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FFmpeg/libavformat/avidec.c

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  1. /*

  2.  * AVI demuxer

  3.  * Copyright (c) 2001 Fabrice Bellard

  4.  *

  5.  * This file is part of FFmpeg.

  6.  *

  7.  * FFmpeg is free software; you can redistribute it and/or

  8.  * modify it under the terms of the GNU Lesser General Public

  9.  * License as published by the Free Software Foundation; either

  10.  * version 2.1 of the License, or (at your option) any later version.

  11.  *

  12.  * FFmpeg is distributed in the hope that it will be useful,

  13.  * but WITHOUT ANY WARRANTY; without even the implied warranty of

  14.  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

  15.  * Lesser General Public License for more details.

  16.  *

  17.  * You should have received a copy of the GNU Lesser General Public

  18.  * License along with FFmpeg; if not, write to the Free Software

  19.  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

  20.  */

  21. 

  22. #include "libavutil/intreadwrite.h"

  23. #include "libavutil/mathematics.h"

  24. #include "libavutil/bswap.h"

  25. #include "libavutil/opt.h"

  26. #include "libavutil/dict.h"

  27. #include "libavutil/avstring.h"

  28. #include "avformat.h"

  29. #include "avi.h"

  30. #include "dv.h"

  31. #include "riff.h"

  32. 

  33. #undef NDEBUG

  34. #include <assert.h>

  35. 

  36. typedef struct AVIStream {

  37.     int64_t frame_offset; /* current frame (video) or byte (audio) counter

  38.                          (used to compute the pts) */

  39.     int remaining;

  40.     int packet_size;

  41. 

  42.     int scale;

  43.     int rate;

  44.     int sample_size; /* size of one sample (or packet) (in the rate/scale sense) in bytes */

  45. 

  46.     int64_t cum_len; /* temporary storage (used during seek) */

  47. 

  48.     int prefix;                       ///< normally 'd'<<8 + 'c' or 'w'<<8 + 'b'

  49.     int prefix_count;

  50.     uint32_t pal[256];

  51.     int has_pal;

  52.     int dshow_block_align;            ///< block align variable used to emulate bugs in the MS dshow demuxer

  53. 

  54.     AVFormatContext *sub_ctx;

  55.     AVPacket sub_pkt;

  56.     uint8_t *sub_buffer;

  57. 

  58.     int64_t seek_pos;

  59. } AVIStream;

  60. 

  61. typedef struct {

  62.     const AVClass *class;

  63.     int64_t  riff_end;

  64.     int64_t  movi_end;

  65.     int64_t  fsize;

  66.     int64_t movi_list;

  67.     int64_t last_pkt_pos;

  68.     int index_loaded;

  69.     int is_odml;

  70.     int non_interleaved;

  71.     int stream_index;

  72.     DVDemuxContext* dv_demux;

  73.     int odml_depth;

  74.     int use_odml;

  75. #define MAX_ODML_DEPTH 1000

  76.     int64_t dts_max;

  77. } AVIContext;

  78. 

  79. 

  80. static const AVOption options[] = {

  81.     { "use_odml", "use odml index", offsetof(AVIContext, use_odml), AV_OPT_TYPE_INT, {.dbl = 1}, -1, 1, AV_OPT_FLAG_DECODING_PARAM},

  82.     { NULL },

  83. };

  84. 

  85. static const AVClass demuxer_class = {

  86.     "AVI demuxer",

  87.     av_default_item_name,

  88.     options,

  89.     LIBAVUTIL_VERSION_INT,

  90. };

  91. 

  92. 

  93. static const char avi_headers[][8] = {

  94.     { 'R', 'I', 'F', 'F',    'A', 'V', 'I', ' ' },

  95.     { 'R', 'I', 'F', 'F',    'A', 'V', 'I', 'X' },

  96.     { 'R', 'I', 'F', 'F',    'A', 'V', 'I', 0x19},

  97.     { 'O', 'N', '2', ' ',    'O', 'N', '2', 'f' },

  98.     { 'R', 'I', 'F', 'F',    'A', 'M', 'V', ' ' },

  99.     { 0 }

  100. };

  101. 

  102. static const AVMetadataConv avi_metadata_conv[] = {

  103.     { "strn", "title" },

  104.     { 0 },

  105. };

  106. 

  107. static int avi_load_index(AVFormatContext *s);

  108. static int guess_ni_flag(AVFormatContext *s);

  109. 

  110. #define print_tag(str, tag, size)                       \

  111.     av_dlog(NULL, "%s: tag=%c%c%c%c size=0x%x\n",       \

  112.            str, tag & 0xff,                             \

  113.            (tag >> 8) & 0xff,                           \

  114.            (tag >> 16) & 0xff,                          \

  115.            (tag >> 24) & 0xff,                          \

  116.            size)

  117. 

  118. static inline int get_duration(AVIStream *ast, int len){

  119.     if(ast->sample_size){

  120.         return len;

  121.     }else if (ast->dshow_block_align){

  122.         return (len + ast->dshow_block_align - 1)/ast->dshow_block_align;

  123.     }else

  124.         return 1;

  125. }

  126. 

  127. static int get_riff(AVFormatContext *s, AVIOContext *pb)

  128. {

  129.     AVIContext *avi = s->priv_data;

  130.     char header[8];

  131.     int i;

  132. 

  133.     /* check RIFF header */

  134.     avio_read(pb, header, 4);

  135.     avi->riff_end = avio_rl32(pb);  /* RIFF chunk size */

  136.     avi->riff_end += avio_tell(pb); /* RIFF chunk end */

  137.     avio_read(pb, header+4, 4);

  138. 

  139.     for(i=0; avi_headers[i][0]; i++)

  140.         if(!memcmp(header, avi_headers[i], 8))

  141.             break;

  142.     if(!avi_headers[i][0])

  143.         return -1;

  144. 

  145.     if(header[7] == 0x19)

  146.         av_log(s, AV_LOG_INFO, "This file has been generated by a totally broken muxer.\n");

  147. 

  148.     return 0;

  149. }

  150. 

  151. static int read_braindead_odml_indx(AVFormatContext *s, int frame_num){

  152.     AVIContext *avi = s->priv_data;

  153.     AVIOContext *pb = s->pb;

  154.     int longs_pre_entry= avio_rl16(pb);

  155.     int index_sub_type = avio_r8(pb);

  156.     int index_type     = avio_r8(pb);

  157.     int entries_in_use = avio_rl32(pb);

  158.     int chunk_id       = avio_rl32(pb);

  159.     int64_t base       = avio_rl64(pb);

  160.     int stream_id= 10*((chunk_id&0xFF) - '0') + (((chunk_id>>8)&0xFF) - '0');

  161.     AVStream *st;

  162.     AVIStream *ast;

  163.     int i;

  164.     int64_t last_pos= -1;

  165.     int64_t filesize= avi->fsize;

  166. 

  167.     av_dlog(s, "longs_pre_entry:%d index_type:%d entries_in_use:%d chunk_id:%X base:%16"PRIX64"\n",

  168.             longs_pre_entry,index_type, entries_in_use, chunk_id, base);

  169. 

  170.     if(stream_id >= s->nb_streams || stream_id < 0)

  171.         return -1;

  172.     st= s->streams[stream_id];

  173.     ast = st->priv_data;

  174. 

  175.     if(index_sub_type)

  176.         return -1;

  177. 

  178.     avio_rl32(pb);

  179. 

  180.     if(index_type && longs_pre_entry != 2)

  181.         return -1;

  182.     if(index_type>1)

  183.         return -1;

  184. 

  185.     if(filesize > 0 && base >= filesize){

  186.         av_log(s, AV_LOG_ERROR, "ODML index invalid\n");

  187.         if(base>>32 == (base & 0xFFFFFFFF) && (base & 0xFFFFFFFF) < filesize && filesize <= 0xFFFFFFFF)

  188.             base &= 0xFFFFFFFF;

  189.         else

  190.             return -1;

  191.     }

  192. 

  193.     for(i=0; i<entries_in_use; i++){

  194.         if(index_type){

  195.             int64_t pos= avio_rl32(pb) + base - 8;

  196.             int len    = avio_rl32(pb);

  197.             int key= len >= 0;

  198.             len &= 0x7FFFFFFF;

  199. 

  200. #ifdef DEBUG_SEEK

  201.             av_log(s, AV_LOG_ERROR, "pos:%"PRId64", len:%X\n", pos, len);

  202. #endif

  203.             if(url_feof(pb))

  204.                 return -1;

  205. 

  206.             if(last_pos == pos || pos == base - 8)

  207.                 avi->non_interleaved= 1;

  208.             if(last_pos != pos && (len || !ast->sample_size))

  209.                 av_add_index_entry(st, pos, ast->cum_len, len, 0, key ? AVINDEX_KEYFRAME : 0);

  210. 

  211.             ast->cum_len += get_duration(ast, len);

  212.             last_pos= pos;

  213.         }else{

  214.             int64_t offset, pos;

  215.             int duration;

  216.             offset = avio_rl64(pb);

  217.             avio_rl32(pb);       /* size */

  218.             duration = avio_rl32(pb);

  219. 

  220.             if(url_feof(pb))

  221.                 return -1;

  222. 

  223.             pos = avio_tell(pb);

  224. 

  225.             if(avi->odml_depth > MAX_ODML_DEPTH){

  226.                 av_log(s, AV_LOG_ERROR, "Too deeply nested ODML indexes\n");

  227.                 return -1;

  228.             }

  229. 

  230.             if(avio_seek(pb, offset+8, SEEK_SET) < 0)

  231.                 return -1;

  232.             avi->odml_depth++;

  233.             read_braindead_odml_indx(s, frame_num);

  234.             avi->odml_depth--;

  235.             frame_num += duration;

  236. 

  237.             if(avio_seek(pb, pos, SEEK_SET) < 0) {

  238.                 av_log(s, AV_LOG_ERROR, "Failed to restore position after reading index");

  239.                 return -1;

  240.             }

  241. 

  242.         }

  243.     }

  244.     avi->index_loaded=2;

  245.     return 0;

  246. }

  247. 

  248. static void clean_index(AVFormatContext *s){

  249.     int i;

  250.     int64_t j;

  251. 

  252.     for(i=0; i<s->nb_streams; i++){

  253.         AVStream *st = s->streams[i];

  254.         AVIStream *ast = st->priv_data;

  255.         int n= st->nb_index_entries;

  256.         int max= ast->sample_size;

  257.         int64_t pos, size, ts;

  258. 

  259.         if(n != 1 || ast->sample_size==0)

  260.             continue;

  261. 

  262.         while(max < 1024) max+=max;

  263. 

  264.         pos= st->index_entries[0].pos;

  265.         size= st->index_entries[0].size;

  266.         ts= st->index_entries[0].timestamp;

  267. 

  268.         for(j=0; j<size; j+=max){

  269.             av_add_index_entry(st, pos+j, ts+j, FFMIN(max, size-j), 0, AVINDEX_KEYFRAME);

  270.         }

  271.     }

  272. }

  273. 

  274. static int avi_read_tag(AVFormatContext *s, AVStream *st, uint32_t tag, uint32_t size)

  275. {

  276.     AVIOContext *pb = s->pb;

  277.     char key[5] = {0}, *value;

  278. 

  279.     size += (size & 1);

  280. 

  281.     if (size == UINT_MAX)

  282.         return -1;

  283.     value = av_malloc(size+1);

  284.     if (!value)

  285.         return -1;

  286.     avio_read(pb, value, size);

  287.     value[size]=0;

  288. 

  289.     AV_WL32(key, tag);

  290. 

  291.     return av_dict_set(st ? &st->metadata : &s->metadata, key, value,

  292.                             AV_DICT_DONT_STRDUP_VAL);

  293. }

  294. 

  295. static const char months[12][4] = { "Jan", "Feb", "Mar", "Apr", "May", "Jun",

  296.                                     "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" };

  297. 

  298. static void avi_metadata_creation_time(AVDictionary **metadata, char *date)

  299. {

  300.     char month[4], time[9], buffer[64];

  301.     int i, day, year;

  302.     /* parse standard AVI date format (ie. "Mon Mar 10 15:04:43 2003") */

  303.     if (sscanf(date, "%*3s%*[ ]%3s%*[ ]%2d%*[ ]%8s%*[ ]%4d",

  304.                month, &day, time, &year) == 4) {

  305.         for (i=0; i<12; i++)

  306.             if (!av_strcasecmp(month, months[i])) {

  307.                 snprintf(buffer, sizeof(buffer), "%.4d-%.2d-%.2d %s",

  308.                          year, i+1, day, time);

  309.                 av_dict_set(metadata, "creation_time", buffer, 0);

  310.             }

  311.     } else if (date[4] == '/' && date[7] == '/') {

  312.         date[4] = date[7] = '-';

  313.         av_dict_set(metadata, "creation_time", date, 0);

  314.     }

  315. }

  316. 

  317. static void avi_read_nikon(AVFormatContext *s, uint64_t end)

  318. {

  319.     while (avio_tell(s->pb) < end) {

  320.         uint32_t tag  = avio_rl32(s->pb);

  321.         uint32_t size = avio_rl32(s->pb);

  322.         switch (tag) {

  323.         case MKTAG('n', 'c', 't', 'g'): {  /* Nikon Tags */

  324.             uint64_t tag_end = avio_tell(s->pb) + size;

  325.             while (avio_tell(s->pb) < tag_end) {

  326.                 uint16_t tag  = avio_rl16(s->pb);

  327.                 uint16_t size = avio_rl16(s->pb);

  328.                 const char *name = NULL;

  329.                 char buffer[64] = {0};

  330.                 size -= avio_read(s->pb, buffer,

  331.                                    FFMIN(size, sizeof(buffer)-1));

  332.                 switch (tag) {

  333.                 case 0x03:  name = "maker";  break;

  334.                 case 0x04:  name = "model";  break;

  335.                 case 0x13:  name = "creation_time";

  336.                     if (buffer[4] == ':' && buffer[7] == ':')

  337.                         buffer[4] = buffer[7] = '-';

  338.                     break;

  339.                 }

  340.                 if (name)

  341.                     av_dict_set(&s->metadata, name, buffer, 0);

  342.                 avio_skip(s->pb, size);

  343.             }

  344.             break;

  345.         }

  346.         default:

  347.             avio_skip(s->pb, size);

  348.             break;

  349.         }

  350.     }

  351. }

  352. 

  353. static int avi_read_header(AVFormatContext *s, AVFormatParameters *ap)

  354. {

  355.     AVIContext *avi = s->priv_data;

  356.     AVIOContext *pb = s->pb;

  357.     unsigned int tag, tag1, handler;

  358.     int codec_type, stream_index, frame_period;

  359.     unsigned int size;

  360.     int i;

  361.     AVStream *st;

  362.     AVIStream *ast = NULL;

  363.     int avih_width=0, avih_height=0;

  364.     int amv_file_format=0;

  365.     uint64_t list_end = 0;

  366.     int ret;

  367. 

  368.     avi->stream_index= -1;

  369. 

  370.     if (get_riff(s, pb) < 0)

  371.         return -1;

  372. 

  373.     av_log(avi, AV_LOG_DEBUG, "use odml:%d\n", avi->use_odml);

  374. 

  375.     avi->fsize = avio_size(pb);

  376.     if(avi->fsize<=0 || avi->fsize < avi->riff_end)

  377.         avi->fsize= avi->riff_end == 8 ? INT64_MAX : avi->riff_end;

  378. 

  379.     /* first list tag */

  380.     stream_index = -1;

  381.     codec_type = -1;

  382.     frame_period = 0;

  383.     for(;;) {

  384.         if (url_feof(pb))

  385.             goto fail;

  386.         tag = avio_rl32(pb);

  387.         size = avio_rl32(pb);

  388. 

  389.         print_tag("tag", tag, size);

  390. 

  391.         switch(tag) {

  392.         case MKTAG('L', 'I', 'S', 'T'):

  393.             list_end = avio_tell(pb) + size;

  394.             /* Ignored, except at start of video packets. */

  395.             tag1 = avio_rl32(pb);

  396. 

  397.             print_tag("list", tag1, 0);

  398. 

  399.             if (tag1 == MKTAG('m', 'o', 'v', 'i')) {

  400.                 avi->movi_list = avio_tell(pb) - 4;

  401.                 if(size) avi->movi_end = avi->movi_list + size + (size & 1);

  402.                 else     avi->movi_end = avi->fsize;

  403.                 av_dlog(NULL, "movi end=%"PRIx64"\n", avi->movi_end);

  404.                 goto end_of_header;

  405.             }

  406.             else if (tag1 == MKTAG('I', 'N', 'F', 'O'))

  407.                 ff_read_riff_info(s, size - 4);

  408.             else if (tag1 == MKTAG('n', 'c', 'd', 't'))

  409.                 avi_read_nikon(s, list_end);

  410. 

  411.             break;

  412.         case MKTAG('I', 'D', 'I', 'T'): {

  413.             unsigned char date[64] = {0};

  414.             size += (size & 1);

  415.             size -= avio_read(pb, date, FFMIN(size, sizeof(date)-1));

  416.             avio_skip(pb, size);

  417.             avi_metadata_creation_time(&s->metadata, date);

  418.             break;

  419.         }

  420.         case MKTAG('d', 'm', 'l', 'h'):

  421.             avi->is_odml = 1;

  422.             avio_skip(pb, size + (size & 1));

  423.             break;

  424.         case MKTAG('a', 'm', 'v', 'h'):

  425.             amv_file_format=1;

  426.         case MKTAG('a', 'v', 'i', 'h'):

  427.             /* AVI header */

  428.             /* using frame_period is bad idea */

  429.             frame_period = avio_rl32(pb);

  430.             avio_rl32(pb); /* max. bytes per second */

  431.             avio_rl32(pb);

  432.             avi->non_interleaved |= avio_rl32(pb) & AVIF_MUSTUSEINDEX;

  433. 

  434.             avio_skip(pb, 2 * 4);

  435.             avio_rl32(pb);

  436.             avio_rl32(pb);

  437.             avih_width=avio_rl32(pb);

  438.             avih_height=avio_rl32(pb);

  439. 

  440.             avio_skip(pb, size - 10 * 4);

  441.             break;

  442.         case MKTAG('s', 't', 'r', 'h'):

  443.             /* stream header */

  444. 

  445.             tag1 = avio_rl32(pb);

  446.             handler = avio_rl32(pb); /* codec tag */

  447. 

  448.             if(tag1 == MKTAG('p', 'a', 'd', 's')){

  449.                 avio_skip(pb, size - 8);

  450.                 break;

  451.             }else{

  452.                 stream_index++;

  453.                 st = avformat_new_stream(s, NULL);

  454.                 if (!st)

  455.                     goto fail;

  456. 

  457.                 st->id = stream_index;

  458.                 ast = av_mallocz(sizeof(AVIStream));

  459.                 if (!ast)

  460.                     goto fail;

  461.                 st->priv_data = ast;

  462.             }

  463.             if(amv_file_format)

  464.                 tag1 = stream_index ? MKTAG('a','u','d','s') : MKTAG('v','i','d','s');

  465. 

  466.             print_tag("strh", tag1, -1);

  467. 

  468.             if(tag1 == MKTAG('i', 'a', 'v', 's') || tag1 == MKTAG('i', 'v', 'a', 's')){

  469.                 int64_t dv_dur;

  470. 

  471.                 /*

  472.                  * After some consideration -- I don't think we

  473.                  * have to support anything but DV in type1 AVIs.

  474.                  */

  475.                 if (s->nb_streams != 1)

  476.                     goto fail;

  477. 

  478.                 if (handler != MKTAG('d', 'v', 's', 'd') &&

  479.                     handler != MKTAG('d', 'v', 'h', 'd') &&

  480.                     handler != MKTAG('d', 'v', 's', 'l'))

  481.                    goto fail;

  482. 

  483.                 ast = s->streams[0]->priv_data;

  484.                 av_freep(&s->streams[0]->codec->extradata);

  485.                 av_freep(&s->streams[0]->codec);

  486.                 av_freep(&s->streams[0]);

  487.                 s->nb_streams = 0;

  488.                 if (CONFIG_DV_DEMUXER) {

  489.                     avi->dv_demux = avpriv_dv_init_demux(s);

  490.                     if (!avi->dv_demux)

  491.                         goto fail;

  492.                 }

  493.                 s->streams[0]->priv_data = ast;

  494.                 avio_skip(pb, 3 * 4);

  495.                 ast->scale = avio_rl32(pb);

  496.                 ast->rate = avio_rl32(pb);

  497.                 avio_skip(pb, 4);  /* start time */

  498. 

  499.                 dv_dur = avio_rl32(pb);

  500.                 if (ast->scale > 0 && ast->rate > 0 && dv_dur > 0) {

  501.                     dv_dur *= AV_TIME_BASE;

  502.                     s->duration = av_rescale(dv_dur, ast->scale, ast->rate);

  503.                 }

  504.                 /*

  505.                  * else, leave duration alone; timing estimation in utils.c

  506.                  *      will make a guess based on bitrate.

  507.                  */

  508. 

  509.                 stream_index = s->nb_streams - 1;

  510.                 avio_skip(pb, size - 9*4);

  511.                 break;

  512.             }

  513. 

  514.             assert(stream_index < s->nb_streams);

  515.             st->codec->stream_codec_tag= handler;

  516. 

  517.             avio_rl32(pb); /* flags */

  518.             avio_rl16(pb); /* priority */

  519.             avio_rl16(pb); /* language */

  520.             avio_rl32(pb); /* initial frame */

  521.             ast->scale = avio_rl32(pb);

  522.             ast->rate = avio_rl32(pb);

  523.             if(!(ast->scale && ast->rate)){

  524.                 av_log(s, AV_LOG_WARNING, "scale/rate is %u/%u which is invalid. (This file has been generated by broken software.)\n", ast->scale, ast->rate);

  525.                 if(frame_period){

  526.                     ast->rate = 1000000;

  527.                     ast->scale = frame_period;

  528.                 }else{

  529.                     ast->rate = 25;

  530.                     ast->scale = 1;

  531.                 }

  532.             }

  533.             av_set_pts_info(st, 64, ast->scale, ast->rate);

  534. 

  535.             ast->cum_len=avio_rl32(pb); /* start */

  536.             st->nb_frames = avio_rl32(pb);

  537. 

  538.             st->start_time = 0;

  539.             avio_rl32(pb); /* buffer size */

  540.             avio_rl32(pb); /* quality */

  541.             ast->sample_size = avio_rl32(pb); /* sample ssize */

  542.             ast->cum_len *= FFMAX(1, ast->sample_size);

  543. //            av_log(s, AV_LOG_DEBUG, "%d %d %d %d\n", ast->rate, ast->scale, ast->start, ast->sample_size);

  544. 

  545.             switch(tag1) {

  546.             case MKTAG('v', 'i', 'd', 's'):

  547.                 codec_type = AVMEDIA_TYPE_VIDEO;

  548. 

  549.                 ast->sample_size = 0;

  550.                 break;

  551.             case MKTAG('a', 'u', 'd', 's'):

  552.                 codec_type = AVMEDIA_TYPE_AUDIO;

  553.                 break;

  554.             case MKTAG('t', 'x', 't', 's'):

  555.                 codec_type = AVMEDIA_TYPE_SUBTITLE;

  556.                 break;

  557.             case MKTAG('d', 'a', 't', 's'):

  558.                 codec_type = AVMEDIA_TYPE_DATA;

  559.                 break;

  560.             default:

  561.                 av_log(s, AV_LOG_INFO, "unknown stream type %X\n", tag1);

  562.             }

  563.             if(ast->sample_size == 0)

  564.                 st->duration = st->nb_frames;

  565.             ast->frame_offset= ast->cum_len;

  566.             avio_skip(pb, size - 12 * 4);

  567.             break;

  568.         case MKTAG('s', 't', 'r', 'f'):

  569.             /* stream header */

  570.             if (!size)

  571.                 break;

  572.             if (stream_index >= (unsigned)s->nb_streams || avi->dv_demux) {

  573.                 avio_skip(pb, size);

  574.             } else {

  575.                 uint64_t cur_pos = avio_tell(pb);

  576.                 if (cur_pos < list_end)

  577.                     size = FFMIN(size, list_end - cur_pos);

  578.                 st = s->streams[stream_index];

  579.                 switch(codec_type) {

  580.                 case AVMEDIA_TYPE_VIDEO:

  581.                     if(amv_file_format){

  582.                         st->codec->width=avih_width;

  583.                         st->codec->height=avih_height;

  584.                         st->codec->codec_type = AVMEDIA_TYPE_VIDEO;

  585.                         st->codec->codec_id = CODEC_ID_AMV;

  586.                         avio_skip(pb, size);

  587.                         break;

  588.                     }

  589.                     tag1 = ff_get_bmp_header(pb, st);

  590. 

  591.                     if (tag1 == MKTAG('D', 'X', 'S', 'B') || tag1 == MKTAG('D','X','S','A')) {

  592.                         st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;

  593.                         st->codec->codec_tag = tag1;

  594.                         st->codec->codec_id = CODEC_ID_XSUB;

  595.                         break;

  596.                     }

  597. 

  598.                     if(size > 10*4 && size<(1<<30)){

  599.                         st->codec->extradata_size= size - 10*4;

  600.                         st->codec->extradata= av_malloc(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);

  601.                         if (!st->codec->extradata) {

  602.                             st->codec->extradata_size= 0;

  603.                             return AVERROR(ENOMEM);

  604.                         }

  605.                         avio_read(pb, st->codec->extradata, st->codec->extradata_size);

  606.                     }

  607. 

  608.                     if(st->codec->extradata_size & 1) //FIXME check if the encoder really did this correctly

  609.                         avio_r8(pb);

  610. 

  611.                     /* Extract palette from extradata if bpp <= 8. */

  612.                     /* This code assumes that extradata contains only palette. */

  613.                     /* This is true for all paletted codecs implemented in FFmpeg. */

  614.                     if (st->codec->extradata_size && (st->codec->bits_per_coded_sample <= 8)) {

  615.                         int pal_size = (1 << st->codec->bits_per_coded_sample) << 2;

  616.                         const uint8_t *pal_src;

  617. 

  618.                         pal_size = FFMIN(pal_size, st->codec->extradata_size);

  619.                         pal_src = st->codec->extradata + st->codec->extradata_size - pal_size;

  620. #if HAVE_BIGENDIAN

  621.                         for (i = 0; i < pal_size/4; i++)

  622.                             ast->pal[i] = AV_RL32(pal_src+4*i);

  623. #else

  624.                         memcpy(ast->pal, pal_src, pal_size);

  625. #endif

  626.                         ast->has_pal = 1;

  627.                     }

  628. 

  629.                     print_tag("video", tag1, 0);

  630. 

  631.                     st->codec->codec_type = AVMEDIA_TYPE_VIDEO;

  632.                     st->codec->codec_tag = tag1;

  633.                     st->codec->codec_id = ff_codec_get_id(ff_codec_bmp_tags, tag1);

  634.                     st->need_parsing = AVSTREAM_PARSE_HEADERS; // This is needed to get the pict type which is necessary for generating correct pts.

  635.                     // Support "Resolution 1:1" for Avid AVI Codec

  636.                     if(tag1 == MKTAG('A', 'V', 'R', 'n') &&

  637.                        st->codec->extradata_size >= 31 &&

  638.                        !memcmp(&st->codec->extradata[28], "1:1", 3))

  639.                         st->codec->codec_id = CODEC_ID_RAWVIDEO;

  640. 

  641.                     if(st->codec->codec_tag==0 && st->codec->height > 0 && st->codec->extradata_size < 1U<<30){

  642.                         st->codec->extradata_size+= 9;

  643.                         st->codec->extradata= av_realloc_f(st->codec->extradata, 1, st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);

  644.                         if(st->codec->extradata)

  645.                             memcpy(st->codec->extradata + st->codec->extradata_size - 9, "BottomUp", 9);

  646.                     }

  647.                     st->codec->height= FFABS(st->codec->height);

  648. 

  649. //                    avio_skip(pb, size - 5 * 4);

  650.                     break;

  651.                 case AVMEDIA_TYPE_AUDIO:

  652.                     ret = ff_get_wav_header(pb, st->codec, size);

  653.                     if (ret < 0)

  654.                         return ret;

  655.                     ast->dshow_block_align= st->codec->block_align;

  656.                     if(ast->sample_size && st->codec->block_align && ast->sample_size != st->codec->block_align){

  657.                         av_log(s, AV_LOG_WARNING, "sample size (%d) != block align (%d)\n", ast->sample_size, st->codec->block_align);

  658.                         ast->sample_size= st->codec->block_align;

  659.                     }

  660.                     if (size&1) /* 2-aligned (fix for Stargate SG-1 - 3x18 - Shades of Grey.avi) */

  661.                         avio_skip(pb, 1);

  662.                     /* Force parsing as several audio frames can be in

  663.                      * one packet and timestamps refer to packet start. */

  664.                     st->need_parsing = AVSTREAM_PARSE_TIMESTAMPS;

  665.                     /* ADTS header is in extradata, AAC without header must be

  666.                      * stored as exact frames. Parser not needed and it will

  667.                      * fail. */

  668.                     if (st->codec->codec_id == CODEC_ID_AAC && st->codec->extradata_size)

  669.                         st->need_parsing = AVSTREAM_PARSE_NONE;

  670.                     /* AVI files with Xan DPCM audio (wrongly) declare PCM

  671.                      * audio in the header but have Axan as stream_code_tag. */

  672.                     if (st->codec->stream_codec_tag == AV_RL32("Axan")){

  673.                         st->codec->codec_id  = CODEC_ID_XAN_DPCM;

  674.                         st->codec->codec_tag = 0;

  675.                         ast->dshow_block_align = 0;

  676.                     }

  677.                     if (amv_file_format){

  678.                         st->codec->codec_id  = CODEC_ID_ADPCM_IMA_AMV;

  679.                         ast->dshow_block_align = 0;

  680.                     }

  681.                     break;

  682.                 case AVMEDIA_TYPE_SUBTITLE:

  683.                     st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;

  684.                     st->request_probe= 1;

  685.                     break;

  686.                 default:

  687.                     st->codec->codec_type = AVMEDIA_TYPE_DATA;

  688.                     st->codec->codec_id= CODEC_ID_NONE;

  689.                     st->codec->codec_tag= 0;

  690.                     avio_skip(pb, size);

  691.                     break;

  692.                 }

  693.             }

  694.             break;

  695.         case MKTAG('i', 'n', 'd', 'x'):

  696.             i= avio_tell(pb);

  697.             if(pb->seekable && !(s->flags & AVFMT_FLAG_IGNIDX) && avi->use_odml &&

  698.                read_braindead_odml_indx(s, 0) < 0 && s->error_recognition >= FF_ER_EXPLODE){

  699.                 goto fail;            }

  700.             avio_seek(pb, i+size, SEEK_SET);

  701.             break;

  702.         case MKTAG('v', 'p', 'r', 'p'):

  703.             if(stream_index < (unsigned)s->nb_streams && size > 9*4){

  704.                 AVRational active, active_aspect;

  705. 

  706.                 st = s->streams[stream_index];

  707.                 avio_rl32(pb);

  708.                 avio_rl32(pb);

  709.                 avio_rl32(pb);

  710.                 avio_rl32(pb);

  711.                 avio_rl32(pb);

  712. 

  713.                 active_aspect.den= avio_rl16(pb);

  714.                 active_aspect.num= avio_rl16(pb);

  715.                 active.num       = avio_rl32(pb);

  716.                 active.den       = avio_rl32(pb);

  717.                 avio_rl32(pb); //nbFieldsPerFrame

  718. 

  719.                 if(active_aspect.num && active_aspect.den && active.num && active.den){

  720.                     st->sample_aspect_ratio= av_div_q(active_aspect, active);

  721. //av_log(s, AV_LOG_ERROR, "vprp %d/%d %d/%d\n", active_aspect.num, active_aspect.den, active.num, active.den);

  722.                 }

  723.                 size -= 9*4;

  724.             }

  725.             avio_skip(pb, size);

  726.             break;

  727.         case MKTAG('s', 't', 'r', 'n'):

  728.             if(s->nb_streams){

  729.                 avi_read_tag(s, s->streams[s->nb_streams-1], tag, size);

  730.                 break;

  731.             }

  732.         default:

  733.             if(size > 1000000){

  734.                 av_log(s, AV_LOG_ERROR, "Something went wrong during header parsing, "

  735.                                         "I will ignore it and try to continue anyway.\n");

  736.                 if (s->error_recognition >= FF_ER_EXPLODE) goto fail;

  737.                 avi->movi_list = avio_tell(pb) - 4;

  738.                 avi->movi_end  = avi->fsize;

  739.                 goto end_of_header;

  740.             }

  741.             /* skip tag */

  742.             size += (size & 1);

  743.             avio_skip(pb, size);

  744.             break;

  745.         }

  746.     }

  747.  end_of_header:

  748.     /* check stream number */

  749.     if (stream_index != s->nb_streams - 1) {

  750.     fail:

  751.         return -1;

  752.     }

  753. 

  754.     if(!avi->index_loaded && pb->seekable)

  755.         avi_load_index(s);

  756.     avi->index_loaded |= 1;

  757.     avi->non_interleaved |= guess_ni_flag(s) | (s->flags & AVFMT_FLAG_SORT_DTS);

  758.     for(i=0; i<s->nb_streams; i++){

  759.         AVStream *st = s->streams[i];

  760.         if(st->nb_index_entries)

  761.             break;

  762.     }

  763.     // DV-in-AVI cannot be non-interleaved, if set this must be

  764.     // a mis-detection.

  765.     if(avi->dv_demux)

  766.         avi->non_interleaved=0;

  767.     if(i==s->nb_streams && avi->non_interleaved) {

  768.         av_log(s, AV_LOG_WARNING, "non-interleaved AVI without index, switching to interleaved\n");

  769.         avi->non_interleaved=0;

  770.     }

  771. 

  772.     if(avi->non_interleaved) {

  773.         av_log(s, AV_LOG_INFO, "non-interleaved AVI\n");

  774.         clean_index(s);

  775.     }

  776. 

  777.     ff_metadata_conv_ctx(s, NULL, avi_metadata_conv);

  778.     ff_metadata_conv_ctx(s, NULL, ff_riff_info_conv);

  779. 

  780.     return 0;

  781. }

  782. 

  783. static int read_gab2_sub(AVStream *st, AVPacket *pkt) {

  784.     if (!strcmp(pkt->data, "GAB2") && AV_RL16(pkt->data+5) == 2) {

  785.         uint8_t desc[256];

  786.         int score = AVPROBE_SCORE_MAX / 2, ret;

  787.         AVIStream *ast = st->priv_data;

  788.         AVInputFormat *sub_demuxer;

  789.         AVRational time_base;

  790.         AVIOContext *pb = avio_alloc_context( pkt->data + 7,

  791.                                               pkt->size - 7,

  792.                                               0, NULL, NULL, NULL, NULL);

  793.         AVProbeData pd;

  794.         unsigned int desc_len = avio_rl32(pb);

  795. 

  796.         if (desc_len > pb->buf_end - pb->buf_ptr)

  797.             goto error;

  798. 

  799.         ret = avio_get_str16le(pb, desc_len, desc, sizeof(desc));

  800.         avio_skip(pb, desc_len - ret);

  801.         if (*desc)

  802.             av_dict_set(&st->metadata, "title", desc, 0);

  803. 

  804.         avio_rl16(pb);   /* flags? */

  805.         avio_rl32(pb);   /* data size */

  806. 

  807.         pd = (AVProbeData) { .buf = pb->buf_ptr, .buf_size = pb->buf_end - pb->buf_ptr };

  808.         if (!(sub_demuxer = av_probe_input_format2(&pd, 1, &score)))

  809.             goto error;

  810. 

  811.         if (!(ast->sub_ctx = avformat_alloc_context()))

  812.             goto error;

  813. 

  814.         ast->sub_ctx->pb      = pb;

  815.         if (!avformat_open_input(&ast->sub_ctx, "", sub_demuxer, NULL)) {

  816.             av_read_packet(ast->sub_ctx, &ast->sub_pkt);

  817.             *st->codec = *ast->sub_ctx->streams[0]->codec;

  818.             ast->sub_ctx->streams[0]->codec->extradata = NULL;

  819.             time_base = ast->sub_ctx->streams[0]->time_base;

  820.             av_set_pts_info(st, 64, time_base.num, time_base.den);

  821.         }

  822.         ast->sub_buffer = pkt->data;

  823.         memset(pkt, 0, sizeof(*pkt));

  824.         return 1;

  825. error:

  826.         av_freep(&pb);

  827.     }

  828.     return 0;

  829. }

  830. 

  831. static AVStream *get_subtitle_pkt(AVFormatContext *s, AVStream *next_st,

  832.                                   AVPacket *pkt)

  833. {

  834.     AVIStream *ast, *next_ast = next_st->priv_data;

  835.     int64_t ts, next_ts, ts_min = INT64_MAX;

  836.     AVStream *st, *sub_st = NULL;

  837.     int i;

  838. 

  839.     next_ts = av_rescale_q(next_ast->frame_offset, next_st->time_base,

  840.                            AV_TIME_BASE_Q);

  841. 

  842.     for (i=0; i<s->nb_streams; i++) {

  843.         st  = s->streams[i];

  844.         ast = st->priv_data;

  845.         if (st->discard < AVDISCARD_ALL && ast && ast->sub_pkt.data) {

  846.             ts = av_rescale_q(ast->sub_pkt.dts, st->time_base, AV_TIME_BASE_Q);

  847.             if (ts <= next_ts && ts < ts_min) {

  848.                 ts_min = ts;

  849.                 sub_st = st;

  850.             }

  851.         }

  852.     }

  853. 

  854.     if (sub_st) {

  855.         ast = sub_st->priv_data;

  856.         *pkt = ast->sub_pkt;

  857.         pkt->stream_index = sub_st->index;

  858.         if (av_read_packet(ast->sub_ctx, &ast->sub_pkt) < 0)

  859.             ast->sub_pkt.data = NULL;

  860.     }

  861.     return sub_st;

  862. }

  863. 

  864. static int get_stream_idx(int *d){

  865.     if(    d[0] >= '0' && d[0] <= '9'

  866.         && d[1] >= '0' && d[1] <= '9'){

  867.         return (d[0] - '0') * 10 + (d[1] - '0');

  868.     }else{

  869.         return 100; //invalid stream ID

  870.     }

  871. }

  872. 

  873. static int avi_sync(AVFormatContext *s, int exit_early)

  874. {

  875.     AVIContext *avi = s->priv_data;

  876.     AVIOContext *pb = s->pb;

  877.     int n;

  878.     unsigned int d[8];

  879.     unsigned int size;

  880.     int64_t i, sync;

  881. 

  882. start_sync:

  883.     memset(d, -1, sizeof(d));

  884.     for(i=sync=avio_tell(pb); !url_feof(pb); i++) {

  885.         int j;

  886. 

  887.         for(j=0; j<7; j++)

  888.             d[j]= d[j+1];

  889.         d[7]= avio_r8(pb);

  890. 

  891.         size= d[4] + (d[5]<<8) + (d[6]<<16) + (d[7]<<24);

  892. 

  893.         n= get_stream_idx(d+2);

  894. //av_log(s, AV_LOG_DEBUG, "%X %X %X %X %X %X %X %X %"PRId64" %d %d\n", d[0], d[1], d[2], d[3], d[4], d[5], d[6], d[7], i, size, n);

  895.         if(i + (uint64_t)size > avi->fsize || d[0] > 127)

  896.             continue;

  897. 

  898.         //parse ix##

  899.         if(  (d[0] == 'i' && d[1] == 'x' && n < s->nb_streams)

  900.         //parse JUNK

  901.            ||(d[0] == 'J' && d[1] == 'U' && d[2] == 'N' && d[3] == 'K')

  902.            ||(d[0] == 'i' && d[1] == 'd' && d[2] == 'x' && d[3] == '1')){

  903.             avio_skip(pb, size);

  904. //av_log(s, AV_LOG_DEBUG, "SKIP\n");

  905.             goto start_sync;

  906.         }

  907. 

  908.         //parse stray LIST

  909.         if(d[0] == 'L' && d[1] == 'I' && d[2] == 'S' && d[3] == 'T'){

  910.             avio_skip(pb, 4);

  911.             goto start_sync;

  912.         }

  913. 

  914.         n= get_stream_idx(d);

  915. 

  916.         if(!((i-avi->last_pkt_pos)&1) && get_stream_idx(d+1) < s->nb_streams)

  917.             continue;

  918. 

  919.         //detect ##ix chunk and skip

  920.         if(d[2] == 'i' && d[3] == 'x' && n < s->nb_streams){

  921.             avio_skip(pb, size);

  922.             goto start_sync;

  923.         }

  924. 

  925.         //parse ##dc/##wb

  926.         if(n < s->nb_streams){

  927.             AVStream *st;

  928.             AVIStream *ast;

  929.             st = s->streams[n];

  930.             ast = st->priv_data;

  931. 

  932.             if(s->nb_streams>=2){

  933.                 AVStream *st1  = s->streams[1];

  934.                 AVIStream *ast1= st1->priv_data;

  935.                 //workaround for broken small-file-bug402.avi

  936.                 if(   d[2] == 'w' && d[3] == 'b'

  937.                    && n==0

  938.                    && st ->codec->codec_type == AVMEDIA_TYPE_VIDEO

  939.                    && st1->codec->codec_type == AVMEDIA_TYPE_AUDIO

  940.                    && ast->prefix == 'd'*256+'c'

  941.                    && (d[2]*256+d[3] == ast1->prefix || !ast1->prefix_count)

  942.                   ){

  943.                     n=1;

  944.                     st = st1;

  945.                     ast = ast1;

  946.                     av_log(s, AV_LOG_WARNING, "Invalid stream + prefix combination, assuming audio.\n");

  947.                 }

  948.             }

  949. 

  950. 

  951.             if(   (st->discard >= AVDISCARD_DEFAULT && size==0)

  952.                /*|| (st->discard >= AVDISCARD_NONKEY && !(pkt->flags & AV_PKT_FLAG_KEY))*/ //FIXME needs a little reordering

  953.                || st->discard >= AVDISCARD_ALL){

  954.                 if (!exit_early) {

  955.                     ast->frame_offset += get_duration(ast, size);

  956.                 }

  957.                 avio_skip(pb, size);

  958.                 goto start_sync;

  959.             }

  960. 

  961.             if (d[2] == 'p' && d[3] == 'c' && size<=4*256+4) {

  962.                 int k = avio_r8(pb);

  963.                 int last = (k + avio_r8(pb) - 1) & 0xFF;

  964. 

  965.                 avio_rl16(pb); //flags

  966. 

  967.                 for (; k <= last; k++)

  968.                     ast->pal[k] = avio_rb32(pb)>>8;// b + (g << 8) + (r << 16);

  969.                 ast->has_pal= 1;

  970.                 goto start_sync;

  971.             } else if(   ((ast->prefix_count<5 || sync+9 > i) && d[2]<128 && d[3]<128) ||

  972.                          d[2]*256+d[3] == ast->prefix /*||

  973.                          (d[2] == 'd' && d[3] == 'c') ||

  974.                          (d[2] == 'w' && d[3] == 'b')*/) {

  975. 

  976.                 if (exit_early)

  977.                     return 0;

  978. //av_log(s, AV_LOG_DEBUG, "OK\n");

  979.                 if(d[2]*256+d[3] == ast->prefix)

  980.                     ast->prefix_count++;

  981.                 else{

  982.                     ast->prefix= d[2]*256+d[3];

  983.                     ast->prefix_count= 0;

  984.                 }

  985. 

  986.                 avi->stream_index= n;

  987.                 ast->packet_size= size + 8;

  988.                 ast->remaining= size;

  989. 

  990.                 if(size || !ast->sample_size){

  991.                     uint64_t pos= avio_tell(pb) - 8;

  992.                     if(!st->index_entries || !st->nb_index_entries || st->index_entries[st->nb_index_entries - 1].pos < pos){

  993.                         av_add_index_entry(st, pos, ast->frame_offset, size, 0, AVINDEX_KEYFRAME);

  994.                     }

  995.                 }

  996.                 return 0;

  997.             }

  998.         }

  999.     }

  1000. 

  1001.     if(pb->error)

  1002.         return pb->error;

  1003.     return AVERROR_EOF;

  1004. }

  1005. 

  1006. static int avi_read_packet(AVFormatContext *s, AVPacket *pkt)

  1007. {

  1008.     AVIContext *avi = s->priv_data;

  1009.     AVIOContext *pb = s->pb;

  1010.     int err;

  1011.     void* dstr;

  1012. 

  1013.     if (CONFIG_DV_DEMUXER && avi->dv_demux) {

  1014.         int size = avpriv_dv_get_packet(avi->dv_demux, pkt);

  1015.         if (size >= 0)

  1016.             return size;

  1017.     }

  1018. 

  1019.     if(avi->non_interleaved){

  1020.         int best_stream_index = 0;

  1021.         AVStream *best_st= NULL;

  1022.         AVIStream *best_ast;

  1023.         int64_t best_ts= INT64_MAX;

  1024.         int i;

  1025. 

  1026.         for(i=0; i<s->nb_streams; i++){

  1027.             AVStream *st = s->streams[i];

  1028.             AVIStream *ast = st->priv_data;

  1029.             int64_t ts= ast->frame_offset;

  1030.             int64_t last_ts;

  1031. 

  1032.             if(!st->nb_index_entries)

  1033.                 continue;

  1034. 

  1035.             last_ts = st->index_entries[st->nb_index_entries - 1].timestamp;

  1036.             if(!ast->remaining && ts > last_ts)

  1037.                 continue;

  1038. 

  1039.             ts = av_rescale_q(ts, st->time_base, (AVRational){FFMAX(1, ast->sample_size), AV_TIME_BASE});

  1040. 

  1041. //            av_log(s, AV_LOG_DEBUG, "%"PRId64" %d/%d %"PRId64"\n", ts, st->time_base.num, st->time_base.den, ast->frame_offset);

  1042.             if(ts < best_ts){

  1043.                 best_ts= ts;

  1044.                 best_st= st;

  1045.                 best_stream_index= i;

  1046.             }

  1047.         }

  1048.         if(!best_st)

  1049.             return AVERROR_EOF;

  1050. 

  1051.         best_ast = best_st->priv_data;

  1052.         best_ts = av_rescale_q(best_ts, (AVRational){FFMAX(1, best_ast->sample_size), AV_TIME_BASE}, best_st->time_base);

  1053.         if(best_ast->remaining)

  1054.             i= av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY | AVSEEK_FLAG_BACKWARD);

  1055.         else{

  1056.             i= av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY);

  1057.             if(i>=0)

  1058.                 best_ast->frame_offset= best_st->index_entries[i].timestamp;

  1059.         }

  1060. 

  1061. //        av_log(s, AV_LOG_DEBUG, "%d\n", i);

  1062.         if(i>=0){

  1063.             int64_t pos= best_st->index_entries[i].pos;

  1064.             pos += best_ast->packet_size - best_ast->remaining;

  1065.             if(avio_seek(s->pb, pos + 8, SEEK_SET) < 0)

  1066.               return AVERROR_EOF;

  1067. //        av_log(s, AV_LOG_DEBUG, "pos=%"PRId64"\n", pos);

  1068. 

  1069.             assert(best_ast->remaining <= best_ast->packet_size);

  1070. 

  1071.             avi->stream_index= best_stream_index;

  1072.             if(!best_ast->remaining)

  1073.                 best_ast->packet_size=

  1074.                 best_ast->remaining= best_st->index_entries[i].size;

  1075.         }

  1076.         else

  1077.           return AVERROR_EOF;

  1078.     }

  1079. 

  1080. resync:

  1081.     if(avi->stream_index >= 0){

  1082.         AVStream *st= s->streams[ avi->stream_index ];

  1083.         AVIStream *ast= st->priv_data;

  1084.         int size, err;

  1085. 

  1086.         if(get_subtitle_pkt(s, st, pkt))

  1087.             return 0;

  1088. 

  1089.         if(ast->sample_size <= 1) // minorityreport.AVI block_align=1024 sample_size=1 IMA-ADPCM

  1090.             size= INT_MAX;

  1091.         else if(ast->sample_size < 32)

  1092.             // arbitrary multiplier to avoid tiny packets for raw PCM data

  1093.             size= 1024*ast->sample_size;

  1094.         else

  1095.             size= ast->sample_size;

  1096. 

  1097.         if(size > ast->remaining)

  1098.             size= ast->remaining;

  1099.         avi->last_pkt_pos= avio_tell(pb);

  1100.         err= av_get_packet(pb, pkt, size);

  1101.         if(err<0)

  1102.             return err;

  1103. 

  1104.         if(ast->has_pal && pkt->data && pkt->size<(unsigned)INT_MAX/2){

  1105.             uint8_t *pal;

  1106.             pal = av_packet_new_side_data(pkt, AV_PKT_DATA_PALETTE, AVPALETTE_SIZE);

  1107.             if(!pal){

  1108.                 av_log(s, AV_LOG_ERROR, "Failed to allocate data for palette\n");

  1109.             }else{

  1110.                 memcpy(pal, ast->pal, AVPALETTE_SIZE);

  1111.                 ast->has_pal = 0;

  1112.             }

  1113.         }

  1114. 

  1115.         if (CONFIG_DV_DEMUXER && avi->dv_demux) {

  1116.             dstr = pkt->destruct;

  1117.             size = avpriv_dv_produce_packet(avi->dv_demux, pkt,

  1118.                                     pkt->data, pkt->size, pkt->pos);

  1119.             pkt->destruct = dstr;

  1120.             pkt->flags |= AV_PKT_FLAG_KEY;

  1121.             if (size < 0)

  1122.                 av_free_packet(pkt);

  1123.         } else if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE

  1124.                    && !st->codec->codec_tag && read_gab2_sub(st, pkt)) {

  1125.             ast->frame_offset++;

  1126.             avi->stream_index = -1;

  1127.             ast->remaining = 0;

  1128.             goto resync;

  1129.         } else {

  1130.             /* XXX: How to handle B-frames in AVI? */

  1131.             pkt->dts = ast->frame_offset;

  1132. //                pkt->dts += ast->start;

  1133.             if(ast->sample_size)

  1134.                 pkt->dts /= ast->sample_size;

  1135. //av_log(s, AV_LOG_DEBUG, "dts:%"PRId64" offset:%"PRId64" %d/%d smpl_siz:%d base:%d st:%d size:%d\n", pkt->dts, ast->frame_offset, ast->scale, ast->rate, ast->sample_size, AV_TIME_BASE, avi->stream_index, size);

  1136.             pkt->stream_index = avi->stream_index;

  1137. 

  1138.             if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {

  1139.                 AVIndexEntry *e;

  1140.                 int index;

  1141.                 assert(st->index_entries);

  1142. 

  1143.                 index= av_index_search_timestamp(st, ast->frame_offset, 0);

  1144.                 e= &st->index_entries[index];

  1145. 

  1146.                 if(index >= 0 && e->timestamp == ast->frame_offset){

  1147.                     if (index == st->nb_index_entries-1){

  1148.                         int key=1;

  1149.                         int i;

  1150.                         uint32_t state=-1;

  1151.                         for(i=0; i<FFMIN(size,256); i++){

  1152.                             if(st->codec->codec_id == CODEC_ID_MPEG4){

  1153.                                 if(state == 0x1B6){

  1154.                                     key= !(pkt->data[i]&0xC0);

  1155.                                     break;

  1156.                                 }

  1157.                             }else

  1158.                                 break;

  1159.                             state= (state<<8) + pkt->data[i];

  1160.                         }

  1161.                         if(!key)

  1162.                             e->flags &= ~AVINDEX_KEYFRAME;

  1163.                     }

  1164.                     if (e->flags & AVINDEX_KEYFRAME)

  1165.                         pkt->flags |= AV_PKT_FLAG_KEY;

  1166.                 }

  1167.             } else {

  1168.                 pkt->flags |= AV_PKT_FLAG_KEY;

  1169.             }

  1170.             ast->frame_offset += get_duration(ast, pkt->size);

  1171.         }

  1172.         ast->remaining -= size;

  1173.         if(!ast->remaining){

  1174.             avi->stream_index= -1;

  1175.             ast->packet_size= 0;

  1176.         }

  1177. 

  1178.         if(!avi->non_interleaved && pkt->pos >= 0 && ast->seek_pos > pkt->pos){

  1179.             av_free_packet(pkt);

  1180.             goto resync;

  1181.         }

  1182.         ast->seek_pos= 0;

  1183. 

  1184.         if(!avi->non_interleaved && st->nb_index_entries>1 && avi->index_loaded>1){

  1185.             int64_t dts= av_rescale_q(pkt->dts, st->time_base, AV_TIME_BASE_Q);

  1186. 

  1187.             if(avi->dts_max - dts > 2*AV_TIME_BASE){

  1188.                 avi->non_interleaved= 1;

  1189.                 av_log(s, AV_LOG_INFO, "Switching to NI mode, due to poor interleaving\n");

  1190.             }else if(avi->dts_max < dts)

  1191.                 avi->dts_max = dts;

  1192.         }

  1193. 

  1194.         return size;

  1195.     }

  1196. 

  1197.     if ((err = avi_sync(s, 0)) < 0)

  1198.         return err;

  1199.     goto resync;

  1200. }

  1201. 

  1202. /* XXX: We make the implicit supposition that the positions are sorted

  1203.    for each stream. */

  1204. static int avi_read_idx1(AVFormatContext *s, int size)

  1205. {

  1206.     AVIContext *avi = s->priv_data;

  1207.     AVIOContext *pb = s->pb;

  1208.     int nb_index_entries, i;

  1209.     AVStream *st;

  1210.     AVIStream *ast;

  1211.     unsigned int index, tag, flags, pos, len, first_packet = 1;

  1212.     unsigned last_pos= -1;

  1213.     int64_t idx1_pos, first_packet_pos = 0, data_offset = 0;

  1214. 

  1215.     nb_index_entries = size / 16;

  1216.     if (nb_index_entries <= 0)

  1217.         return -1;

  1218. 

  1219.     idx1_pos = avio_tell(pb);

  1220.     avio_seek(pb, avi->movi_list+4, SEEK_SET);

  1221.     if (avi_sync(s, 1) == 0) {

  1222.         first_packet_pos = avio_tell(pb) - 8;

  1223.     }

  1224.     avi->stream_index = -1;

  1225.     avio_seek(pb, idx1_pos, SEEK_SET);

  1226. 

  1227.     /* Read the entries and sort them in each stream component. */

  1228.     for(i = 0; i < nb_index_entries; i++) {

  1229.         tag = avio_rl32(pb);

  1230.         flags = avio_rl32(pb);

  1231.         pos = avio_rl32(pb);

  1232.         len = avio_rl32(pb);

  1233.         av_dlog(s, "%d: tag=0x%x flags=0x%x pos=0x%x len=%d/",

  1234.                 i, tag, flags, pos, len);

  1235. 

  1236.         index = ((tag & 0xff) - '0') * 10;

  1237.         index += ((tag >> 8) & 0xff) - '0';

  1238.         if (index >= s->nb_streams)

  1239.             continue;

  1240.         st = s->streams[index];

  1241.         ast = st->priv_data;

  1242. 

  1243.         if(first_packet && first_packet_pos && len) {

  1244.             data_offset = first_packet_pos - pos;

  1245.             first_packet = 0;

  1246.         }

  1247.         pos += data_offset;

  1248. 

  1249.         av_dlog(s, "%d cum_len=%"PRId64"\n", len, ast->cum_len);

  1250. 

  1251.         if(url_feof(pb))

  1252.             return -1;

  1253. 

  1254.         if(last_pos == pos)

  1255.             avi->non_interleaved= 1;

  1256.         else if(len || !ast->sample_size)

  1257.             av_add_index_entry(st, pos, ast->cum_len, len, 0, (flags&AVIIF_INDEX) ? AVINDEX_KEYFRAME : 0);

  1258.         ast->cum_len += get_duration(ast, len);

  1259.         last_pos= pos;

  1260.     }

  1261.     return 0;

  1262. }

  1263. 

  1264. static int guess_ni_flag(AVFormatContext *s){

  1265.     int i;

  1266.     int64_t last_start=0;

  1267.     int64_t first_end= INT64_MAX;

  1268.     int64_t oldpos= avio_tell(s->pb);

  1269. 

  1270.     for(i=0; i<s->nb_streams; i++){

  1271.         AVStream *st = s->streams[i];

  1272.         int n= st->nb_index_entries;

  1273.         unsigned int size;

  1274. 

  1275.         if(n <= 0)

  1276.             continue;

  1277. 

  1278.         if(n >= 2){

  1279.             int64_t pos= st->index_entries[0].pos;

  1280.             avio_seek(s->pb, pos + 4, SEEK_SET);

  1281.             size= avio_rl32(s->pb);

  1282.             if(pos + size > st->index_entries[1].pos)

  1283.                 last_start= INT64_MAX;

  1284.         }

  1285. 

  1286.         if(st->index_entries[0].pos > last_start)

  1287.             last_start= st->index_entries[0].pos;

  1288.         if(st->index_entries[n-1].pos < first_end)

  1289.             first_end= st->index_entries[n-1].pos;

  1290.     }

  1291.     avio_seek(s->pb, oldpos, SEEK_SET);

  1292.     return last_start > first_end;

  1293. }

  1294. 

  1295. static int avi_load_index(AVFormatContext *s)

  1296. {

  1297.     AVIContext *avi = s->priv_data;

  1298.     AVIOContext *pb = s->pb;

  1299.     uint32_t tag, size;

  1300.     int64_t pos= avio_tell(pb);

  1301.     int ret = -1;

  1302. 

  1303.     if (avio_seek(pb, avi->movi_end, SEEK_SET) < 0)

  1304.         goto the_end; // maybe truncated file

  1305.     av_dlog(s, "movi_end=0x%"PRIx64"\n", avi->movi_end);

  1306.     for(;;) {

  1307.         if (url_feof(pb))

  1308.             break;

  1309.         tag = avio_rl32(pb);

  1310.         size = avio_rl32(pb);

  1311.         av_dlog(s, "tag=%c%c%c%c size=0x%x\n",

  1312.                  tag        & 0xff,

  1313.                 (tag >>  8) & 0xff,

  1314.                 (tag >> 16) & 0xff,

  1315.                 (tag >> 24) & 0xff,

  1316.                 size);

  1317. 

  1318.         if (tag == MKTAG('i', 'd', 'x', '1') &&

  1319.             avi_read_idx1(s, size) >= 0) {

  1320.             avi->index_loaded=2;

  1321.             ret = 0;

  1322.             break;

  1323.         }

  1324. 

  1325.         size += (size & 1);

  1326.         if (avio_skip(pb, size) < 0)

  1327.             break; // something is wrong here

  1328.     }

  1329.  the_end:

  1330.     avio_seek(pb, pos, SEEK_SET);

  1331.     return ret;

  1332. }

  1333. 

  1334. static void seek_subtitle(AVStream *st, AVStream *st2, int64_t timestamp)

  1335. {

  1336.     AVIStream *ast2 = st2->priv_data;

  1337.     int64_t ts2 = av_rescale_q(timestamp, st->time_base, st2->time_base);

  1338.     av_free_packet(&ast2->sub_pkt);

  1339.     if (avformat_seek_file(ast2->sub_ctx, 0, INT64_MIN, ts2, ts2, 0) >= 0 ||

  1340.         avformat_seek_file(ast2->sub_ctx, 0, ts2, ts2, INT64_MAX, 0) >= 0)

  1341.         av_read_packet(ast2->sub_ctx, &ast2->sub_pkt);

  1342. }

  1343. 

  1344. static int avi_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)

  1345. {

  1346.     AVIContext *avi = s->priv_data;

  1347.     AVStream *st;

  1348.     int i, index;

  1349.     int64_t pos, pos_min;

  1350.     AVIStream *ast;

  1351. 

  1352.     if (!avi->index_loaded) {

  1353.         /* we only load the index on demand */

  1354.         avi_load_index(s);

  1355.         avi->index_loaded |= 1;

  1356.     }

  1357.     assert(stream_index>= 0);

  1358. 

  1359.     st = s->streams[stream_index];

  1360.     ast= st->priv_data;

  1361.     index= av_index_search_timestamp(st, timestamp * FFMAX(ast->sample_size, 1), flags);

  1362.     if(index<0)

  1363.         return -1;

  1364. 

  1365.     /* find the position */

  1366.     pos = st->index_entries[index].pos;

  1367.     timestamp = st->index_entries[index].timestamp / FFMAX(ast->sample_size, 1);

  1368. 

  1369. //    av_log(s, AV_LOG_DEBUG, "XX %"PRId64" %d %"PRId64"\n", timestamp, index, st->index_entries[index].timestamp);

  1370. 

  1371.     if (CONFIG_DV_DEMUXER && avi->dv_demux) {

  1372.         /* One and only one real stream for DV in AVI, and it has video  */

  1373.         /* offsets. Calling with other stream indexes should have failed */

  1374.         /* the av_index_search_timestamp call above.                     */

  1375.         assert(stream_index == 0);

  1376. 

  1377.         if(avio_seek(s->pb, pos, SEEK_SET) < 0)

  1378.             return -1;

  1379. 

  1380.         /* Feed the DV video stream version of the timestamp to the */

  1381.         /* DV demux so it can synthesize correct timestamps.        */

  1382.         dv_offset_reset(avi->dv_demux, timestamp);

  1383. 

  1384.         avi->stream_index= -1;

  1385.         return 0;

  1386.     }

  1387. 

  1388.     pos_min= pos;

  1389.     for(i = 0; i < s->nb_streams; i++) {

  1390.         AVStream *st2 = s->streams[i];

  1391.         AVIStream *ast2 = st2->priv_data;

  1392. 

  1393.         ast2->packet_size=

  1394.         ast2->remaining= 0;

  1395. 

  1396.         if (ast2->sub_ctx) {

  1397.             seek_subtitle(st, st2, timestamp);

  1398.             continue;

  1399.         }

  1400. 

  1401.         if (st2->nb_index_entries <= 0)

  1402.             continue;

  1403. 

  1404. //        assert(st2->codec->block_align);

  1405.         assert((int64_t)st2->time_base.num*ast2->rate == (int64_t)st2->time_base.den*ast2->scale);

  1406.         index = av_index_search_timestamp(

  1407.                 st2,

  1408.                 av_rescale_q(timestamp, st->time_base, st2->time_base) * FFMAX(ast2->sample_size, 1),

  1409.                 flags | AVSEEK_FLAG_BACKWARD | (st2->codec->codec_type != AVMEDIA_TYPE_VIDEO ? AVSEEK_FLAG_ANY : 0));

  1410.         if(index<0)

  1411.             index=0;

  1412.         ast2->seek_pos= st2->index_entries[index].pos;

  1413.         pos_min= FFMIN(pos_min,ast2->seek_pos);

  1414.     }

  1415.     for(i = 0; i < s->nb_streams; i++) {

  1416.         AVStream *st2 = s->streams[i];

  1417.         AVIStream *ast2 = st2->priv_data;

  1418. 

  1419.         if (ast2->sub_ctx || st2->nb_index_entries <= 0)

  1420.             continue;

  1421. 

  1422.         index = av_index_search_timestamp(

  1423.                 st2,

  1424.                 av_rescale_q(timestamp, st->time_base, st2->time_base) * FFMAX(ast2->sample_size, 1),

  1425.                 flags | AVSEEK_FLAG_BACKWARD | (st2->codec->codec_type != AVMEDIA_TYPE_VIDEO ? AVSEEK_FLAG_ANY : 0));

  1426.         if(index<0)

  1427.             index=0;

  1428.         while(!avi->non_interleaved && index>0 && st2->index_entries[index-1].pos >= pos_min)

  1429.             index--;

  1430.         ast2->frame_offset = st2->index_entries[index].timestamp;

  1431.     }

  1432. 

  1433.     /* do the seek */

  1434.     if (avio_seek(s->pb, pos_min, SEEK_SET) < 0)

  1435.         return -1;

  1436.     avi->stream_index= -1;

  1437.     avi->dts_max= INT_MIN;

  1438.     return 0;

  1439. }

  1440. 

  1441. static int avi_read_close(AVFormatContext *s)

  1442. {

  1443.     int i;

  1444.     AVIContext *avi = s->priv_data;

  1445. 

  1446.     for(i=0;i<s->nb_streams;i++) {

  1447.         AVStream *st = s->streams[i];

  1448.         AVIStream *ast = st->priv_data;

  1449.         if (ast) {

  1450.             if (ast->sub_ctx) {

  1451.                 av_freep(&ast->sub_ctx->pb);

  1452.                 av_close_input_file(ast->sub_ctx);

  1453.             }

  1454.             av_free(ast->sub_buffer);

  1455.             av_free_packet(&ast->sub_pkt);

  1456.         }

  1457.     }

  1458. 

  1459.     av_free(avi->dv_demux);

  1460. 

  1461.     return 0;

  1462. }

  1463. 

  1464. static int avi_probe(AVProbeData *p)

  1465. {

  1466.     int i;

  1467. 

  1468.     /* check file header */

  1469.     for(i=0; avi_headers[i][0]; i++)

  1470.         if(!memcmp(p->buf  , avi_headers[i]  , 4) &&

  1471.            !memcmp(p->buf+8, avi_headers[i]+4, 4))

  1472.             return AVPROBE_SCORE_MAX;

  1473. 

  1474.     return 0;

  1475. }

  1476. 

  1477. AVInputFormat ff_avi_demuxer = {

  1478.     .name           = "avi",

  1479.     .long_name      = NULL_IF_CONFIG_SMALL("AVI format"),

  1480.     .priv_data_size = sizeof(AVIContext),

  1481.     .read_probe     = avi_probe,

  1482.     .read_header    = avi_read_header,

  1483.     .read_packet    = avi_read_packet,

  1484.     .read_close     = avi_read_close,

  1485.     .read_seek      = avi_read_seek,

  1486.     .priv_class = &demuxer_class,

  1487. };