src/media_tools/gpac

/* [<][>][^][v][top][bottom][index][help] */
This source file includes following definitions.
oggpack_writeinit
oggpackB_writeinit
oggpack_writetrunc
oggpackB_writetrunc
oggpack_write
oggpackB_write
oggpack_writealign
oggpackB_writealign
oggpack_writecopy_helper
oggpack_writecopy
oggpackB_writecopy
oggpack_reset
oggpackB_reset
oggpack_writeclear
oggpackB_writeclear
oggpack_readinit
oggpackB_readinit
oggpack_look
oggpackB_look
oggpack_look1
oggpackB_look1
oggpack_adv
oggpackB_adv
oggpack_adv1
oggpackB_adv1
oggpack_read
oggpackB_read
oggpack_read1
oggpackB_read1
oggpack_bytes
oggpack_bits
oggpackB_bytes
oggpackB_bits
oggpack_get_buffer
oggpackB_get_buffer
ogg_page_version
ogg_page_continued
ogg_page_bos
ogg_page_eos
ogg_page_granulepos
ogg_page_serialno
ogg_page_pageno
ogg_page_packets
_ogg_crc_entry
ogg_stream_init
ogg_stream_clear
ogg_stream_destroy
_os_body_expand
_os_lacing_expand
ogg_page_checksum_set
ogg_stream_packetin
ogg_stream_flush
ogg_stream_pageout
ogg_stream_eos
ogg_sync_init
ogg_sync_clear
ogg_sync_destroy
ogg_sync_buffer
ogg_sync_wrote
ogg_sync_pageseek
ogg_sync_pageout
ogg_stream_pagein
ogg_sync_reset
ogg_stream_reset
ogg_stream_reset_serialno
_packetout
ogg_stream_packetout
ogg_stream_packetpeek
ogg_packet_clear


/********************************************************************
 *                                                                  *
 * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE.   *
 * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS     *
 * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
 * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING.       *
 *                                                                  *
 * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2002             *
 * by the Xiph.Org Foundation http://www.xiph.org/                  *
 *                                                                  *
 ********************************************************************

 function: code raw [Vorbis] packets into framed OggSquish stream and
           decode Ogg streams back into raw packets

 note: The CRC code is directly derived from public domain code by
 Ross Williams (ross@guest.adelaide.edu.au).  See docs/framing.html
 for details.

 ********************************************************************/


#include <gpac/internal/ogg.h>

#ifndef GPAC_DISABLE_OGG

#define BUFFER_INCREMENT 256

static u32 mask[]=
{       0x00000000,0x00000001,0x00000003,0x00000007,0x0000000f,
        0x0000001f,0x0000003f,0x0000007f,0x000000ff,0x000001ff,
        0x000003ff,0x000007ff,0x00000fff,0x00001fff,0x00003fff,
        0x00007fff,0x0000ffff,0x0001ffff,0x0003ffff,0x0007ffff,
        0x000fffff,0x001fffff,0x003fffff,0x007fffff,0x00ffffff,
        0x01ffffff,0x03ffffff,0x07ffffff,0x0fffffff,0x1fffffff,
        0x3fffffff,0x7fffffff,0xffffffff
};

static u32 mask8B[]=
{0x00,0x80,0xc0,0xe0,0xf0,0xf8,0xfc,0xfe,0xff};

void oggpack_writeinit(oggpack_buffer *b) {
        memset(b,0,sizeof(*b));
        b->ptr = b->buffer = (unsigned char *)gf_malloc(BUFFER_INCREMENT);
        b->buffer[0]='\0';
        b->storage=BUFFER_INCREMENT;
}

void oggpackB_writeinit(oggpack_buffer *b) {
        oggpack_writeinit(b);
}

void oggpack_writetrunc(oggpack_buffer *b,s32 bits) {
        s32 bytes=bits>>3;
        bits-=bytes*8;
        b->ptr=b->buffer+bytes;
        b->endbit=bits;
        b->endbyte=bytes;
        *b->ptr&=mask[bits];
}

void oggpackB_writetrunc(oggpack_buffer *b,s32 bits) {
        s32 bytes=bits>>3;
        bits-=bytes*8;
        b->ptr=b->buffer+bytes;
        b->endbit=bits;
        b->endbyte=bytes;
        *b->ptr&=mask8B[bits];
}

/* Takes only up to 32 bits. */
void oggpack_write(oggpack_buffer *b,u32 value,s32 bits) {
        if(b->endbyte+4>=b->storage) {
                b->buffer = (unsigned char *)gf_realloc(b->buffer,b->storage+BUFFER_INCREMENT);
                b->storage+=BUFFER_INCREMENT;
                b->ptr=b->buffer+b->endbyte;
        }

        value&=mask[bits];
        bits+=b->endbit;

        b->ptr[0]|=value<<b->endbit;

        if(bits>=8) {
                b->ptr[1]=value>>(8-b->endbit);
                if(bits>=16) {
                        b->ptr[2]=value>>(16-b->endbit);
                        if(bits>=24) {
                                b->ptr[3]=value>>(24-b->endbit);
                                if(bits>=32) {
                                        if(b->endbit)
                                                b->ptr[4]=value>>(32-b->endbit);
                                        else
                                                b->ptr[4]=0;
                                }
                        }
                }
        }

        b->endbyte+=bits/8;
        b->ptr+=bits/8;
        b->endbit=bits&7;
}

/* Takes only up to 32 bits. */
void oggpackB_write(oggpack_buffer *b,u32 value,s32 bits) {
        if(b->endbyte+4>=b->storage) {
                b->buffer = (unsigned char *)gf_realloc(b->buffer,b->storage+BUFFER_INCREMENT);
                b->storage+=BUFFER_INCREMENT;
                b->ptr=b->buffer+b->endbyte;
        }

        value=(value&mask[bits])<<(32-bits);
        bits+=b->endbit;

        b->ptr[0]|=value>>(24+b->endbit);

        if(bits>=8) {
                b->ptr[1]=value>>(16+b->endbit);
                if(bits>=16) {
                        b->ptr[2]=value>>(8+b->endbit);
                        if(bits>=24) {
                                b->ptr[3]=value>>(b->endbit);
                                if(bits>=32) {
                                        if(b->endbit)
                                                b->ptr[4]=value<<(8-b->endbit);
                                        else
                                                b->ptr[4]=0;
                                }
                        }
                }
        }

        b->endbyte+=bits/8;
        b->ptr+=bits/8;
        b->endbit=bits&7;
}

void oggpack_writealign(oggpack_buffer *b) {
        s32 bits=8-b->endbit;
        if(bits<8)
                oggpack_write(b,0,bits);
}

void oggpackB_writealign(oggpack_buffer *b) {
        s32 bits=8-b->endbit;
        if(bits<8)
                oggpackB_write(b,0,bits);
}

static void oggpack_writecopy_helper(oggpack_buffer *b,
                                     void *source,
                                     s32 bits,
                                     void (*w)(oggpack_buffer *,
                                             u32,
                                             s32),
                                     s32 msb) {
        unsigned char *ptr=(unsigned char *)source;

        s32 bytes=bits/8;
        bits-=bytes*8;

        if(b->endbit) {
                s32 i;
                /* unaligned copy.  Do it the hard way. */
                for(i=0; i<bytes; i++)
                        w(b,(u32)(ptr[i]),8);
        } else {
                /* aligned block copy */
                if(b->endbyte+bytes+1>=b->storage) {
                        b->storage=b->endbyte+bytes+BUFFER_INCREMENT;
                        b->buffer = (unsigned char *)gf_realloc(b->buffer,b->storage);
                        b->ptr=b->buffer+b->endbyte;
                }

                memmove(b->ptr,source,bytes);
                b->ptr+=bytes;
                b->buffer+=bytes;
                *b->ptr=0;

        }
        if(bits) {
                if(msb)
                        w(b,(u32)(ptr[bytes]>>(8-bits)),bits);
                else
                        w(b,(u32)(ptr[bytes]),bits);
        }
}

void oggpack_writecopy(oggpack_buffer *b,void *source,s32 bits) {
        oggpack_writecopy_helper(b,source,bits,oggpack_write,0);
}

void oggpackB_writecopy(oggpack_buffer *b,void *source,s32 bits) {
        oggpack_writecopy_helper(b,source,bits,oggpackB_write,1);
}

void oggpack_reset(oggpack_buffer *b) {
        b->ptr=b->buffer;
        b->buffer[0]=0;
        b->endbit=b->endbyte=0;
}

void oggpackB_reset(oggpack_buffer *b) {
        oggpack_reset(b);
}

void oggpack_writeclear(oggpack_buffer *b) {
        gf_free(b->buffer);
        memset(b,0,sizeof(*b));
}

void oggpackB_writeclear(oggpack_buffer *b) {
        oggpack_writeclear(b);
}

void oggpack_readinit(oggpack_buffer *b,unsigned char *buf,s32 bytes) {
        memset(b,0,sizeof(*b));
        b->buffer=b->ptr=buf;
        b->storage=bytes;
}

void oggpackB_readinit(oggpack_buffer *b,unsigned char *buf,s32 bytes) {
        oggpack_readinit(b,buf,bytes);
}

/* Read in bits without advancing the bitptr; bits <= 32 */
s32 oggpack_look(oggpack_buffer *b,s32 bits) {
        u32 ret;
        u32 m=mask[bits];

        bits+=b->endbit;

        if(b->endbyte+4>=b->storage) {
                /* not the main path */
                if(b->endbyte*8+bits>b->storage*8)return(-1);
        }

        ret=b->ptr[0]>>b->endbit;
        if(bits>8) {
                ret|=b->ptr[1]<<(8-b->endbit);
                if(bits>16) {
                        ret|=b->ptr[2]<<(16-b->endbit);
                        if(bits>24) {
                                ret|=b->ptr[3]<<(24-b->endbit);
                                if(bits>32 && b->endbit)
                                        ret|=b->ptr[4]<<(32-b->endbit);
                        }
                }
        }
        return(m&ret);
}

/* Read in bits without advancing the bitptr; bits <= 32 */
s32 oggpackB_look(oggpack_buffer *b,s32 bits) {
        u32 ret;
        s32 m=32-bits;

        bits+=b->endbit;

        if(b->endbyte+4>=b->storage) {
                /* not the main path */
                if(b->endbyte*8+bits>b->storage*8)return(-1);
        }

        ret=b->ptr[0]<<(24+b->endbit);
        if(bits>8) {
                ret|=b->ptr[1]<<(16+b->endbit);
                if(bits>16) {
                        ret|=b->ptr[2]<<(8+b->endbit);
                        if(bits>24) {
                                ret|=b->ptr[3]<<(b->endbit);
                                if(bits>32 && b->endbit)
                                        ret|=b->ptr[4]>>(8-b->endbit);
                        }
                }
        }
        return (ret>>(m>>1))>>((m+1)>>1);
}

s32 oggpack_look1(oggpack_buffer *b) {
        if(b->endbyte>=b->storage)return(-1);
        return((b->ptr[0]>>b->endbit)&1);
}

s32 oggpackB_look1(oggpack_buffer *b) {
        if(b->endbyte>=b->storage)return(-1);
        return((b->ptr[0]>>(7-b->endbit))&1);
}

void oggpack_adv(oggpack_buffer *b,s32 bits) {
        bits+=b->endbit;
        b->ptr+=bits/8;
        b->endbyte+=bits/8;
        b->endbit=bits&7;
}

void oggpackB_adv(oggpack_buffer *b,s32 bits) {
        oggpack_adv(b,bits);
}

void oggpack_adv1(oggpack_buffer *b) {
        if(++(b->endbit)>7) {
                b->endbit=0;
                b->ptr++;
                b->endbyte++;
        }
}

void oggpackB_adv1(oggpack_buffer *b) {
        oggpack_adv1(b);
}

/* bits <= 32 */
s32 oggpack_read(oggpack_buffer *b,s32 bits) {
        u32 ret;
        u32 m=mask[bits];

        bits+=b->endbit;

        if(b->endbyte+4>=b->storage) {
                /* not the main path */
                ret=(u32) (-1);
                if(b->endbyte*8+bits>b->storage*8)goto overflow;
        }

        ret=b->ptr[0]>>b->endbit;
        if(bits>8) {
                ret|=b->ptr[1]<<(8-b->endbit);
                if(bits>16) {
                        ret|=b->ptr[2]<<(16-b->endbit);
                        if(bits>24) {
                                ret|=b->ptr[3]<<(24-b->endbit);
                                if(bits>32 && b->endbit) {
                                        ret|=b->ptr[4]<<(32-b->endbit);
                                }
                        }
                }
        }
        ret&=m;

overflow:

        b->ptr+=bits/8;
        b->endbyte+=bits/8;
        b->endbit=bits&7;
        return(ret);
}

/* bits <= 32 */
s32 oggpackB_read(oggpack_buffer *b,s32 bits) {
        u32 ret;
        s32 m=32-bits;

        bits+=b->endbit;

        if(b->endbyte+4>=b->storage) {
                /* not the main path */
                ret=(u32) (-1);
                if(b->endbyte*8+bits>b->storage*8)goto overflow;
        }

        ret=b->ptr[0]<<(24+b->endbit);
        if(bits>8) {
                ret|=b->ptr[1]<<(16+b->endbit);
                if(bits>16) {
                        ret|=b->ptr[2]<<(8+b->endbit);
                        if(bits>24) {
                                ret|=b->ptr[3]<<(b->endbit);
                                if(bits>32 && b->endbit)
                                        ret|=b->ptr[4]>>(8-b->endbit);
                        }
                }
        }
        ret=(ret>>(m>>1))>>((m+1)>>1);

overflow:

        b->ptr+=bits/8;
        b->endbyte+=bits/8;
        b->endbit=bits&7;
        return(ret);
}

s32 oggpack_read1(oggpack_buffer *b) {
        u32 ret;

        if(b->endbyte>=b->storage) {
                /* not the main path */
                ret=(u32) (-1);
                goto overflow;
        }

        ret=(b->ptr[0]>>b->endbit)&1;

overflow:

        b->endbit++;
        if(b->endbit>7) {
                b->endbit=0;
                b->ptr++;
                b->endbyte++;
        }
        return(ret);
}

s32 oggpackB_read1(oggpack_buffer *b) {
        u32 ret;

        if(b->endbyte>=b->storage) {
                /* not the main path */
                ret=(u32) (-1);
                goto overflow;
        }

        ret=(b->ptr[0]>>(7-b->endbit))&1;

overflow:

        b->endbit++;
        if(b->endbit>7) {
                b->endbit=0;
                b->ptr++;
                b->endbyte++;
        }
        return(ret);
}

s32 oggpack_bytes(oggpack_buffer *b) {
        return(b->endbyte+(b->endbit+7)/8);
}

s32 oggpack_bits(oggpack_buffer *b) {
        return(b->endbyte*8+b->endbit);
}

s32 oggpackB_bytes(oggpack_buffer *b) {
        return oggpack_bytes(b);
}

s32 oggpackB_bits(oggpack_buffer *b) {
        return oggpack_bits(b);
}

unsigned char *oggpack_get_buffer(oggpack_buffer *b) {
        return(b->buffer);
}

unsigned char *oggpackB_get_buffer(oggpack_buffer *b) {
        return oggpack_get_buffer(b);
}


#undef BUFFER_INCREMENT

/* A complete description of Ogg framing exists in docs/framing.html */

s32 ogg_page_version(ogg_page *og) {
        return((s32)(og->header[4]));
}

s32 ogg_page_continued(ogg_page *og) {
        return((s32)(og->header[5]&0x01));
}

s32 ogg_page_bos(ogg_page *og) {
        return((s32)(og->header[5]&0x02));
}

s32 ogg_page_eos(ogg_page *og) {
        return((s32)(og->header[5]&0x04));
}

s64 ogg_page_granulepos(ogg_page *og) {
        unsigned char *page=og->header;
        s64 granulepos=page[13]&(0xff);
        granulepos= (granulepos<<8)|(page[12]&0xff);
        granulepos= (granulepos<<8)|(page[11]&0xff);
        granulepos= (granulepos<<8)|(page[10]&0xff);
        granulepos= (granulepos<<8)|(page[9]&0xff);
        granulepos= (granulepos<<8)|(page[8]&0xff);
        granulepos= (granulepos<<8)|(page[7]&0xff);
        granulepos= (granulepos<<8)|(page[6]&0xff);
        return(granulepos);
}

s32 ogg_page_serialno(ogg_page *og) {
        return(og->header[14] |
               (og->header[15]<<8) |
               (og->header[16]<<16) |
               (og->header[17]<<24));
}

s32 ogg_page_pageno(ogg_page *og) {
        return(og->header[18] |
               (og->header[19]<<8) |
               (og->header[20]<<16) |
               (og->header[21]<<24));
}



/* returns the number of packets that are completed on this page (if
   the leading packet is begun on a previous page, but ends on this
   page, it's counted */

/* NOTE:
If a page consists of a packet begun on a previous page, and a new
packet begun (but not completed) on this page, the return will be:
  ogg_page_packets(page)   ==1,
  ogg_page_continued(page) !=0

If a page happens to be a single packet that was begun on a
previous page, and spans to the next page (in the case of a three or
more page packet), the return will be:
  ogg_page_packets(page)   ==0,
  ogg_page_continued(page) !=0
*/

s32 ogg_page_packets(ogg_page *og) {
        s32 i,n=og->header[26],count=0;
        for(i=0; i<n; i++)
                if(og->header[27+i]<255)count++;
        return(count);
}


#if 0
/* helper to initialize lookup for direct-table CRC (illustrative; we
   use the static init below) */

static u32 _ogg_crc_entry(u32 index) {
        s32           i;
        u32 r;

        r = index << 24;
        for (i=0; i<8; i++)
                if (r & 0x80000000UL)
                        r = (r << 1) ^ 0x04c11db7; /* The same as the ethernet generator
                                    polynomial, although we use an
                                    unreflected alg and an init/final
                                    of 0, not 0xffffffff */
                else
                        r<<=1;
        return (r & 0xffffffffUL);
}
#endif

static u32 crc_lookup[256]= {
        0x00000000,0x04c11db7,0x09823b6e,0x0d4326d9,
        0x130476dc,0x17c56b6b,0x1a864db2,0x1e475005,
        0x2608edb8,0x22c9f00f,0x2f8ad6d6,0x2b4bcb61,
        0x350c9b64,0x31cd86d3,0x3c8ea00a,0x384fbdbd,
        0x4c11db70,0x48d0c6c7,0x4593e01e,0x4152fda9,
        0x5f15adac,0x5bd4b01b,0x569796c2,0x52568b75,
        0x6a1936c8,0x6ed82b7f,0x639b0da6,0x675a1011,
        0x791d4014,0x7ddc5da3,0x709f7b7a,0x745e66cd,
        0x9823b6e0,0x9ce2ab57,0x91a18d8e,0x95609039,
        0x8b27c03c,0x8fe6dd8b,0x82a5fb52,0x8664e6e5,
        0xbe2b5b58,0xbaea46ef,0xb7a96036,0xb3687d81,
        0xad2f2d84,0xa9ee3033,0xa4ad16ea,0xa06c0b5d,
        0xd4326d90,0xd0f37027,0xddb056fe,0xd9714b49,
        0xc7361b4c,0xc3f706fb,0xceb42022,0xca753d95,
        0xf23a8028,0xf6fb9d9f,0xfbb8bb46,0xff79a6f1,
        0xe13ef6f4,0xe5ffeb43,0xe8bccd9a,0xec7dd02d,
        0x34867077,0x30476dc0,0x3d044b19,0x39c556ae,
        0x278206ab,0x23431b1c,0x2e003dc5,0x2ac12072,
        0x128e9dcf,0x164f8078,0x1b0ca6a1,0x1fcdbb16,
        0x018aeb13,0x054bf6a4,0x0808d07d,0x0cc9cdca,
        0x7897ab07,0x7c56b6b0,0x71159069,0x75d48dde,
        0x6b93dddb,0x6f52c06c,0x6211e6b5,0x66d0fb02,
        0x5e9f46bf,0x5a5e5b08,0x571d7dd1,0x53dc6066,
        0x4d9b3063,0x495a2dd4,0x44190b0d,0x40d816ba,
        0xaca5c697,0xa864db20,0xa527fdf9,0xa1e6e04e,
        0xbfa1b04b,0xbb60adfc,0xb6238b25,0xb2e29692,
        0x8aad2b2f,0x8e6c3698,0x832f1041,0x87ee0df6,
        0x99a95df3,0x9d684044,0x902b669d,0x94ea7b2a,
        0xe0b41de7,0xe4750050,0xe9362689,0xedf73b3e,
        0xf3b06b3b,0xf771768c,0xfa325055,0xfef34de2,
        0xc6bcf05f,0xc27dede8,0xcf3ecb31,0xcbffd686,
        0xd5b88683,0xd1799b34,0xdc3abded,0xd8fba05a,
        0x690ce0ee,0x6dcdfd59,0x608edb80,0x644fc637,
        0x7a089632,0x7ec98b85,0x738aad5c,0x774bb0eb,
        0x4f040d56,0x4bc510e1,0x46863638,0x42472b8f,
        0x5c007b8a,0x58c1663d,0x558240e4,0x51435d53,
        0x251d3b9e,0x21dc2629,0x2c9f00f0,0x285e1d47,
        0x36194d42,0x32d850f5,0x3f9b762c,0x3b5a6b9b,
        0x0315d626,0x07d4cb91,0x0a97ed48,0x0e56f0ff,
        0x1011a0fa,0x14d0bd4d,0x19939b94,0x1d528623,
        0xf12f560e,0xf5ee4bb9,0xf8ad6d60,0xfc6c70d7,
        0xe22b20d2,0xe6ea3d65,0xeba91bbc,0xef68060b,
        0xd727bbb6,0xd3e6a601,0xdea580d8,0xda649d6f,
        0xc423cd6a,0xc0e2d0dd,0xcda1f604,0xc960ebb3,
        0xbd3e8d7e,0xb9ff90c9,0xb4bcb610,0xb07daba7,
        0xae3afba2,0xaafbe615,0xa7b8c0cc,0xa379dd7b,
        0x9b3660c6,0x9ff77d71,0x92b45ba8,0x9675461f,
        0x8832161a,0x8cf30bad,0x81b02d74,0x857130c3,
        0x5d8a9099,0x594b8d2e,0x5408abf7,0x50c9b640,
        0x4e8ee645,0x4a4ffbf2,0x470cdd2b,0x43cdc09c,
        0x7b827d21,0x7f436096,0x7200464f,0x76c15bf8,
        0x68860bfd,0x6c47164a,0x61043093,0x65c52d24,
        0x119b4be9,0x155a565e,0x18197087,0x1cd86d30,
        0x029f3d35,0x065e2082,0x0b1d065b,0x0fdc1bec,
        0x3793a651,0x3352bbe6,0x3e119d3f,0x3ad08088,
        0x2497d08d,0x2056cd3a,0x2d15ebe3,0x29d4f654,
        0xc5a92679,0xc1683bce,0xcc2b1d17,0xc8ea00a0,
        0xd6ad50a5,0xd26c4d12,0xdf2f6bcb,0xdbee767c,
        0xe3a1cbc1,0xe760d676,0xea23f0af,0xeee2ed18,
        0xf0a5bd1d,0xf464a0aa,0xf9278673,0xfde69bc4,
        0x89b8fd09,0x8d79e0be,0x803ac667,0x84fbdbd0,
        0x9abc8bd5,0x9e7d9662,0x933eb0bb,0x97ffad0c,
        0xafb010b1,0xab710d06,0xa6322bdf,0xa2f33668,
        0xbcb4666d,0xb8757bda,0xb5365d03,0xb1f740b4
};

/* init the encode/decode logical stream state */

s32 ogg_stream_init(ogg_stream_state *os,s32 serialno) {
        if(os) {
                memset(os,0,sizeof(*os));
                os->body_storage=16*1024;
                os->body_data = (unsigned char *)gf_malloc(os->body_storage*sizeof(*os->body_data));

                os->lacing_storage=1024;
                os->lacing_vals=(s32 *)gf_malloc(os->lacing_storage*sizeof(*os->lacing_vals));
                os->granule_vals=(s64*)gf_malloc(os->lacing_storage*sizeof(*os->granule_vals));

                os->serialno=serialno;

                return(0);
        }
        return(-1);
}

/* _clear does not free os, only the non-flat storage within */
s32 ogg_stream_clear(ogg_stream_state *os) {
        if(os) {
                if(os->body_data)gf_free(os->body_data);
                if(os->lacing_vals)gf_free(os->lacing_vals);
                if(os->granule_vals)gf_free(os->granule_vals);

                memset(os,0,sizeof(*os));
        }
        return(0);
}

s32 ogg_stream_destroy(ogg_stream_state *os) {
        if(os) {
                ogg_stream_clear(os);
                gf_free(os);
        }
        return(0);
}

/* Helpers for ogg_stream_encode; this keeps the structure and
   what's happening fairly clear */

static void _os_body_expand(ogg_stream_state *os,s32 needed) {
        if(os->body_storage<=os->body_fill+needed) {
                os->body_storage+=(needed+1024);
                os->body_data = (unsigned char *)gf_realloc(os->body_data,os->body_storage*sizeof(*os->body_data));
        }
}

static void _os_lacing_expand(ogg_stream_state *os,s32 needed) {
        if(os->lacing_storage<=os->lacing_fill+needed) {
                os->lacing_storage+=(needed+32);
                os->lacing_vals=(s32*)gf_realloc(os->lacing_vals,os->lacing_storage*sizeof(*os->lacing_vals));
                os->granule_vals=(s64*)gf_realloc(os->granule_vals,os->lacing_storage*sizeof(*os->granule_vals));
        }
}

/* checksum the page */
/* Direct table CRC; note that this will be faster in the future if we
   perform the checksum silmultaneously with other copies */

void ogg_page_checksum_set(ogg_page *og) {
        if(og) {
                u32 crc_reg=0;
                s32 i;

                /* safety; needed for API behavior, but not framing code */
                og->header[22]=0;
                og->header[23]=0;
                og->header[24]=0;
                og->header[25]=0;

                for(i=0; i<og->header_len; i++)
                        crc_reg=(crc_reg<<8)^crc_lookup[((crc_reg >> 24)&0xff)^og->header[i]];
                for(i=0; i<og->body_len; i++)
                        crc_reg=(crc_reg<<8)^crc_lookup[((crc_reg >> 24)&0xff)^og->body[i]];

                og->header[22]=crc_reg&0xff;
                og->header[23]=(crc_reg>>8)&0xff;
                og->header[24]=(crc_reg>>16)&0xff;
                og->header[25]=(crc_reg>>24)&0xff;
        }
}

/* submit data to the internal buffer of the framing engine */
s32 ogg_stream_packetin(ogg_stream_state *os,ogg_packet *op) {
        s32 lacing_vals=op->bytes/255+1,i;

        if(os->body_returned) {
                /* advance packet data according to the body_returned pointer. We
                   had to keep it around to return a pointer into the buffer last
                   call */

                os->body_fill-=os->body_returned;
                if(os->body_fill)
                        memmove(os->body_data,os->body_data+os->body_returned,
                                os->body_fill);
                os->body_returned=0;
        }

        /* make sure we have the buffer storage */
        _os_body_expand(os,op->bytes);
        _os_lacing_expand(os,lacing_vals);

        /* Copy in the submitted packet.  Yes, the copy is a waste; this is
           the liability of overly clean abstraction for the time being.  It
           will actually be fairly easy to eliminate the extra copy in the
           future */

        memcpy(os->body_data+os->body_fill,op->packet,op->bytes);
        os->body_fill+=op->bytes;

        /* Store lacing vals for this packet */
        for(i=0; i<lacing_vals-1; i++) {
                os->lacing_vals[os->lacing_fill+i]=255;
                os->granule_vals[os->lacing_fill+i]=os->granulepos;
        }
        os->lacing_vals[os->lacing_fill+i]=(op->bytes)%255;
        os->granulepos=os->granule_vals[os->lacing_fill+i]=op->granulepos;

        /* flag the first segment as the beginning of the packet */
        os->lacing_vals[os->lacing_fill]|= 0x100;

        os->lacing_fill+=lacing_vals;

        /* for the sake of completeness */
        os->packetno++;

        if(op->e_o_s)os->e_o_s=1;

        return(0);
}

/* This will flush remaining packets into a page (returning nonzero),
   even if there is not enough data to trigger a flush normally
   (undersized page). If there are no packets or partial packets to
   flush, ogg_stream_flush returns 0.  Note that ogg_stream_flush will
   try to flush a normal sized page like ogg_stream_pageout; a call to
   ogg_stream_flush does not guarantee that all packets have flushed.
   Only a return value of 0 from ogg_stream_flush indicates all packet
   data is flushed into pages.

   since ogg_stream_flush will flush the last page in a stream even if
   it's undersized, you almost certainly want to use ogg_stream_pageout
   (and *not* ogg_stream_flush) unless you specifically need to flush
   an page regardless of size in the middle of a stream. */

s32 ogg_stream_flush(ogg_stream_state *os,ogg_page *og) {
        s32 i;
        s32 vals=0;
        s32 maxvals=(os->lacing_fill>255?255:os->lacing_fill);
        s32 bytes=0;
        s32 acc=0;
        s64 granule_pos=os->granule_vals[0];

        if(maxvals==0)return(0);

        /* construct a page */
        /* decide how many segments to include */

        /* If this is the initial header case, the first page must only include
           the initial header packet */
        if(os->b_o_s==0) { /* 'initial header page' case */
                granule_pos=0;
                for(vals=0; vals<maxvals; vals++) {
                        if((os->lacing_vals[vals]&0x0ff)<255) {
                                vals++;
                                break;
                        }
                }
        } else {
                for(vals=0; vals<maxvals; vals++) {
                        if(acc>4096)break;
                        acc+=os->lacing_vals[vals]&0x0ff;
                        granule_pos=os->granule_vals[vals];
                }
        }

        /* construct the header in temp storage */
        memcpy(os->header,"OggS",4);

        /* stream structure version */
        os->header[4]=0x00;

        /* continued packet flag? */
        os->header[5]=0x00;
        if((os->lacing_vals[0]&0x100)==0)os->header[5]|=0x01;
        /* first page flag? */
        if(os->b_o_s==0)os->header[5]|=0x02;
        /* last page flag? */
        if(os->e_o_s && os->lacing_fill==vals)os->header[5]|=0x04;
        os->b_o_s=1;

        /* 64 bits of PCM position */
        for(i=6; i<14; i++) {
                os->header[i]=(u8) (granule_pos&0xff);
                granule_pos>>=8;
        }

        /* 32 bits of stream serial number */
        {
                s32 serialno=os->serialno;
                for(i=14; i<18; i++) {
                        os->header[i]=(serialno&0xff);
                        serialno>>=8;
                }
        }

        /* 32 bits of page counter (we have both counter and page header
           because this val can roll over) */
        if(os->pageno==-1)os->pageno=0; /* because someone called
                                     stream_reset; this would be a
                                     strange thing to do in an
                                     encode stream, but it has
                                     plausible uses */
        {
                s32 pageno=os->pageno++;
                for(i=18; i<22; i++) {
                        os->header[i]=(pageno&0xff);
                        pageno>>=8;
                }
        }

        /* zero for computation; filled in later */
        os->header[22]=0;
        os->header[23]=0;
        os->header[24]=0;
        os->header[25]=0;

        /* segment table */
        os->header[26]=vals&0xff;
        for(i=0; i<vals; i++)
                bytes+=os->header[i+27]=(os->lacing_vals[i]&0xff);

        /* set pointers in the ogg_page struct */
        og->header=os->header;
        og->header_len=os->header_fill=vals+27;
        og->body=os->body_data+os->body_returned;
        og->body_len=bytes;

        /* advance the lacing data and set the body_returned pointer */

        os->lacing_fill-=vals;
        memmove(os->lacing_vals,os->lacing_vals+vals,os->lacing_fill*sizeof(*os->lacing_vals));
        memmove(os->granule_vals,os->granule_vals+vals,os->lacing_fill*sizeof(*os->granule_vals));
        os->body_returned+=bytes;

        /* calculate the checksum */

        ogg_page_checksum_set(og);

        /* done */
        return(1);
}


/* This constructs pages from buffered packet segments.  The pointers
returned are to static buffers; do not free. The returned buffers are
good only until the next call (using the same ogg_stream_state) */

s32 ogg_stream_pageout(ogg_stream_state *os, ogg_page *og) {

        if((os->e_o_s&&os->lacing_fill) ||          /* 'were done, now flush' case */
                os->body_fill-os->body_returned > 4096 ||/* 'page nominal size' case */
                os->lacing_fill>=255 ||                  /* 'segment table full' case */
                (os->lacing_fill&&!os->b_o_s)) {         /* 'initial header page' case */

                return(ogg_stream_flush(os,og));
        }

        /* not enough data to construct a page and not end of stream */
        return(0);
}

s32 ogg_stream_eos(ogg_stream_state *os) {
        return os->e_o_s;
}

/* DECODING PRIMITIVES: packet streaming layer **********************/

/* This has two layers to place more of the multi-serialno and paging
   control in the application's hands.  First, we expose a data buffer
   using ogg_sync_buffer().  The app either copies into the
   buffer, or passes it directly to read(), etc.  We then call
   ogg_sync_wrote() to tell how many bytes we just added.

   Pages are returned (pointers into the buffer in ogg_sync_state)
   by ogg_sync_pageout().  The page is then submitted to
   ogg_stream_pagein() along with the appropriate
   ogg_stream_state* (ie, matching serialno).  We then get raw
   packets out calling ogg_stream_packetout() with a
   ogg_stream_state.  See the 'frame-prog.txt' docs for details and
   example code. */

/* initialize the struct to a known state */
s32 ogg_sync_init(ogg_sync_state *oy) {
        if(oy) {
                memset(oy,0,sizeof(*oy));
        }
        return(0);
}

/* clear non-flat storage within */
s32 ogg_sync_clear(ogg_sync_state *oy) {
        if(oy) {
                if(oy->data)gf_free(oy->data);
                ogg_sync_init(oy);
        }
        return(0);
}

s32 ogg_sync_destroy(ogg_sync_state *oy) {
        if(oy) {
                ogg_sync_clear(oy);
                gf_free(oy);
        }
        return(0);
}

char *ogg_sync_buffer(ogg_sync_state *oy, s32 size) {

        /* first, clear out any space that has been previously returned */
        if(oy->returned) {
                oy->fill-=oy->returned;
                if(oy->fill>0)
                        memmove(oy->data,oy->data+oy->returned,oy->fill);
                oy->returned=0;
        }

        if(size>oy->storage-oy->fill) {
                /* We need to extend the internal buffer */
                s32 newsize=size+oy->fill+4096; /* an extra page to be nice */

                if(oy->data)
                        oy->data = (unsigned char *)gf_realloc(oy->data,newsize);
                else
                        oy->data = (unsigned char *)gf_malloc(newsize);
                oy->storage=newsize;
        }

        /* expose a segment at least as large as requested at the fill mark */
        return((char *)oy->data+oy->fill);
}

s32 ogg_sync_wrote(ogg_sync_state *oy, s32 bytes) {
        if(oy->fill+bytes>oy->storage)return(-1);
        oy->fill+=bytes;
        return(0);
}

/* sync the stream.  This is meant to be useful for finding page
   boundaries.

   return values for this:
  -n) skipped n bytes
   0) page not ready; more data (no bytes skipped)
   n) page synced at current location; page length n bytes

*/

s32 ogg_sync_pageseek(ogg_sync_state *oy,ogg_page *og) {
        unsigned char *page=oy->data+oy->returned;
        unsigned char *next;
        s32 bytes=oy->fill-oy->returned;

        if(oy->headerbytes==0) {
                s32 headerbytes,i;
                if(bytes<27)return(0); /* not enough for a header */

                /* verify capture pattern */
                if(memcmp(page,"OggS",4))goto sync_fail;

                headerbytes=page[26]+27;
                if(bytes<headerbytes)return(0); /* not enough for header + seg table */

                /* count up body length in the segment table */

                for(i=0; i<page[26]; i++)
                        oy->bodybytes+=page[27+i];
                oy->headerbytes=headerbytes;
        }

        if(oy->bodybytes+oy->headerbytes>bytes)return(0);

        /* The whole test page is buffered.  Verify the checksum */
        {
                /* Grab the checksum bytes, set the header field to zero */
                char chksum[4];
                ogg_page log;

                memcpy(chksum,page+22,4);
                memset(page+22,0,4);

                /* set up a temp page struct and recompute the checksum */
                log.header=page;
                log.header_len=oy->headerbytes;
                log.body=page+oy->headerbytes;
                log.body_len=oy->bodybytes;
                ogg_page_checksum_set(&log);

                /* Compare */
                if(memcmp(chksum,page+22,4)) {
                        /* D'oh.  Mismatch! Corrupt page (or miscapture and not a page
                        at all) */
                        /* replace the computed checksum with the one actually read in */
                        memcpy(page+22,chksum,4);

                        /* Bad checksum. Lose sync */
                        goto sync_fail;
                }
        }

        /* yes, have a whole page all ready to go */
        {
                unsigned char *page=oy->data+oy->returned;
                s32 bytes;

                if(og) {
                        og->header=page;
                        og->header_len=oy->headerbytes;
                        og->body=page+oy->headerbytes;
                        og->body_len=oy->bodybytes;
                }

                oy->unsynced=0;
                oy->returned+=(bytes=oy->headerbytes+oy->bodybytes);
                oy->headerbytes=0;
                oy->bodybytes=0;
                return(bytes);
        }

sync_fail:

        oy->headerbytes=0;
        oy->bodybytes=0;

        /* search for possible capture */
        next = (unsigned char *)memchr(page+1,'O',bytes-1);
        if(!next)
                next=oy->data+oy->fill;

        oy->returned = (s32) (next-oy->data);
        return (s32) (-(next-page));
}

/* sync the stream and get a page.  Keep trying until we find a page.
   Supress 'sync errors' after reporting the first.

   return values:
   -1) recapture (hole in data)
    0) need more data
    1) page returned

   Returns pointers into buffered data; invalidated by next call to
   _stream, _clear, _init, or _buffer */

s32 ogg_sync_pageout(ogg_sync_state *oy, ogg_page *og) {

        /* all we need to do is verify a page at the head of the stream
           buffer.  If it doesn't verify, we look for the next potential
           frame */

        while(1) {
                s32 ret=ogg_sync_pageseek(oy,og);
                if(ret>0) {
                        /* have a page */
                        return(1);
                }
                if(ret==0) {
                        /* need more data */
                        return(0);
                }

                /* head did not start a synced page... skipped some bytes */
                if(!oy->unsynced) {
                        oy->unsynced=1;
                        return(-1);
                }

                /* loop. keep looking */

        }
}

/* add the incoming page to the stream state; we decompose the page
   into packet segments here as well. */

s32 ogg_stream_pagein(ogg_stream_state *os, ogg_page *og) {
        unsigned char *header=og->header;
        unsigned char *body=og->body;
        s32           bodysize=og->body_len;
        s32            segptr=0;

        s32 version=ogg_page_version(og);
        s32 continued=ogg_page_continued(og);
        s32 bos=ogg_page_bos(og);
        s32 eos=ogg_page_eos(og);
        s64 granulepos=ogg_page_granulepos(og);
        s32 serialno=ogg_page_serialno(og);
        s32 pageno=ogg_page_pageno(og);
        s32 segments=header[26];

        /* clean up 'returned data' */
        {
                s32 lr=os->lacing_returned;
                s32 br=os->body_returned;

                /* body data */
                if(br) {
                        os->body_fill-=br;
                        if(os->body_fill)
                                memmove(os->body_data,os->body_data+br,os->body_fill);
                        os->body_returned=0;
                }

                if(lr) {
                        /* segment table */
                        if(os->lacing_fill-lr) {
                                memmove(os->lacing_vals,os->lacing_vals+lr,
                                        (os->lacing_fill-lr)*sizeof(*os->lacing_vals));
                                memmove(os->granule_vals,os->granule_vals+lr,
                                        (os->lacing_fill-lr)*sizeof(*os->granule_vals));
                        }
                        os->lacing_fill-=lr;
                        os->lacing_packet-=lr;
                        os->lacing_returned=0;
                }
        }

        /* check the serial number */
        if(serialno!=os->serialno)return(-1);
        if(version>0)return(-1);

        _os_lacing_expand(os,segments+1);

        /* are we in sequence? */
        if(pageno!=os->pageno) {
                s32 i;

                /* unroll previous partial packet (if any) */
                for(i=os->lacing_packet; i<os->lacing_fill; i++)
                        os->body_fill-=os->lacing_vals[i]&0xff;
                os->lacing_fill=os->lacing_packet;

                /* make a note of dropped data in segment table */
                if(os->pageno!=-1) {
                        os->lacing_vals[os->lacing_fill++]=0x400;
                        os->lacing_packet++;
                }

                /* are we a 'continued packet' page?  If so, we'll need to skip
                   some segments */
                if(continued) {
                        bos=0;
                        for(; segptr<segments; segptr++) {
                                s32 val=header[27+segptr];
                                body+=val;
                                bodysize-=val;
                                if(val<255) {
                                        segptr++;
                                        break;
                                }
                        }
                }
        }

        if(bodysize) {
                _os_body_expand(os,bodysize);
                memcpy(os->body_data+os->body_fill,body,bodysize);
                os->body_fill+=bodysize;
        }

        {
                s32 saved=-1;
                while(segptr<segments) {
                        s32 val=header[27+segptr];
                        os->lacing_vals[os->lacing_fill]=val;
                        os->granule_vals[os->lacing_fill]=-1;

                        if(bos) {
                                os->lacing_vals[os->lacing_fill]|=0x100;
                                bos=0;
                        }

                        if(val<255)saved=os->lacing_fill;

                        os->lacing_fill++;
                        segptr++;

                        if(val<255)os->lacing_packet=os->lacing_fill;
                }

                /* set the granulepos on the last granuleval of the last full packet */
                if(saved!=-1) {
                        os->granule_vals[saved]=granulepos;
                }

        }

        if(eos) {
                os->e_o_s=1;
                if(os->lacing_fill>0)
                        os->lacing_vals[os->lacing_fill-1]|=0x200;
        }

        os->pageno=pageno+1;

        return(0);
}

/* clear things to an initial state.  Good to call, eg, before seeking */
s32 ogg_sync_reset(ogg_sync_state *oy) {
        oy->fill=0;
        oy->returned=0;
        oy->unsynced=0;
        oy->headerbytes=0;
        oy->bodybytes=0;
        return(0);
}

s32 ogg_stream_reset(ogg_stream_state *os) {
        os->body_fill=0;
        os->body_returned=0;

        os->lacing_fill=0;
        os->lacing_packet=0;
        os->lacing_returned=0;

        os->header_fill=0;

        os->e_o_s=0;
        os->b_o_s=0;
        os->pageno=-1;
        os->packetno=0;
        os->granulepos=0;

        return(0);
}

s32 ogg_stream_reset_serialno(ogg_stream_state *os,s32 serialno) {
        ogg_stream_reset(os);
        os->serialno=serialno;
        return(0);
}

static s32 _packetout(ogg_stream_state *os,ogg_packet *op,s32 adv) {

        /* The last part of decode. We have the stream broken into packet
           segments.  Now we need to group them into packets (or return the
           out of sync markers) */

        s32 ptr=os->lacing_returned;

        if(os->lacing_packet<=ptr)return(0);

        if(os->lacing_vals[ptr]&0x400) {
                /* we need to tell the codec there's a gap; it might need to
                   handle previous packet dependencies. */
                os->lacing_returned++;
                os->packetno++;
                return(-1);
        }

        if(!op && !adv)return(1); /* just using peek as an inexpensive way
                               to ask if there's a whole packet
                               waiting */

        /* Gather the whole packet. We'll have no holes or a partial packet */
        {
                s32 size=os->lacing_vals[ptr]&0xff;
                s32 bytes=size;
                s32 eos=os->lacing_vals[ptr]&0x200; /* last packet of the stream? */
                s32 bos=os->lacing_vals[ptr]&0x100; /* first packet of the stream? */

                while(size==255) {
                        s32 val=os->lacing_vals[++ptr];
                        size=val&0xff;
                        if(val&0x200)eos=0x200;
                        bytes+=size;
                }

                if(op) {
                        op->e_o_s=eos;
                        op->b_o_s=bos;
                        op->packet=os->body_data+os->body_returned;
                        op->packetno=os->packetno;
                        op->granulepos=os->granule_vals[ptr];
                        op->bytes=bytes;
                }

                if(adv) {
                        os->body_returned+=bytes;
                        os->lacing_returned=ptr+1;
                        os->packetno++;
                }
        }
        return(1);
}

s32 ogg_stream_packetout(ogg_stream_state *os,ogg_packet *op) {
        return _packetout(os,op,1);
}

s32 ogg_stream_packetpeek(ogg_stream_state *os,ogg_packet *op) {
        return _packetout(os,op,0);
}

void ogg_packet_clear(ogg_packet *op) {
        gf_free(op->packet);
        memset(op, 0, sizeof(*op));
}

#endif /*GPAC_DISABLE_OGG*/
/* [<][>][^][v][top][bottom][index][help] */
root/src/media_tools/gpac_ogg.c

DEFINITIONS
