/* [<][>][^][v][top][bottom][index][help] */
DEFINITIONS
This source file includes following definitions.
- DDSDecoder
- Min
- ReadDDSImage
- ReadDDSInfo
- CalculateColors
- ReadDXT1
- ReadDXT3
- ReadDXT5
- ReadUncompressedRGB
- ReadUncompressedRGBA
- SkipDXTMipmaps
- SkipRGBMipmaps
- IsDDS
- RegisterDDSImage
- UnregisterDDSImage
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% DDDD DDDD SSSSS %
% D D D D SS %
% D D D D SSS %
% D D D D SS %
% DDDD DDDD SSSSS %
% %
% %
% Read Microsoft Direct Draw Surface Image Format %
% %
% Software Design %
% Bianca van Schaik %
% March 2008 %
% %
% %
% Copyright 1999-2011 ImageMagick Studio LLC, a non-profit organization %
% dedicated to making software imaging solutions freely available. %
% %
% You may not use this file except in compliance with the License. You may %
% obtain a copy of the License at %
% %
% http://www.imagemagick.org/script/license.php %
% %
% Unless required by applicable law or agreed to in writing, software %
% distributed under the License is distributed on an "AS IS" BASIS, %
% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. %
% See the License for the specific language governing permissions and %
% limitations under the License. %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%
*/
/*
Include declarations.
*/
#include "magick/studio.h"
#include "magick/blob.h"
#include "magick/blob-private.h"
#include "magick/cache.h"
#include "magick/colorspace.h"
#include "magick/exception.h"
#include "magick/exception-private.h"
#include "magick/image.h"
#include "magick/image-private.h"
#include "magick/list.h"
#include "magick/log.h"
#include "magick/magick.h"
#include "magick/memory_.h"
#include "magick/monitor.h"
#include "magick/monitor-private.h"
#include "magick/profile.h"
#include "magick/quantum-private.h"
#include "magick/static.h"
#include "magick/string_.h"
#include "magick/module.h"
#include "magick/transform.h"
#include "magick/studio.h"
#include "magick/blob.h"
#include "magick/blob-private.h"
#include "magick/colorspace.h"
#include "magick/exception.h"
#include "magick/exception-private.h"
#include "magick/compress.h"
#include "magick/image.h"
#include "magick/image-private.h"
#include "magick/list.h"
#include "magick/magick.h"
#include "magick/memory_.h"
#include "magick/monitor.h"
#include "magick/monitor-private.h"
#include "magick/quantum.h"
#include "magick/static.h"
#include "magick/string_.h"
/*
Definitions
*/
#define DDSD_CAPS 0x00000001
#define DDSD_HEIGHT 0x00000002
#define DDSD_WIDTH 0x00000004
#define DDSD_PITCH 0x00000008
#define DDSD_PIXELFORMAT 0x00001000
#define DDSD_MIPMAPCOUNT 0x00020000
#define DDSD_LINEARSIZE 0x00080000
#define DDSD_DEPTH 0x00800000
#define DDPF_ALPHAPIXELS 0x00000001
#define DDPF_FOURCC 0x00000004
#define DDPF_RGB 0x00000040
#define FOURCC_DXT1 0x31545844
#define FOURCC_DXT3 0x33545844
#define FOURCC_DXT5 0x35545844
#define DDSCAPS_COMPLEX 0x00000008
#define DDSCAPS_TEXTURE 0x00001000
#define DDSCAPS_MIPMAP 0x00400000
#define DDSCAPS2_CUBEMAP 0x00000200
#define DDSCAPS2_CUBEMAP_POSITIVEX 0x00000400
#define DDSCAPS2_CUBEMAP_NEGATIVEX 0x00000800
#define DDSCAPS2_CUBEMAP_POSITIVEY 0x00001000
#define DDSCAPS2_CUBEMAP_NEGATIVEY 0x00002000
#define DDSCAPS2_CUBEMAP_POSITIVEZ 0x00004000
#define DDSCAPS2_CUBEMAP_NEGATIVEZ 0x00008000
#define DDSCAPS2_VOLUME 0x00200000
/*
Structure declarations.
*/
typedef struct _DDSPixelFormat
{
size_t
flags,
fourcc,
rgb_bitcount,
r_bitmask,
g_bitmask,
b_bitmask,
alpha_bitmask;
} DDSPixelFormat;
typedef struct _DDSInfo
{
size_t
flags,
height,
width,
pitchOrLinearSize,
depth,
mipmapcount,
ddscaps1,
ddscaps2;
DDSPixelFormat
pixelformat;
} DDSInfo;
typedef struct _DDSColors
{
unsigned char
r[4],
g[4],
b[4],
a[4];
} DDSColors;
typedef MagickBooleanType
DDSDecoder(Image *,DDSInfo *);
/*
Macros
*/
#define C565_r(x) (((x) & 0xF800) >> 11)
#define C565_g(x) (((x) & 0x07E0) >> 5)
#define C565_b(x) ((x) & 0x001F)
#define C565_red(x) ( (C565_r(x) << 3 | C565_r(x) >> 2))
#define C565_green(x) ( (C565_g(x) << 2 | C565_g(x) >> 4))
#define C565_blue(x) ( (C565_b(x) << 3 | C565_b(x) >> 2))
#define DIV2(x) ((x) > 1 ? ((x) >> 1) : 1)
/*
Forward declarations
*/
static MagickBooleanType
ReadDDSInfo(Image *image, DDSInfo *dds_info);
static void
CalculateColors(unsigned short c0, unsigned short c1,
DDSColors *c, MagickBooleanType ignoreAlpha);
static MagickBooleanType
ReadDXT1(Image *image, DDSInfo *dds_info);
static MagickBooleanType
ReadDXT3(Image *image, DDSInfo *dds_info);
static MagickBooleanType
ReadDXT5(Image *image, DDSInfo *dds_info);
static MagickBooleanType
ReadUncompressedRGB(Image *image, DDSInfo *dds_info);
static MagickBooleanType
ReadUncompressedRGBA(Image *image, DDSInfo *dds_info);
static void
SkipDXTMipmaps(Image *image, DDSInfo *dds_info, int texel_size);
static void
SkipRGBMipmaps(Image *image, DDSInfo *dds_info, int pixel_size);
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% R e a d D D S I m a g e %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% ReadDDSImage() reads a DirectDraw Surface image file and returns it. It
% allocates the memory necessary for the new Image structure and returns a
% pointer to the new image.
%
% The format of the ReadDDSImage method is:
%
% Image *ReadDDSImage(const ImageInfo *image_info,ExceptionInfo *exception)
%
% A description of each parameter follows:
%
% o image_info: The image info.
%
% o exception: return any errors or warnings in this structure.
%
*/
static inline size_t Min(size_t one, size_t two)
{
if (one < two)
return one;
return two;
}
static Image *ReadDDSImage(const ImageInfo *image_info,ExceptionInfo *exception)
{
Image
*image;
MagickBooleanType
status,
cubemap = MagickFalse,
volume = MagickFalse,
matte;
CompressionType
compression;
DDSInfo
dds_info;
DDSDecoder
*decoder;
size_t
n, num_images;
/*
Open image file.
*/
assert(image_info != (const ImageInfo *) NULL);
assert(image_info->signature == MagickSignature);
if (image_info->debug != MagickFalse)
(void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",
image_info->filename);
assert(exception != (ExceptionInfo *) NULL);
assert(exception->signature == MagickSignature);
image=AcquireImage(image_info);
status=OpenBlob(image_info,image,ReadBinaryBlobMode,exception);
if (status == MagickFalse)
{
image=DestroyImageList(image);
return((Image *) NULL);
}
/*
Initialize image structure.
*/
if (ReadDDSInfo(image, &dds_info) != MagickTrue) {
ThrowReaderException(CorruptImageError,"ImproperImageHeader");
}
if (dds_info.ddscaps2 & DDSCAPS2_CUBEMAP)
cubemap = MagickTrue;
if (dds_info.ddscaps2 & DDSCAPS2_VOLUME && dds_info.depth > 0)
volume = MagickTrue;
(void) SeekBlob(image, 128, SEEK_SET);
/*
Determine pixel format
*/
if (dds_info.pixelformat.flags & DDPF_RGB)
{
compression = NoCompression;
if (dds_info.pixelformat.flags & DDPF_ALPHAPIXELS)
{
matte = MagickTrue;
decoder = ReadUncompressedRGBA;
}
else
{
matte = MagickTrue;
decoder = ReadUncompressedRGB;
}
}
else if (dds_info.pixelformat.flags & DDPF_FOURCC)
{
switch (dds_info.pixelformat.fourcc)
{
case FOURCC_DXT1:
{
matte = MagickFalse;
compression = DXT1Compression;
decoder = ReadDXT1;
break;
}
case FOURCC_DXT3:
{
matte = MagickTrue;
compression = DXT3Compression;
decoder = ReadDXT3;
break;
}
case FOURCC_DXT5:
{
matte = MagickTrue;
compression = DXT5Compression;
decoder = ReadDXT5;
break;
}
default:
{
/* Unknown FOURCC */
ThrowReaderException(CorruptImageError, "ImageTypeNotSupported");
}
}
}
else
{
/* Neither compressed nor uncompressed... thus unsupported */
ThrowReaderException(CorruptImageError, "ImageTypeNotSupported");
}
num_images = 1;
if (cubemap)
{
/*
Determine number of faces defined in the cubemap
*/
num_images = 0;
if (dds_info.ddscaps2 & DDSCAPS2_CUBEMAP_POSITIVEX) num_images++;
if (dds_info.ddscaps2 & DDSCAPS2_CUBEMAP_NEGATIVEX) num_images++;
if (dds_info.ddscaps2 & DDSCAPS2_CUBEMAP_POSITIVEY) num_images++;
if (dds_info.ddscaps2 & DDSCAPS2_CUBEMAP_NEGATIVEY) num_images++;
if (dds_info.ddscaps2 & DDSCAPS2_CUBEMAP_POSITIVEZ) num_images++;
if (dds_info.ddscaps2 & DDSCAPS2_CUBEMAP_NEGATIVEZ) num_images++;
}
if (volume)
num_images = dds_info.depth;
for (n = 0; n < num_images; n++)
{
if (n != 0)
{
/* Start a new image */
AcquireNextImage(image_info,image);
if (GetNextImageInList(image) == (Image *) NULL)
{
image = DestroyImageList(image);
return((Image *) NULL);
}
image=SyncNextImageInList(image);
}
image->matte = matte;
image->compression = compression;
image->columns = dds_info.width;
image->rows = dds_info.height;
image->storage_class = DirectClass;
image->endian = LSBEndian;
image->depth = 8;
if (image_info->ping != MagickFalse)
{
(void) CloseBlob(image);
return(GetFirstImageInList(image));
}
if ((decoder)(image, &dds_info) != MagickTrue)
{
(void) CloseBlob(image);
return(GetFirstImageInList(image));
}
}
if (EOFBlob(image) != MagickFalse)
ThrowFileException(exception,CorruptImageError,"UnexpectedEndOfFile",
image->filename);
(void) CloseBlob(image);
return(GetFirstImageInList(image));
}
static MagickBooleanType ReadDDSInfo(Image *image, DDSInfo *dds_info)
{
size_t
hdr_size,
required;
/* Seek to start of header */
(void) SeekBlob(image, 4, SEEK_SET);
/* Check header field */
hdr_size = ReadBlobLSBLong(image);
if (hdr_size != 124)
return MagickFalse;
/* Fill in DDS info struct */
dds_info->flags = ReadBlobLSBLong(image);
/* Check required flags */
required=(size_t) (DDSD_WIDTH | DDSD_HEIGHT | DDSD_PIXELFORMAT);
if ((dds_info->flags & required) != required)
return MagickFalse;
dds_info->height = ReadBlobLSBLong(image);
dds_info->width = ReadBlobLSBLong(image);
dds_info->pitchOrLinearSize = ReadBlobLSBLong(image);
dds_info->depth = ReadBlobLSBLong(image);
dds_info->mipmapcount = ReadBlobLSBLong(image);
(void) SeekBlob(image, 44, SEEK_CUR); /* reserved region of 11 DWORDs */
/* Read pixel format structure */
hdr_size = ReadBlobLSBLong(image);
if (hdr_size != 32)
return MagickFalse;
dds_info->pixelformat.flags = ReadBlobLSBLong(image);
dds_info->pixelformat.fourcc = ReadBlobLSBLong(image);
dds_info->pixelformat.rgb_bitcount = ReadBlobLSBLong(image);
dds_info->pixelformat.r_bitmask = ReadBlobLSBLong(image);
dds_info->pixelformat.g_bitmask = ReadBlobLSBLong(image);
dds_info->pixelformat.b_bitmask = ReadBlobLSBLong(image);
dds_info->pixelformat.alpha_bitmask = ReadBlobLSBLong(image);
dds_info->ddscaps1 = ReadBlobLSBLong(image);
dds_info->ddscaps2 = ReadBlobLSBLong(image);
(void) SeekBlob(image, 12, SEEK_CUR); /* 3 reserved DWORDs */
return MagickTrue;
}
static void CalculateColors(unsigned short c0, unsigned short c1,
DDSColors *c, MagickBooleanType ignoreAlpha)
{
c->a[0] = c->a[1] = c->a[2] = c->a[3] = 0;
c->r[0] = (unsigned char) C565_red(c0);
c->g[0] = (unsigned char) C565_green(c0);
c->b[0] = (unsigned char) C565_blue(c0);
c->r[1] = (unsigned char) C565_red(c1);
c->g[1] = (unsigned char) C565_green(c1);
c->b[1] = (unsigned char) C565_blue(c1);
if (ignoreAlpha == MagickTrue || c0 > c1)
{
c->r[2] = (unsigned char) ((2 * c->r[0] + c->r[1]) / 3);
c->g[2] = (unsigned char) ((2 * c->g[0] + c->g[1]) / 3);
c->b[2] = (unsigned char) ((2 * c->b[0] + c->b[1]) / 3);
c->r[3] = (unsigned char) ((c->r[0] + 2 * c->r[1]) / 3);
c->g[3] = (unsigned char) ((c->g[0] + 2 * c->g[1]) / 3);
c->b[3] = (unsigned char) ((c->b[0] + 2 * c->b[1]) / 3);
}
else
{
c->r[2] = (unsigned char) ((c->r[0] + c->r[1]) / 2);
c->g[2] = (unsigned char) ((c->g[0] + c->g[1]) / 2);
c->b[2] = (unsigned char) ((c->b[0] + c->b[1]) / 2);
c->r[3] = c->g[3] = c->b[3] = 0;
c->a[3] = 255;
}
}
static MagickBooleanType ReadDXT1(Image *image, DDSInfo *dds_info)
{
DDSColors
colors;
ExceptionInfo
*exception;
ssize_t
j,
y;
PixelPacket
*q;
register ssize_t
i,
x;
unsigned char
code;
unsigned short
c0,
c1;
size_t
bits;
exception=(&image->exception);
for (y = 0; y < (ssize_t) dds_info->height; y += 4)
{
for (x = 0; x < (ssize_t) dds_info->width; x += 4)
{
/* Get 4x4 patch of pixels to write on */
q = QueueAuthenticPixels(image, x, y, Min(4, dds_info->width - x),
Min(4, dds_info->height - y),exception);
if (q == (PixelPacket *) NULL)
return MagickFalse;
/* Read 8 bytes of data from the image */
c0 = ReadBlobLSBShort(image);
c1 = ReadBlobLSBShort(image);
bits = ReadBlobLSBLong(image);
CalculateColors(c0, c1, &colors, MagickFalse);
/* Write the pixels */
for (j = 0; j < 4; j++)
{
for (i = 0; i < 4; i++)
{
if ((x + i) < (ssize_t) dds_info->width && (y + j) < (ssize_t) dds_info->height)
{
code = (unsigned char) ((bits >> ((j*4+i)*2)) & 0x3);
q->red = ScaleCharToQuantum( colors.r[code] );
q->green = ScaleCharToQuantum( colors.g[code] );
q->blue = ScaleCharToQuantum( colors.b[code] );
q->opacity = ScaleCharToQuantum( colors.a[code] );
if (colors.a[code] && image->matte == MagickFalse)
/* Correct matte */
image->matte = MagickTrue;
q++;
}
}
}
if (SyncAuthenticPixels(image,exception) == MagickFalse)
return MagickFalse;
}
}
SkipDXTMipmaps(image, dds_info, 8);
return MagickTrue;
}
static MagickBooleanType ReadDXT3(Image *image, DDSInfo *dds_info)
{
DDSColors
colors;
ExceptionInfo
*exception;
ssize_t
j,
y;
PixelPacket
*q;
register ssize_t
i,
x;
unsigned char
alpha;
size_t
a0,
a1,
bits,
code;
unsigned short
c0,
c1;
exception=(&image->exception);
for (y = 0; y < (ssize_t) dds_info->height; y += 4)
{
for (x = 0; x < (ssize_t) dds_info->width; x += 4)
{
/* Get 4x4 patch of pixels to write on */
q = QueueAuthenticPixels(image, x, y, Min(4, dds_info->width - x),
Min(4, dds_info->height - y),exception);
if (q == (PixelPacket *) NULL)
return MagickFalse;
/* Read alpha values (8 bytes) */
a0 = ReadBlobLSBLong(image);
a1 = ReadBlobLSBLong(image);
/* Read 8 bytes of data from the image */
c0 = ReadBlobLSBShort(image);
c1 = ReadBlobLSBShort(image);
bits = ReadBlobLSBLong(image);
CalculateColors(c0, c1, &colors, MagickTrue);
/* Write the pixels */
for (j = 0; j < 4; j++)
{
for (i = 0; i < 4; i++)
{
if ((x + i) < (ssize_t) dds_info->width && (y + j) < (ssize_t) dds_info->height)
{
code = (bits >> ((4*j+i)*2)) & 0x3;
q->red = ScaleCharToQuantum( colors.r[code] );
q->green = ScaleCharToQuantum( colors.g[code] );
q->blue = ScaleCharToQuantum( colors.b[code] );
/*
Extract alpha value: multiply 0..15 by 17 to get range 0..255
*/
if (j < 2)
alpha = 17U * (unsigned char) ((a0 >> (4*(4*j+i))) & 0xf);
else
alpha = 17U * (unsigned char) ((a1 >> (4*(4*(j-2)+i))) & 0xf);
q->opacity = ScaleCharToQuantum( (unsigned char) (255 - alpha) );
q++;
}
}
}
if (SyncAuthenticPixels(image,exception) == MagickFalse)
return MagickFalse;
}
}
SkipDXTMipmaps(image, dds_info, 16);
return MagickTrue;
}
static MagickBooleanType ReadDXT5(Image *image, DDSInfo *dds_info)
{
DDSColors
colors;
ExceptionInfo
*exception;
ssize_t
j,
y;
MagickSizeType
alpha_bits;
PixelPacket
*q;
register ssize_t
i,
x;
unsigned char
a0,
a1;
size_t
alpha,
bits,
code,
alpha_code;
unsigned short
c0,
c1;
exception=(&image->exception);
for (y = 0; y < (ssize_t) dds_info->height; y += 4)
{
for (x = 0; x < (ssize_t) dds_info->width; x += 4)
{
/* Get 4x4 patch of pixels to write on */
q = QueueAuthenticPixels(image, x, y, Min(4, dds_info->width - x),
Min(4, dds_info->height - y),exception);
if (q == (PixelPacket *) NULL)
return MagickFalse;
/* Read alpha values (8 bytes) */
a0 = (unsigned char) ReadBlobByte(image);
a1 = (unsigned char) ReadBlobByte(image);
alpha_bits = (MagickSizeType)ReadBlobLSBLong(image)
| ((MagickSizeType)ReadBlobLSBShort(image) << 32);
/* Read 8 bytes of data from the image */
c0 = ReadBlobLSBShort(image);
c1 = ReadBlobLSBShort(image);
bits = ReadBlobLSBLong(image);
CalculateColors(c0, c1, &colors, MagickTrue);
/* Write the pixels */
for (j = 0; j < 4; j++)
{
for (i = 0; i < 4; i++)
{
if ((x + i) < (ssize_t) dds_info->width && (y + j) < (ssize_t) dds_info->height)
{
code = (bits >> ((4*j+i)*2)) & 0x3;
q->red = ScaleCharToQuantum( colors.r[code] );
q->green = ScaleCharToQuantum( colors.g[code] );
q->blue = ScaleCharToQuantum( colors.b[code] );
/* Extract alpha value */
alpha_code = (size_t) (alpha_bits >> (3*(4*j+i))) & 0x7;
if (alpha_code == 0)
alpha = a0;
else if (alpha_code == 1)
alpha = a1;
else if (a0 > a1)
alpha = ((8-alpha_code) * a0 + (alpha_code-1) * a1) / 7;
else if (alpha_code == 6)
alpha = alpha_code;
else if (alpha_code == 7)
alpha = 255;
else
alpha = (((6-alpha_code) * a0 + (alpha_code-1) * a1) / 5);
q->opacity = ScaleCharToQuantum( (unsigned char) (255 - alpha) );
q++;
}
}
}
if (SyncAuthenticPixels(image,exception) == MagickFalse)
return MagickFalse;
}
}
SkipDXTMipmaps(image, dds_info, 16);
return MagickTrue;
}
static MagickBooleanType ReadUncompressedRGB(Image *image, DDSInfo *dds_info)
{
ExceptionInfo
*exception;
ssize_t
x, y;
PixelPacket
*q;
exception=(&image->exception);
for (y = 0; y < (ssize_t) dds_info->height; y++)
{
q = QueueAuthenticPixels(image, 0, y, dds_info->width, 1,exception);
if (q == (PixelPacket *) NULL)
return MagickFalse;
for (x = 0; x < (ssize_t) dds_info->width; x++)
{
q->blue = ScaleCharToQuantum( (unsigned char) ReadBlobByte(image) );
q->green = ScaleCharToQuantum( (unsigned char) ReadBlobByte(image) );
q->red = ScaleCharToQuantum( (unsigned char) ReadBlobByte(image) );
if (dds_info->pixelformat.rgb_bitcount == 32)
(void) ReadBlobByte(image);
q++;
}
if (SyncAuthenticPixels(image,exception) == MagickFalse)
return MagickFalse;
}
SkipRGBMipmaps(image, dds_info, 3);
return MagickTrue;
}
static MagickBooleanType ReadUncompressedRGBA(Image *image, DDSInfo *dds_info)
{
ExceptionInfo
*exception;
ssize_t
x, y;
PixelPacket
*q;
exception=(&image->exception);
for (y = 0; y < (ssize_t) dds_info->height; y++)
{
q = QueueAuthenticPixels(image, 0, y, dds_info->width, 1,exception);
if (q == (PixelPacket *) NULL)
return MagickFalse;
for (x = 0; x < (ssize_t) dds_info->width; x++)
{
q->blue = ScaleCharToQuantum( (unsigned char) ReadBlobByte(image) );
q->green = ScaleCharToQuantum( (unsigned char) ReadBlobByte(image) );
q->red = ScaleCharToQuantum( (unsigned char) ReadBlobByte(image) );
q->opacity = ScaleCharToQuantum( (unsigned char) (255 - ReadBlobByte(image)) );
q++;
}
if (SyncAuthenticPixels(image,exception) == MagickFalse)
return MagickFalse;
}
SkipRGBMipmaps(image, dds_info, 4);
return MagickTrue;
}
/*
Skip the mipmap images for compressed (DXTn) dds files
*/
static void SkipDXTMipmaps(Image *image, DDSInfo *dds_info, int texel_size)
{
register ssize_t
i;
MagickOffsetType
offset;
size_t
h,
w;
/*
Only skip mipmaps for textures and cube maps
*/
if (dds_info->ddscaps1 & DDSCAPS_MIPMAP
&& (dds_info->ddscaps1 & DDSCAPS_TEXTURE
|| dds_info->ddscaps2 & DDSCAPS2_CUBEMAP))
{
w = DIV2(dds_info->width);
h = DIV2(dds_info->height);
/*
Mipmapcount includes the main image, so start from one
*/
for (i = 1; (i < (ssize_t) dds_info->mipmapcount) && w && h; i++)
{
offset = (MagickOffsetType) ((w + 3) / 4) * ((h + 3) / 4) * texel_size;
(void) SeekBlob(image, offset, SEEK_CUR);
w = DIV2(w);
h = DIV2(h);
}
}
}
/*
Skip the mipmap images for uncompressed (RGB or RGBA) dds files
*/
static void SkipRGBMipmaps(Image *image, DDSInfo *dds_info, int pixel_size)
{
MagickOffsetType
offset;
register ssize_t
i;
size_t
h,
w;
/*
Only skip mipmaps for textures and cube maps
*/
if (dds_info->ddscaps1 & DDSCAPS_MIPMAP
&& (dds_info->ddscaps1 & DDSCAPS_TEXTURE
|| dds_info->ddscaps2 & DDSCAPS2_CUBEMAP))
{
w = DIV2(dds_info->width);
h = DIV2(dds_info->height);
/*
Mipmapcount includes the main image, so start from one
*/
for (i=1; (i < (ssize_t) dds_info->mipmapcount) && w && h; i++)
{
offset = (MagickOffsetType) w * h * pixel_size;
(void) SeekBlob(image, offset, SEEK_CUR);
w = DIV2(w);
h = DIV2(h);
}
}
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% I s D D S %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% IsDDS() returns MagickTrue if the image format type, identified by the
% magick string, is DDS.
%
% The format of the IsDDS method is:
%
% MagickBooleanType IsDDS(const unsigned char *magick,const size_t length)
%
% A description of each parameter follows:
%
% o magick: compare image format pattern against these bytes.
%
% o length: Specifies the length of the magick string.
%
*/
static MagickBooleanType IsDDS(const unsigned char *magick,const size_t length)
{
if (length < 4)
return(MagickFalse);
if (LocaleNCompare((char *) magick,"DDS ", 4) == 0)
return(MagickTrue);
return(MagickFalse);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% R e g i s t e r D D S I m a g e %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% RegisterDDSImage() adds attributes for the DDS image format to
% the list of supported formats. The attributes include the image format
% tag, a method to read and/or write the format, whether the format
% supports the saving of more than one frame to the same file or blob,
% whether the format supports native in-memory I/O, and a brief
% description of the format.
%
% The format of the RegisterDDSImage method is:
%
% RegisterDDSImage(void)
%
*/
ModuleExport size_t RegisterDDSImage(void)
{
MagickInfo
*entry;
entry = SetMagickInfo("DDS");
entry->decoder = (DecodeImageHandler *) ReadDDSImage;
entry->magick = (IsImageFormatHandler *) IsDDS;
entry->description = ConstantString("Microsoft DirectDraw Surface");
entry->module = ConstantString("DDS");
(void) RegisterMagickInfo(entry);
return(MagickImageCoderSignature);
}
/*
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% %
% %
% U n r e g i s t e r D D S I m a g e %
% %
% %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% UnregisterDDSImage() removes format registrations made by the
% DDS module from the list of supported formats.
%
% The format of the UnregisterDDSImage method is:
%
% UnregisterDDSImage(void)
%
*/
ModuleExport void UnregisterDDSImage(void)
{
(void) UnregisterMagickInfo("DDS");
}