns), 4-point in pass 2 (rows).
*/
void
jpeg_idct_4x8 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp0, tmp1, tmp2, tmp3;
INT32 tmp10, tmp11, tmp12, tmp13;
INT32 z1, z2, z3;
JCOEFPTR inptr;
ISLOW_MULT_TYPE * quantptr;
int * wsptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
int workspace[4*8]; /* buffers data between passes */
SHIFT_TEMPS
/* Pass 1: process columns from input, store into work array. */
/* Note results are scaled up by sqrt(8) compared to a true IDCT; */
/* furthermore, we scale the results by 2**PASS1_BITS. */
inptr = coef_block;
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
wsptr = workspace;
for (ctr = 4; ctr > 0; ctr--) {
/* Due to quantization, we will usually find that many of the input
* coefficients are zero, especially the AC terms. We can exploit this
* by short-circuiting the IDCT calculation for any column in which all
* the AC terms are zero. In that case each output is equal to the
* DC coefficient (with scale factor as needed).
* With typical images and quantization tables, half or more of the
* column DCT calculations can be simplified this way.
*/
if (inptr[DCTSIZE*1] == 0 && inptr[DCTSIZE*2] == 0 &&
inptr[DCTSIZE*3] == 0 && inptr[DCTSIZE*4] == 0 &&
inptr[DCTSIZE*5] == 0 && inptr[DCTSIZE*6] == 0 &&
inptr[DCTSIZE*7] == 0) {
/* AC terms all zero */
int dcval = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]) << PASS1_BITS;
wsptr[4*0] = dcval;
wsptr[4*1] = dcval;
wsptr[4*2] = dcval;
wsptr[4*3] = dcval;
wsptr[4*4] = dcval;
wsptr[4*5] = dcval;
wsptr[4*6] = dcval;
wsptr[4*7] = dcval;
inptr++; /* advance pointers to next column */
quantptr++;
wsptr++;
continue;
}
/* Even part: reverse the even part of the forward DCT. */
/* The rotator is sqrt(2)*c(-6). */
z2 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
z3 = DEQUANTIZE(inptr[DCTSIZE*6], quantptr[DCTSIZE*6]);
z1 = MULTIPLY(z2 + z3, FIX_0_541196100);
tmp2 = z1 + MULTIPLY(z2, FIX_0_765366865);
tmp3 = z1 - MULTIPLY(z3, FIX_1_847759065);
z2 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
z3 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
z2 <<= CONST_BITS;
z3 <<= CONST_BITS;
/* Add fudge factor here for final descale. */
z2 += ONE << (CONST_BITS-PASS1_BITS-1);
tmp0 = z2 + z3;
tmp1 = z2 - z3;
tmp10 = tmp0 + tmp2;
tmp13 = tmp0 - tmp2;
tmp11 = tmp1 + tmp3;
tmp12 = tmp1 - tmp3;
/* Odd part per figure 8; the matrix is unitary and hence its
* transpose is its inverse. i0..i3 are y7,y5,y3,y1 respectively.
*/
tmp0 = DEQUANTIZE(inptr[DCTSIZE*7], quantptr[DCTSIZE*7]);
tmp1 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
tmp2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
tmp3 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
z2 = tmp0 + tmp2;
z3 = tmp1 + tmp3;
z1 = MULTIPLY(z2 + z3, FIX_1_175875602); /* sqrt(2) * c3 */
z2 = MULTIPLY(z2, - FIX_1_961570560); /* sqrt(2) * (-c3-c5) */
z3 = MULTIPLY(z3, - FIX_0_390180644); /* sqrt(2) * (c5-c3) */
z2 += z1;
z3 += z1;
z1 = MULTIPLY(tmp0 + tmp3, - FIX_0_899976223); /* sqrt(2) * (c7-c3) */
tmp0 = MULTIPLY(tmp0, FIX_0_298631336); /* sqrt(2) * (-c1+c3+c5-c7) */
tmp3 = MULTIPLY(tmp3, FIX_1_501321110); /* sqrt(2) * ( c1+c3-c5-c7) */
tmp0 += z1 + z2;
tmp3 += z1 + z3;
z1 = MULTIPLY(tmp1 + tmp2, - FIX_2_562915447); /* sqrt(2) * (-c1-c3) */
tmp1 = MULTIPLY(tmp1, FIX_2_053119869); /* sqrt(2) * ( c1+c3-c5+c7) */
tmp2 = MULTIPLY(tmp2, FIX_3_072711026); /* sqrt(2) * ( c1+c3+c5-c7) */
tmp1 += z1 + z3;
tmp2 += z1 + z2;
/* Final output stage: inputs are tmp10..tmp13, tmp0..tmp3 */
wsptr[4*0] = (int) RIGHT_SHIFT(tmp10 + tmp3, CONST_BITS-PASS1_BITS);
wsptr[4*7] = (int) RIGHT_SHIFT(tmp10 - tmp3, CONST_BITS-PASS1_BITS);
wsptr[4*1] = (int) RIGHT_SHIFT(tmp11 + tmp2, CONST_BITS-PASS1_BITS);
wsptr[4*6] = (int) RIGHT_SHIFT(tmp11 - tmp2, CONST_BITS-PASS1_BITS);
wsptr[4*2] = (int) RIGHT_SHIFT(tmp12 + tmp1, CONST_BITS-PASS1_BITS);
wsptr[4*5] = (int) RIGHT_SHIFT(tmp12 - tmp1, CONST_BITS-PASS1_BITS);
wsptr[4*3] = (int) RIGHT_SHIFT(tmp13 + tmp0, CONST_BITS-PASS1_BITS);
wsptr[4*4] = (int) RIGHT_SHIFT(tmp13 - tmp0, CONST_BITS-PASS1_BITS);
inptr++; /* advance pointers to next column */
quantptr++;
wsptr++;
}
/* Pass 2: process 8 rows from work array, store into output array.
* 4-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/16).
*/
wsptr = workspace;
for (ctr = 0; ctr < 8; ctr++) {
outptr = output_buf[ctr] + output_col;
/* Even part */
/* Add fudge factor here for final descale. */
tmp0 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
tmp2 = (INT32) wsptr[2];
tmp10 = (tmp0 + tmp2) << CONST_BITS;
tmp12 = (tmp0 - tmp2) << CONST_BITS;
/* Odd part */
/* Same rotation as in the even part of the 8x8 LL&M IDCT */
z2 = (INT32) wsptr[1];
z3 = (INT32) wsptr[3];
z1 = MULTIPLY(z2 + z3, FIX_0_541196100); /* c6 */
tmp0 = z1 + MULTIPLY(z2, FIX_0_765366865); /* c2-c6 */
tmp2 = z1 - MULTIPLY(z3, FIX_1_847759065); /* c2+c6 */
/* Final output stage */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp0,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[3] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp0,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp12 + tmp2,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp12 - tmp2,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
wsptr += 4; /* advance pointer to next row */
}
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a reduced-size 3x6 output block.
*
* 6-point IDCT in pass 1 (columns), 3-point in pass 2 (rows).
*/
void
jpeg_idct_3x6 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp0, tmp1, tmp2, tmp10, tmp11, tmp12;
INT32 z1, z2, z3;
JCOEFPTR inptr;
ISLOW_MULT_TYPE * quantptr;
int * wsptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
int workspace[3*6]; /* buffers data between passes */
SHIFT_TEMPS
/* Pass 1: process columns from input, store into work array.
* 6-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/12).
*/
inptr = coef_block;
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
wsptr = workspace;
for (ctr = 0; ctr < 3; ctr++, inptr++, quantptr++, wsptr++) {
/* Even part */
tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
tmp0 <<= CONST_BITS;
/* Add fudge factor here for final descale. */
tmp0 += ONE << (CONST_BITS-PASS1_BITS-1);
tmp2 = DEQUANTIZE(inptr[DCTSIZE*4], quantptr[DCTSIZE*4]);
tmp10 = MULTIPLY(tmp2, FIX(0.707106781)); /* c4 */
tmp1 = tmp0 + tmp10;
tmp11 = RIGHT_SHIFT(tmp0 - tmp10 - tmp10, CONST_BITS-PASS1_BITS);
tmp10 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
tmp0 = MULTIPLY(tmp10, FIX(1.224744871)); /* c2 */
tmp10 = tmp1 + tmp0;
tmp12 = tmp1 - tmp0;
/* Odd part */
z1 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
z2 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
z3 = DEQUANTIZE(inptr[DCTSIZE*5], quantptr[DCTSIZE*5]);
tmp1 = MULTIPLY(z1 + z3, FIX(0.366025404)); /* c5 */
tmp0 = tmp1 + ((z1 + z2) << CONST_BITS);
tmp2 = tmp1 + ((z3 - z2) << CONST_BITS);
tmp1 = (z1 - z2 - z3) << PASS1_BITS;
/* Final output stage */
wsptr[3*0] = (int) RIGHT_SHIFT(tmp10 + tmp0, CONST_BITS-PASS1_BITS);
wsptr[3*5] = (int) RIGHT_SHIFT(tmp10 - tmp0, CONST_BITS-PASS1_BITS);
wsptr[3*1] = (int) (tmp11 + tmp1);
wsptr[3*4] = (int) (tmp11 - tmp1);
wsptr[3*2] = (int) RIGHT_SHIFT(tmp12 + tmp2, CONST_BITS-PASS1_BITS);
wsptr[3*3] = (int) RIGHT_SHIFT(tmp12 - tmp2, CONST_BITS-PASS1_BITS);
}
/* Pass 2: process 6 rows from work array, store into output array.
* 3-point IDCT kernel, cK represents sqrt(2) * cos(K*pi/6).
*/
wsptr = workspace;
for (ctr = 0; ctr < 6; ctr++) {
outptr = output_buf[ctr] + output_col;
/* Even part */
/* Add fudge factor here for final descale. */
tmp0 = (INT32) wsptr[0] + (ONE << (PASS1_BITS+2));
tmp0 <<= CONST_BITS;
tmp2 = (INT32) wsptr[2];
tmp12 = MULTIPLY(tmp2, FIX(0.707106781)); /* c2 */
tmp10 = tmp0 + tmp12;
tmp2 = tmp0 - tmp12 - tmp12;
/* Odd part */
tmp12 = (INT32) wsptr[1];
tmp0 = MULTIPLY(tmp12, FIX(1.224744871)); /* c1 */
/* Final output stage */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp0,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[2] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp0,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp2,
CONST_BITS+PASS1_BITS+3)
& RANGE_MASK];
wsptr += 3; /* advance pointer to next row */
}
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a 2x4 output block.
*
* 4-point IDCT in pass 1 (columns), 2-point in pass 2 (rows).
*/
void
jpeg_idct_2x4 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp0, tmp2, tmp10, tmp12;
INT32 z1, z2, z3;
JCOEFPTR inptr;
ISLOW_MULT_TYPE * quantptr;
INT32 * wsptr;
JSAMPROW outptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
int ctr;
INT32 workspace[2*4]; /* buffers data between passes */
SHIFT_TEMPS
/* Pass 1: process columns from input, store into work array.
* 4-point IDCT kernel,
* cK represents sqrt(2) * cos(K*pi/16) [refers to 8-point IDCT].
*/
inptr = coef_block;
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
wsptr = workspace;
for (ctr = 0; ctr < 2; ctr++, inptr++, quantptr++, wsptr++) {
/* Even part */
tmp0 = DEQUANTIZE(inptr[DCTSIZE*0], quantptr[DCTSIZE*0]);
tmp2 = DEQUANTIZE(inptr[DCTSIZE*2], quantptr[DCTSIZE*2]);
tmp10 = (tmp0 + tmp2) << CONST_BITS;
tmp12 = (tmp0 - tmp2) << CONST_BITS;
/* Odd part */
/* Same rotation as in the even part of the 8x8 LL&M IDCT */
z2 = DEQUANTIZE(inptr[DCTSIZE*1], quantptr[DCTSIZE*1]);
z3 = DEQUANTIZE(inptr[DCTSIZE*3], quantptr[DCTSIZE*3]);
z1 = MULTIPLY(z2 + z3, FIX_0_541196100); /* c6 */
tmp0 = z1 + MULTIPLY(z2, FIX_0_765366865); /* c2-c6 */
tmp2 = z1 - MULTIPLY(z3, FIX_1_847759065); /* c2+c6 */
/* Final output stage */
wsptr[2*0] = tmp10 + tmp0;
wsptr[2*3] = tmp10 - tmp0;
wsptr[2*1] = tmp12 + tmp2;
wsptr[2*2] = tmp12 - tmp2;
}
/* Pass 2: process 4 rows from work array, store into output array. */
wsptr = workspace;
for (ctr = 0; ctr < 4; ctr++) {
outptr = output_buf[ctr] + output_col;
/* Even part */
/* Add fudge factor here for final descale. */
tmp10 = wsptr[0] + (ONE << (CONST_BITS+2));
/* Odd part */
tmp0 = wsptr[1];
/* Final output stage */
outptr[0] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp0, CONST_BITS+3)
& RANGE_MASK];
outptr[1] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp0, CONST_BITS+3)
& RANGE_MASK];
wsptr += 2; /* advance pointer to next row */
}
}
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a 1x2 output block.
*
* 2-point IDCT in pass 1 (columns), 1-point in pass 2 (rows).
*/
void
jpeg_idct_1x2 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
JCOEFPTR coef_block,
JSAMPARRAY output_buf, JDIMENSION output_col)
{
INT32 tmp0, tmp10;
ISLOW_MULT_TYPE * quantptr;
JSAMPLE *range_limit = IDCT_range_limit(cinfo);
SHIFT_TEMPS
/* Process 1 column from input, store into output array. */
quantptr = (ISLOW_MULT_TYPE *) compptr->dct_table;
/* Even part */
tmp10 = DEQUANTIZE(coef_block[DCTSIZE*0], quantptr[DCTSIZE*0]);
/* Add fudge factor here for final descale. */
tmp10 += ONE << 2;
/* Odd part */
tmp0 = DEQUANTIZE(coef_block[DCTSIZE*1], quantptr[DCTSIZE*1]);
/* Final output stage */
output_buf[0][output_col] = range_limit[(int) RIGHT_SHIFT(tmp10 + tmp0, 3)
& RANGE_MASK];
output_buf[1][output_col] = range_limit[(int) RIGHT_SHIFT(tmp10 - tmp0, 3)
& RANGE_MASK];
}
#endif /* IDCT_SCALING_SUPPORTED */
#endif /* DCT_ISLOW_SUPPORTED */