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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 "internal.h"

  30. #include "avi.h"

  31. #include "dv.h"

  32. #include "riff.h"

  33. 

  34. #undef NDEBUG

  35. #include <assert.h>

  36. 

  37. typedef struct AVIStream {

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

  39.                          (used to compute the pts) */

  40.     int remaining;

  41.     int packet_size;

  42. 

  43.     uint32_t scale;

  44.     uint32_t rate;

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

  46. 

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

  48. 

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

  50.     int prefix_count;

  51.     uint32_t pal[256];

  52.     int has_pal;

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

  54. 

  55.     AVFormatContext *sub_ctx;

  56.     AVPacket sub_pkt;

  57.     uint8_t *sub_buffer;

  58. 

  59.     int64_t seek_pos;

  60. } AVIStream;

  61. 

  62. typedef struct {

  63.     const AVClass *class;

  64.     int64_t  riff_end;

  65.     int64_t  movi_end;

  66.     int64_t  fsize;

  67.     int64_t movi_list;

  68.     int64_t last_pkt_pos;

  69.     int index_loaded;

  70.     int is_odml;

  71.     int non_interleaved;

  72.     int stream_index;

  73.     DVDemuxContext* dv_demux;

  74.     int odml_depth;

  75.     int use_odml;

  76. #define MAX_ODML_DEPTH 1000

  77.     int64_t dts_max;

  78. } AVIContext;

  79. 

  80. 

  81. static const AVOption options[] = {

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

  83.     { NULL },

  84. };

  85. 

  86. static const AVClass demuxer_class = {

  87.     .class_name = "avi",

  88.     .item_name  = av_default_item_name,

  89.     .option     = options,

  90.     .version    = LIBAVUTIL_VERSION_INT,

  91.     .category   = AV_CLASS_CATEGORY_DEMUXER,

  92. };

  93. 

  94. 

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

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

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

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

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

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

  101.     { 0 }

  102. };

  103. 

  104. static const AVMetadataConv avi_metadata_conv[] = {

  105.     { "strn", "title" },

  106.     { 0 },

  107. };

  108. 

  109. static int avi_load_index(AVFormatContext *s);

  110. static int guess_ni_flag(AVFormatContext *s);

  111. 

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

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

  114.            str, tag & 0xff,                             \

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

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

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

  118.            size)

  119. 

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

  121.     if(ast->sample_size){

  122.         return len;

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

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

  125.     }else

  126.         return 1;

  127. }

  128. 

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

  130. {

  131.     AVIContext *avi = s->priv_data;

  132.     char header[8];

  133.     int i;

  134. 

  135.     /* check RIFF header */

  136.     avio_read(pb, header, 4);

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

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

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

  140. 

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

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

  143.             break;

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

  145.         return -1;

  146. 

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

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

  149. 

  150.     return 0;

  151. }

  152. 

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

  154.     AVIContext *avi = s->priv_data;

  155.     AVIOContext *pb = s->pb;

  156.     int longs_pre_entry= avio_rl16(pb);

  157.     int index_sub_type = avio_r8(pb);

  158.     int index_type     = avio_r8(pb);

  159.     int entries_in_use = avio_rl32(pb);

  160.     int chunk_id       = avio_rl32(pb);

  161.     int64_t base       = avio_rl64(pb);

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

  163.     AVStream *st;

  164.     AVIStream *ast;

  165.     int i;

  166.     int64_t last_pos= -1;

  167.     int64_t filesize= avi->fsize;

  168. 

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

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

  171. 

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

  173.         return -1;

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

  175.     ast = st->priv_data;

  176. 

  177.     if(index_sub_type)

  178.         return -1;

  179. 

  180.     avio_rl32(pb);

  181. 

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

  183.         return -1;

  184.     if(index_type>1)

  185.         return -1;

  186. 

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

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

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

  190.             base &= 0xFFFFFFFF;

  191.         else

  192.             return -1;

  193.     }

  194. 

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

  196.         if(index_type){

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

  198.             int len    = avio_rl32(pb);

  199.             int key= len >= 0;

  200.             len &= 0x7FFFFFFF;

  201. 

  202. #ifdef DEBUG_SEEK

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

  204. #endif

  205.             if(url_feof(pb))

  206.                 return -1;

  207. 

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

  209.                 avi->non_interleaved= 1;

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

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

  212. 

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

  214.             last_pos= pos;

  215.         }else{

  216.             int64_t offset, pos;

  217.             int duration;

  218.             offset = avio_rl64(pb);

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

  220.             duration = avio_rl32(pb);

  221. 

  222.             if(url_feof(pb))

  223.                 return -1;

  224. 

  225.             pos = avio_tell(pb);

  226. 

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

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

  229.                 return -1;

  230.             }

  231. 

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

  233.                 return -1;

  234.             avi->odml_depth++;

  235.             read_braindead_odml_indx(s, frame_num);

  236.             avi->odml_depth--;

  237.             frame_num += duration;

  238. 

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

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

  241.                 return -1;

  242.             }

  243. 

  244.         }

  245.     }

  246.     avi->index_loaded=2;

  247.     return 0;

  248. }

  249. 

  250. static void clean_index(AVFormatContext *s){

  251.     int i;

  252.     int64_t j;

  253. 

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

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

  256.         AVIStream *ast = st->priv_data;

  257.         int n= st->nb_index_entries;

  258.         int max= ast->sample_size;

  259.         int64_t pos, size, ts;

  260. 

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

  262.             continue;

  263. 

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

  265. 

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

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

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

  269. 

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

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

  272.         }

  273.     }

  274. }

  275. 

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

  277. {

  278.     AVIOContext *pb = s->pb;

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

  280. 

  281.     size += (size & 1);

  282. 

  283.     if (size == UINT_MAX)

  284.         return -1;

  285.     value = av_malloc(size+1);

  286.     if (!value)

  287.         return -1;

  288.     avio_read(pb, value, size);

  289.     value[size]=0;

  290. 

  291.     AV_WL32(key, tag);

  292. 

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

  294.                             AV_DICT_DONT_STRDUP_VAL);

  295. }

  296. 

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

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

  299. 

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

  301. {

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

  303.     int i, day, year;

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

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

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

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

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

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

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

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

  312.             }

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

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

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

  316.     }

  317. }

  318. 

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

  320. {

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

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

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

  324.         switch (tag) {

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

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

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

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

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

  330.                 const char *name = NULL;

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

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

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

  334.                 switch (tag) {

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

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

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

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

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

  340.                     break;

  341.                 }

  342.                 if (name)

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

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

  345.             }

  346.             break;

  347.         }

  348.         default:

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

  350.             break;

  351.         }

  352.     }

  353. }

  354. 

  355. static int avi_read_header(AVFormatContext *s)

  356. {

  357.     AVIContext *avi = s->priv_data;

  358.     AVIOContext *pb = s->pb;

  359.     unsigned int tag, tag1, handler;

  360.     int codec_type, stream_index, frame_period;

  361.     unsigned int size;

  362.     int i;

  363.     AVStream *st;

  364.     AVIStream *ast = NULL;

  365.     int avih_width=0, avih_height=0;

  366.     int amv_file_format=0;

  367.     uint64_t list_end = 0;

  368.     int ret;

  369. 

  370.     avi->stream_index= -1;

  371. 

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

  373.         return -1;

  374. 

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

  376. 

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

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

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

  380. 

  381.     /* first list tag */

  382.     stream_index = -1;

  383.     codec_type = -1;

  384.     frame_period = 0;

  385.     for(;;) {

  386.         if (url_feof(pb))

  387.             goto fail;

  388.         tag = avio_rl32(pb);

  389.         size = avio_rl32(pb);

  390. 

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

  392. 

  393.         switch(tag) {

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

  395.             list_end = avio_tell(pb) + size;

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

  397.             tag1 = avio_rl32(pb);

  398. 

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

  400. 

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

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

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

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

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

  406.                 goto end_of_header;

  407.             }

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

  409.                 ff_read_riff_info(s, size - 4);

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

  411.                 avi_read_nikon(s, list_end);

  412. 

  413.             break;

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

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

  416.             size += (size & 1);

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

  418.             avio_skip(pb, size);

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

  420.             break;

  421.         }

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

  423.             avi->is_odml = 1;

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

  425.             break;

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

  427.             amv_file_format=1;

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

  429.             /* AVI header */

  430.             /* using frame_period is bad idea */

  431.             frame_period = avio_rl32(pb);

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

  433.             avio_rl32(pb);

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

  435. 

  436.             avio_skip(pb, 2 * 4);

  437.             avio_rl32(pb);

  438.             avio_rl32(pb);

  439.             avih_width=avio_rl32(pb);

  440.             avih_height=avio_rl32(pb);

  441. 

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

  443.             break;

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

  445.             /* stream header */

  446. 

  447.             tag1 = avio_rl32(pb);

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

  449. 

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

  451.                 avio_skip(pb, size - 8);

  452.                 break;

  453.             }else{

  454.                 stream_index++;

  455.                 st = avformat_new_stream(s, NULL);

  456.                 if (!st)

  457.                     goto fail;

  458. 

  459.                 st->id = stream_index;

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

  461.                 if (!ast)

  462.                     goto fail;

  463.                 st->priv_data = ast;

  464.             }

  465.             if(amv_file_format)

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

  467. 

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

  469. 

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

  471.                 int64_t dv_dur;

  472. 

  473.                 /*

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

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

  476.                  */

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

  478.                     goto fail;

  479. 

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

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

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

  483.                    goto fail;

  484. 

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

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

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

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

  489.                 s->nb_streams = 0;

  490.                 if (CONFIG_DV_DEMUXER) {

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

  492.                     if (!avi->dv_demux)

  493.                         goto fail;

  494.                 }

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

  496.                 avio_skip(pb, 3 * 4);

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

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

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

  500. 

  501.                 dv_dur = avio_rl32(pb);

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

  503.                     dv_dur *= AV_TIME_BASE;

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

  505.                 }

  506.                 /*

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

  508.                  *      will make a guess based on bitrate.

  509.                  */

  510. 

  511.                 stream_index = s->nb_streams - 1;

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

  513.                 break;

  514.             }

  515. 

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

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

  518. 

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

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

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

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

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

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

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

  526.                 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);

  527.                 if(frame_period){

  528.                     ast->rate = 1000000;

  529.                     ast->scale = frame_period;

  530.                 }else{

  531.                     ast->rate = 25;

  532.                     ast->scale = 1;

  533.                 }

  534.             }

  535.             avpriv_set_pts_info(st, 64, ast->scale, ast->rate);

  536. 

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

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

  539. 

  540.             st->start_time = 0;

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

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

  543.             if (ast->cum_len*ast->scale/ast->rate > 3600) {

  544.                 av_log(s, AV_LOG_ERROR, "crazy start time, iam scared, giving up\n");

  545.                 return AVERROR_INVALIDDATA;

  546.             }

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

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

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

  550. 

  551.             switch(tag1) {

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

  553.                 codec_type = AVMEDIA_TYPE_VIDEO;

  554. 

  555.                 ast->sample_size = 0;

  556.                 break;

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

  558.                 codec_type = AVMEDIA_TYPE_AUDIO;

  559.                 break;

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

  561.                 codec_type = AVMEDIA_TYPE_SUBTITLE;

  562.                 break;

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

  564.                 codec_type = AVMEDIA_TYPE_DATA;

  565.                 break;

  566.             default:

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

  568.             }

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

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

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

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

  573.             break;

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

  575.             /* stream header */

  576.             if (!size)

  577.                 break;

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

  579.                 avio_skip(pb, size);

  580.             } else {

  581.                 uint64_t cur_pos = avio_tell(pb);

  582.                 unsigned esize;

  583.                 if (cur_pos < list_end)

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

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

  586.                 switch(codec_type) {

  587.                 case AVMEDIA_TYPE_VIDEO:

  588.                     if(amv_file_format){

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

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

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

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

  593.                         avio_skip(pb, size);

  594.                         break;

  595.                     }

  596.                     tag1 = ff_get_bmp_header(pb, st, &esize);

  597. 

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

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

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

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

  602.                         break;

  603.                     }

  604. 

  605.                     if(size > 10*4 && size<(1<<30) && size < avi->fsize){

  606.                         if(esize == size-1 && (esize&1)) st->codec->extradata_size= esize - 10*4;

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

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

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

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

  611.                             return AVERROR(ENOMEM);

  612.                         }

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

  614.                     }

  615. 

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

  617.                         avio_r8(pb);

  618. 

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

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

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

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

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

  624.                         const uint8_t *pal_src;

  625. 

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

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

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

  629.                             ast->pal[i] = 0xFF<<24 | AV_RL32(pal_src+4*i);

  630.                         ast->has_pal = 1;

  631.                     }

  632. 

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

  634. 

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

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

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

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

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

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

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

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

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

  644. 

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

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

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

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

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

  650.                     }

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

  652. 

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

  654.                     break;

  655.                 case AVMEDIA_TYPE_AUDIO:

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

  657.                     if (ret < 0)

  658.                         return ret;

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

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

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

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

  663.                     }

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

  665.                         avio_skip(pb, 1);

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

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

  668.                     st->need_parsing = AVSTREAM_PARSE_TIMESTAMPS;

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

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

  671.                      * fail. */

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

  673.                         st->need_parsing = AVSTREAM_PARSE_NONE;

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

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

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

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

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

  679.                         ast->dshow_block_align = 0;

  680.                     }

  681.                     if (amv_file_format){

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

  683.                         ast->dshow_block_align = 0;

  684.                     }

  685.                     break;

  686.                 case AVMEDIA_TYPE_SUBTITLE:

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

  688.                     st->request_probe= 1;

  689.                     break;

  690.                 default:

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

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

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

  694.                     avio_skip(pb, size);

  695.                     break;

  696.                 }

  697.             }

  698.             break;

  699.         case MKTAG('s', 't', 'r', 'd'):

  700.             if (stream_index >= (unsigned)s->nb_streams || s->streams[stream_index]->codec->extradata_size) {

  701.                 avio_skip(pb, size);

  702.             } else {

  703.                 uint64_t cur_pos = avio_tell(pb);

  704.                 if (cur_pos < list_end)

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

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

  707. 

  708.                 if(size<(1<<30)){

  709.                     st->codec->extradata_size= size;

  710.                     st->codec->extradata= av_mallocz(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);

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

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

  713.                         return AVERROR(ENOMEM);

  714.                     }

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

  716.                 }

  717. 

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

  719.                     avio_r8(pb);

  720.             }

  721.             break;

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

  723.             i= avio_tell(pb);

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

  725.                read_braindead_odml_indx(s, 0) < 0 && (s->error_recognition & AV_EF_EXPLODE))

  726.                 goto fail;

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

  728.             break;

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

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

  731.                 AVRational active, active_aspect;

  732. 

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

  734.                 avio_rl32(pb);

  735.                 avio_rl32(pb);

  736.                 avio_rl32(pb);

  737.                 avio_rl32(pb);

  738.                 avio_rl32(pb);

  739. 

  740.                 active_aspect.den= avio_rl16(pb);

  741.                 active_aspect.num= avio_rl16(pb);

  742.                 active.num       = avio_rl32(pb);

  743.                 active.den       = avio_rl32(pb);

  744.                 avio_rl32(pb); //nbFieldsPerFrame

  745. 

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

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

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

  749.                 }

  750.                 size -= 9*4;

  751.             }

  752.             avio_skip(pb, size);

  753.             break;

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

  755.             if(s->nb_streams){

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

  757.                 break;

  758.             }

  759.         default:

  760.             if(size > 1000000){

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

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

  763.                 if (s->error_recognition & AV_EF_EXPLODE)

  764.                     goto fail;

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

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

  767.                 goto end_of_header;

  768.             }

  769.             /* skip tag */

  770.             size += (size & 1);

  771.             avio_skip(pb, size);

  772.             break;

  773.         }

  774.     }

  775.  end_of_header:

  776.     /* check stream number */

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

  778.     fail:

  779.         return -1;

  780.     }

  781. 

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

  783.         avi_load_index(s);

  784.     avi->index_loaded |= 1;

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

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

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

  788.         if(st->nb_index_entries)

  789.             break;

  790.     }

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

  792.     // a mis-detection.

  793.     if(avi->dv_demux)

  794.         avi->non_interleaved=0;

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

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

  797.         avi->non_interleaved=0;

  798.     }

  799. 

  800.     if(avi->non_interleaved) {

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

  802.         clean_index(s);

  803.     }

  804. 

  805.     ff_metadata_conv_ctx(s, NULL, avi_metadata_conv);

  806.     ff_metadata_conv_ctx(s, NULL, ff_riff_info_conv);

  807. 

  808.     return 0;

  809. }

  810. 

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

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

  813.         uint8_t desc[256];

  814.         int score = AVPROBE_SCORE_MAX / 2, ret;

  815.         AVIStream *ast = st->priv_data;

  816.         AVInputFormat *sub_demuxer;

  817.         AVRational time_base;

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

  819.                                               pkt->size - 7,

  820.                                               0, NULL, NULL, NULL, NULL);

  821.         AVProbeData pd;

  822.         unsigned int desc_len = avio_rl32(pb);

  823. 

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

  825.             goto error;

  826. 

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

  828.         avio_skip(pb, desc_len - ret);

  829.         if (*desc)

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

  831. 

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

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

  834. 

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

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

  837.             goto error;

  838. 

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

  840.             goto error;

  841. 

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

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

  844.             ff_read_packet(ast->sub_ctx, &ast->sub_pkt);

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

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

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

  848.             avpriv_set_pts_info(st, 64, time_base.num, time_base.den);

  849.         }

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

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

  852.         return 1;

  853. error:

  854.         av_freep(&pb);

  855.     }

  856.     return 0;

  857. }

  858. 

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

  860.                                   AVPacket *pkt)

  861. {

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

  863.     int64_t ts, next_ts, ts_min = INT64_MAX;

  864.     AVStream *st, *sub_st = NULL;

  865.     int i;

  866. 

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

  868.                            AV_TIME_BASE_Q);

  869. 

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

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

  872.         ast = st->priv_data;

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

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

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

  876.                 ts_min = ts;

  877.                 sub_st = st;

  878.             }

  879.         }

  880.     }

  881. 

  882.     if (sub_st) {

  883.         ast = sub_st->priv_data;

  884.         *pkt = ast->sub_pkt;

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

  886.         if (ff_read_packet(ast->sub_ctx, &ast->sub_pkt) < 0)

  887.             ast->sub_pkt.data = NULL;

  888.     }

  889.     return sub_st;

  890. }

  891. 

  892. static int get_stream_idx(int *d){

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

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

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

  896.     }else{

  897.         return 100; //invalid stream ID

  898.     }

  899. }

  900. 

  901. /**

  902.  *

  903.  * @param exit_early set to 1 to just gather packet position without making the changes needed to actually read & return the packet

  904.  */

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

  906. {

  907.     AVIContext *avi = s->priv_data;

  908.     AVIOContext *pb = s->pb;

  909.     int n;

  910.     unsigned int d[8];

  911.     unsigned int size;

  912.     int64_t i, sync;

  913. 

  914. start_sync:

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

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

  917.         int j;

  918. 

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

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

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

  922. 

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

  924. 

  925.         n= get_stream_idx(d+2);

  926. //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);

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

  928.             continue;

  929. 

  930.         //parse ix##

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

  932.         //parse JUNK

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

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

  935.             avio_skip(pb, size);

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

  937.             goto start_sync;

  938.         }

  939. 

  940.         //parse stray LIST

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

  942.             avio_skip(pb, 4);

  943.             goto start_sync;

  944.         }

  945. 

  946.         n= get_stream_idx(d);

  947. 

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

  949.             continue;

  950. 

  951.         //detect ##ix chunk and skip

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

  953.             avio_skip(pb, size);

  954.             goto start_sync;

  955.         }

  956. 

  957.         //parse ##dc/##wb

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

  959.             AVStream *st;

  960.             AVIStream *ast;

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

  962.             ast = st->priv_data;

  963. 

  964.             if (!ast) {

  965.                 av_log(s, AV_LOG_WARNING, "Skiping foreign stream %d packet\n", n);

  966.                 continue;

  967.             }

  968. 

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

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

  971.                 AVIStream *ast1= st1->priv_data;

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

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

  974.                    && n==0

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

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

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

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

  979.                   ){

  980.                     n=1;

  981.                     st = st1;

  982.                     ast = ast1;

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

  984.                 }

  985.             }

  986. 

  987. 

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

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

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

  991.                 if (!exit_early) {

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

  993.                 }

  994.                 avio_skip(pb, size);

  995.                 goto start_sync;

  996.             }

  997. 

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

  999.                 int k = avio_r8(pb);

  1000.                 int last = (k + avio_r8(pb) - 1) & 0xFF;

  1001. 

  1002.                 avio_rl16(pb); //flags

  1003. 

  1004.                 for (; k <= last; k++)

  1005.                     ast->pal[k] = 0xFF<<24 | avio_rb32(pb)>>8;// b + (g << 8) + (r << 16);

  1006.                 ast->has_pal= 1;

  1007.                 goto start_sync;

  1008.             } else if(   ((ast->prefix_count<5 || sync+9 > i) && d[2]<128 && d[3]<128) ||

  1009.                          d[2]*256+d[3] == ast->prefix /*||

  1010.                          (d[2] == 'd' && d[3] == 'c') ||

  1011.                          (d[2] == 'w' && d[3] == 'b')*/) {

  1012. 

  1013.                 if (exit_early)

  1014.                     return 0;

  1015. //av_log(s, AV_LOG_DEBUG, "OK\n");

  1016.                 if(d[2]*256+d[3] == ast->prefix)

  1017.                     ast->prefix_count++;

  1018.                 else{

  1019.                     ast->prefix= d[2]*256+d[3];

  1020.                     ast->prefix_count= 0;

  1021.                 }

  1022. 

  1023.                 avi->stream_index= n;

  1024.                 ast->packet_size= size + 8;

  1025.                 ast->remaining= size;

  1026. 

  1027.                 if(size || !ast->sample_size){

  1028.                     uint64_t pos= avio_tell(pb) - 8;

  1029.                     if(!st->index_entries || !st->nb_index_entries || st->index_entries[st->nb_index_entries - 1].pos < pos){

  1030.                         av_add_index_entry(st, pos, ast->frame_offset, size, 0, AVINDEX_KEYFRAME);

  1031.                     }

  1032.                 }

  1033.                 return 0;

  1034.             }

  1035.         }

  1036.     }

  1037. 

  1038.     if(pb->error)

  1039.         return pb->error;

  1040.     return AVERROR_EOF;

  1041. }

  1042. 

  1043. static int avi_read_packet(AVFormatContext *s, AVPacket *pkt)

  1044. {

  1045.     AVIContext *avi = s->priv_data;

  1046.     AVIOContext *pb = s->pb;

  1047.     int err;

  1048.     void* dstr;

  1049. 

  1050.     if (CONFIG_DV_DEMUXER && avi->dv_demux) {

  1051.         int size = avpriv_dv_get_packet(avi->dv_demux, pkt);

  1052.         if (size >= 0)

  1053.             return size;

  1054.     }

  1055. 

  1056.     if(avi->non_interleaved){

  1057.         int best_stream_index = 0;

  1058.         AVStream *best_st= NULL;

  1059.         AVIStream *best_ast;

  1060.         int64_t best_ts= INT64_MAX;

  1061.         int i;

  1062. 

  1063.         for(i=0; i<s->nb_streams; i++){

  1064.             AVStream *st = s->streams[i];

  1065.             AVIStream *ast = st->priv_data;

  1066.             int64_t ts= ast->frame_offset;

  1067.             int64_t last_ts;

  1068. 

  1069.             if(!st->nb_index_entries)

  1070.                 continue;

  1071. 

  1072.             last_ts = st->index_entries[st->nb_index_entries - 1].timestamp;

  1073.             if(!ast->remaining && ts > last_ts)

  1074.                 continue;

  1075. 

  1076.             ts = av_rescale_q(ts, st->time_base, (AVRational){FFMAX(1, ast->sample_size), AV_TIME_BASE});

  1077. 

  1078. //            av_log(s, AV_LOG_DEBUG, "%"PRId64" %d/%d %"PRId64"\n", ts, st->time_base.num, st->time_base.den, ast->frame_offset);

  1079.             if(ts < best_ts){

  1080.                 best_ts= ts;

  1081.                 best_st= st;

  1082.                 best_stream_index= i;

  1083.             }

  1084.         }

  1085.         if(!best_st)

  1086.             return AVERROR_EOF;

  1087. 

  1088.         best_ast = best_st->priv_data;

  1089.         best_ts = best_ast->frame_offset;

  1090.         if(best_ast->remaining)

  1091.             i= av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY | AVSEEK_FLAG_BACKWARD);

  1092.         else{

  1093.             i= av_index_search_timestamp(best_st, best_ts, AVSEEK_FLAG_ANY);

  1094.             if(i>=0)

  1095.                 best_ast->frame_offset= best_st->index_entries[i].timestamp;

  1096.         }

  1097. 

  1098. //        av_log(s, AV_LOG_DEBUG, "%d\n", i);

  1099.         if(i>=0){

  1100.             int64_t pos= best_st->index_entries[i].pos;

  1101.             pos += best_ast->packet_size - best_ast->remaining;

  1102.             if(avio_seek(s->pb, pos + 8, SEEK_SET) < 0)

  1103.               return AVERROR_EOF;

  1104. //        av_log(s, AV_LOG_DEBUG, "pos=%"PRId64"\n", pos);

  1105. 

  1106.             assert(best_ast->remaining <= best_ast->packet_size);

  1107. 

  1108.             avi->stream_index= best_stream_index;

  1109.             if(!best_ast->remaining)

  1110.                 best_ast->packet_size=

  1111.                 best_ast->remaining= best_st->index_entries[i].size;

  1112.         }

  1113.         else

  1114.           return AVERROR_EOF;

  1115.     }

  1116. 

  1117. resync:

  1118.     if(avi->stream_index >= 0){

  1119.         AVStream *st= s->streams[ avi->stream_index ];

  1120.         AVIStream *ast= st->priv_data;

  1121.         int size, err;

  1122. 

  1123.         if(get_subtitle_pkt(s, st, pkt))

  1124.             return 0;

  1125. 

  1126.         if(ast->sample_size <= 1) // minorityreport.AVI block_align=1024 sample_size=1 IMA-ADPCM

  1127.             size= INT_MAX;

  1128.         else if(ast->sample_size < 32)

  1129.             // arbitrary multiplier to avoid tiny packets for raw PCM data

  1130.             size= 1024*ast->sample_size;

  1131.         else

  1132.             size= ast->sample_size;

  1133. 

  1134.         if(size > ast->remaining)

  1135.             size= ast->remaining;

  1136.         avi->last_pkt_pos= avio_tell(pb);

  1137.         err= av_get_packet(pb, pkt, size);

  1138.         if(err<0)

  1139.             return err;

  1140.         size = err;

  1141. 

  1142.         if(ast->has_pal && pkt->data && pkt->size<(unsigned)INT_MAX/2){

  1143.             uint8_t *pal;

  1144.             pal = av_packet_new_side_data(pkt, AV_PKT_DATA_PALETTE, AVPALETTE_SIZE);

  1145.             if(!pal){

  1146.                 av_log(s, AV_LOG_ERROR, "Failed to allocate data for palette\n");

  1147.             }else{

  1148.                 memcpy(pal, ast->pal, AVPALETTE_SIZE);

  1149.                 ast->has_pal = 0;

  1150.             }

  1151.         }

  1152. 

  1153.         if (CONFIG_DV_DEMUXER && avi->dv_demux) {

  1154.             dstr = pkt->destruct;

  1155.             size = avpriv_dv_produce_packet(avi->dv_demux, pkt,

  1156.                                     pkt->data, pkt->size, pkt->pos);

  1157.             pkt->destruct = dstr;

  1158.             pkt->flags |= AV_PKT_FLAG_KEY;

  1159.             if (size < 0)

  1160.                 av_free_packet(pkt);

  1161.         } else if (st->codec->codec_type == AVMEDIA_TYPE_SUBTITLE

  1162.                    && !st->codec->codec_tag && read_gab2_sub(st, pkt)) {

  1163.             ast->frame_offset++;

  1164.             avi->stream_index = -1;

  1165.             ast->remaining = 0;

  1166.             goto resync;

  1167.         } else {

  1168.             /* XXX: How to handle B-frames in AVI? */

  1169.             pkt->dts = ast->frame_offset;

  1170. //                pkt->dts += ast->start;

  1171.             if(ast->sample_size)

  1172.                 pkt->dts /= ast->sample_size;

  1173. //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);

  1174.             pkt->stream_index = avi->stream_index;

  1175. 

  1176.             if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {

  1177.                 AVIndexEntry *e;

  1178.                 int index;

  1179.                 assert(st->index_entries);

  1180. 

  1181.                 index= av_index_search_timestamp(st, ast->frame_offset, 0);

  1182.                 e= &st->index_entries[index];

  1183. 

  1184.                 if(index >= 0 && e->timestamp == ast->frame_offset){

  1185.                     if (index == st->nb_index_entries-1){

  1186.                         int key=1;

  1187.                         int i;

  1188.                         uint32_t state=-1;

  1189.                         for(i=0; i<FFMIN(size,256); i++){

  1190.                             if(st->codec->codec_id == CODEC_ID_MPEG4){

  1191.                                 if(state == 0x1B6){

  1192.                                     key= !(pkt->data[i]&0xC0);

  1193.                                     break;

  1194.                                 }

  1195.                             }else

  1196.                                 break;

  1197.                             state= (state<<8) + pkt->data[i];

  1198.                         }

  1199.                         if(!key)

  1200.                             e->flags &= ~AVINDEX_KEYFRAME;

  1201.                     }

  1202.                     if (e->flags & AVINDEX_KEYFRAME)

  1203.                         pkt->flags |= AV_PKT_FLAG_KEY;

  1204.                 }

  1205.             } else {

  1206.                 pkt->flags |= AV_PKT_FLAG_KEY;

  1207.             }

  1208.             ast->frame_offset += get_duration(ast, pkt->size);

  1209.         }

  1210.         ast->remaining -= size;

  1211.         if(!ast->remaining){

  1212.             avi->stream_index= -1;

  1213.             ast->packet_size= 0;

  1214.         }

  1215. 

  1216.         if(!avi->non_interleaved && pkt->pos >= 0 && ast->seek_pos > pkt->pos){

  1217.             av_free_packet(pkt);

  1218.             goto resync;

  1219.         }

  1220.         ast->seek_pos= 0;

  1221. 

  1222.         if(!avi->non_interleaved && st->nb_index_entries>1 && avi->index_loaded>1){

  1223.             int64_t dts= av_rescale_q(pkt->dts, st->time_base, AV_TIME_BASE_Q);

  1224. 

  1225.             if(avi->dts_max - dts > 2*AV_TIME_BASE){

  1226.                 avi->non_interleaved= 1;

  1227.                 av_log(s, AV_LOG_INFO, "Switching to NI mode, due to poor interleaving\n");

  1228.             }else if(avi->dts_max < dts)

  1229.                 avi->dts_max = dts;

  1230.         }

  1231. 

  1232.         return size;

  1233.     }

  1234. 

  1235.     if ((err = avi_sync(s, 0)) < 0)

  1236.         return err;

  1237.     goto resync;

  1238. }

  1239. 

  1240. /* XXX: We make the implicit supposition that the positions are sorted

  1241.    for each stream. */

  1242. static int avi_read_idx1(AVFormatContext *s, int size)

  1243. {

  1244.     AVIContext *avi = s->priv_data;

  1245.     AVIOContext *pb = s->pb;

  1246.     int nb_index_entries, i;

  1247.     AVStream *st;

  1248.     AVIStream *ast;

  1249.     unsigned int index, tag, flags, pos, len, first_packet = 1;

  1250.     unsigned last_pos= -1;

  1251.     unsigned last_idx= -1;

  1252.     int64_t idx1_pos, first_packet_pos = 0, data_offset = 0;

  1253. 

  1254.     nb_index_entries = size / 16;

  1255.     if (nb_index_entries <= 0)

  1256.         return -1;

  1257. 

  1258.     idx1_pos = avio_tell(pb);

  1259.     avio_seek(pb, avi->movi_list+4, SEEK_SET);

  1260.     if (avi_sync(s, 1) == 0) {

  1261.         first_packet_pos = avio_tell(pb) - 8;

  1262.     }

  1263.     avi->stream_index = -1;

  1264.     avio_seek(pb, idx1_pos, SEEK_SET);

  1265. 

  1266.     /* Read the entries and sort them in each stream component. */

  1267.     for(i = 0; i < nb_index_entries; i++) {

  1268.         if(url_feof(pb))

  1269.             return -1;

  1270. 

  1271.         tag = avio_rl32(pb);

  1272.         flags = avio_rl32(pb);

  1273.         pos = avio_rl32(pb);

  1274.         len = avio_rl32(pb);

  1275.         av_dlog(s, "%d: tag=0x%x flags=0x%x pos=0x%x len=%d/",

  1276.                 i, tag, flags, pos, len);

  1277. 

  1278.         index = ((tag & 0xff) - '0') * 10;

  1279.         index += ((tag >> 8) & 0xff) - '0';

  1280.         if (index >= s->nb_streams)

  1281.             continue;

  1282.         st = s->streams[index];

  1283.         ast = st->priv_data;

  1284. 

  1285.         if(first_packet && first_packet_pos && len) {

  1286.             data_offset = first_packet_pos - pos;

  1287.             first_packet = 0;

  1288.         }

  1289.         pos += data_offset;

  1290. 

  1291.         av_dlog(s, "%d cum_len=%"PRId64"\n", len, ast->cum_len);

  1292. 

  1293. 

  1294.         // even if we have only a single stream, we should

  1295.         // switch to non-interleaved to get correct timestamps

  1296.         if(last_pos == pos)

  1297.             avi->non_interleaved= 1;

  1298.         if(last_idx != pos && len) {

  1299.             av_add_index_entry(st, pos, ast->cum_len, len, 0, (flags&AVIIF_INDEX) ? AVINDEX_KEYFRAME : 0);

  1300.             last_idx= pos;

  1301.         }

  1302.         ast->cum_len += get_duration(ast, len);

  1303.         last_pos= pos;

  1304.     }

  1305.     return 0;

  1306. }

  1307. 

  1308. static int guess_ni_flag(AVFormatContext *s){

  1309.     int i;

  1310.     int64_t last_start=0;

  1311.     int64_t first_end= INT64_MAX;

  1312.     int64_t oldpos= avio_tell(s->pb);

  1313.     int *idx;

  1314.     int64_t min_pos, pos;

  1315. 

  1316.     for(i=0; i<s->nb_streams; i++){

  1317.         AVStream *st = s->streams[i];

  1318.         int n= st->nb_index_entries;

  1319.         unsigned int size;

  1320. 

  1321.         if(n <= 0)

  1322.             continue;

  1323. 

  1324.         if(n >= 2){

  1325.             int64_t pos= st->index_entries[0].pos;

  1326.             avio_seek(s->pb, pos + 4, SEEK_SET);

  1327.             size= avio_rl32(s->pb);

  1328.             if(pos + size > st->index_entries[1].pos)

  1329.                 last_start= INT64_MAX;

  1330.         }

  1331. 

  1332.         if(st->index_entries[0].pos > last_start)

  1333.             last_start= st->index_entries[0].pos;

  1334.         if(st->index_entries[n-1].pos < first_end)

  1335.             first_end= st->index_entries[n-1].pos;

  1336.     }

  1337.     avio_seek(s->pb, oldpos, SEEK_SET);

  1338.     if (last_start > first_end)

  1339.         return 1;

  1340.     idx= av_mallocz(sizeof(*idx) * s->nb_streams);

  1341.     for (min_pos=pos=0; min_pos!=INT64_MAX; pos= min_pos+1) {

  1342.         int64_t max_dts = INT64_MIN/2, min_dts= INT64_MAX/2;

  1343.         min_pos = INT64_MAX;

  1344. 

  1345.         for (i=0; i<s->nb_streams; i++) {

  1346.             AVStream *st = s->streams[i];

  1347.             int n= st->nb_index_entries;

  1348.             while (idx[i]<n && st->index_entries[idx[i]].pos < pos)

  1349.                 idx[i]++;

  1350.             if (idx[i] < n) {

  1351.                 min_dts = FFMIN(min_dts, av_rescale_q(st->index_entries[idx[i]].timestamp, st->time_base, AV_TIME_BASE_Q));

  1352.                 min_pos = FFMIN(min_pos, st->index_entries[idx[i]].pos);

  1353.             }

  1354.             if (idx[i])

  1355.                 max_dts = FFMAX(max_dts, av_rescale_q(st->index_entries[idx[i]-1].timestamp, st->time_base, AV_TIME_BASE_Q));

  1356.         }

  1357.         if(max_dts - min_dts > 2*AV_TIME_BASE) {

  1358.             av_free(idx);

  1359.             return 1;

  1360.         }

  1361.     }

  1362.     av_free(idx);

  1363.     return 0;

  1364. }

  1365. 

  1366. static int avi_load_index(AVFormatContext *s)

  1367. {

  1368.     AVIContext *avi = s->priv_data;

  1369.     AVIOContext *pb = s->pb;

  1370.     uint32_t tag, size;

  1371.     int64_t pos= avio_tell(pb);

  1372.     int ret = -1;

  1373. 

  1374.     if (avio_seek(pb, avi->movi_end, SEEK_SET) < 0)

  1375.         goto the_end; // maybe truncated file

  1376.     av_dlog(s, "movi_end=0x%"PRIx64"\n", avi->movi_end);

  1377.     for(;;) {

  1378.         if (url_feof(pb))

  1379.             break;

  1380.         tag = avio_rl32(pb);

  1381.         size = avio_rl32(pb);

  1382.         av_dlog(s, "tag=%c%c%c%c size=0x%x\n",

  1383.                  tag        & 0xff,

  1384.                 (tag >>  8) & 0xff,

  1385.                 (tag >> 16) & 0xff,

  1386.                 (tag >> 24) & 0xff,

  1387.                 size);

  1388. 

  1389.         if (tag == MKTAG('i', 'd', 'x', '1') &&

  1390.             avi_read_idx1(s, size) >= 0) {

  1391.             avi->index_loaded=2;

  1392.             ret = 0;

  1393.             break;

  1394.         }

  1395. 

  1396.         size += (size & 1);

  1397.         if (avio_skip(pb, size) < 0)

  1398.             break; // something is wrong here

  1399.     }

  1400.  the_end:

  1401.     avio_seek(pb, pos, SEEK_SET);

  1402.     return ret;

  1403. }

  1404. 

  1405. static void seek_subtitle(AVStream *st, AVStream *st2, int64_t timestamp)

  1406. {

  1407.     AVIStream *ast2 = st2->priv_data;

  1408.     int64_t ts2 = av_rescale_q(timestamp, st->time_base, st2->time_base);

  1409.     av_free_packet(&ast2->sub_pkt);

  1410.     if (avformat_seek_file(ast2->sub_ctx, 0, INT64_MIN, ts2, ts2, 0) >= 0 ||

  1411.         avformat_seek_file(ast2->sub_ctx, 0, ts2, ts2, INT64_MAX, 0) >= 0)

  1412.         ff_read_packet(ast2->sub_ctx, &ast2->sub_pkt);

  1413. }

  1414. 

  1415. static int avi_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)

  1416. {

  1417.     AVIContext *avi = s->priv_data;

  1418.     AVStream *st;

  1419.     int i, index;

  1420.     int64_t pos, pos_min;

  1421.     AVIStream *ast;

  1422. 

  1423.     if (!avi->index_loaded) {

  1424.         /* we only load the index on demand */

  1425.         avi_load_index(s);

  1426.         avi->index_loaded |= 1;

  1427.     }

  1428.     assert(stream_index>= 0);

  1429. 

  1430.     st = s->streams[stream_index];

  1431.     ast= st->priv_data;

  1432.     index= av_index_search_timestamp(st, timestamp * FFMAX(ast->sample_size, 1), flags);

  1433.     if (index<0) {

  1434.         if (st->nb_index_entries > 0)

  1435.             av_log(s, AV_LOG_DEBUG, "Failed to find timestamp %"PRId64 " in index %"PRId64 " .. %"PRId64 "\n",

  1436.                    timestamp * FFMAX(ast->sample_size, 1),

  1437.                    st->index_entries[0].timestamp,

  1438.                    st->index_entries[st->nb_index_entries - 1].timestamp);

  1439.         return -1;

  1440.     }

  1441. 

  1442.     /* find the position */

  1443.     pos = st->index_entries[index].pos;

  1444.     timestamp = st->index_entries[index].timestamp / FFMAX(ast->sample_size, 1);

  1445. 

  1446. //    av_log(s, AV_LOG_DEBUG, "XX %"PRId64" %d %"PRId64"\n", timestamp, index, st->index_entries[index].timestamp);

  1447. 

  1448.     if (CONFIG_DV_DEMUXER && avi->dv_demux) {

  1449.         /* One and only one real stream for DV in AVI, and it has video  */

  1450.         /* offsets. Calling with other stream indexes should have failed */

  1451.         /* the av_index_search_timestamp call above.                     */

  1452.         assert(stream_index == 0);

  1453. 

  1454.         if(avio_seek(s->pb, pos, SEEK_SET) < 0)

  1455.             return -1;

  1456. 

  1457.         /* Feed the DV video stream version of the timestamp to the */

  1458.         /* DV demux so it can synthesize correct timestamps.        */

  1459.         ff_dv_offset_reset(avi->dv_demux, timestamp);

  1460. 

  1461.         avi->stream_index= -1;

  1462.         return 0;

  1463.     }

  1464. 

  1465.     pos_min= pos;

  1466.     for(i = 0; i < s->nb_streams; i++) {

  1467.         AVStream *st2 = s->streams[i];

  1468.         AVIStream *ast2 = st2->priv_data;

  1469. 

  1470.         ast2->packet_size=

  1471.         ast2->remaining= 0;

  1472. 

  1473.         if (ast2->sub_ctx) {

  1474.             seek_subtitle(st, st2, timestamp);

  1475.             continue;

  1476.         }

  1477. 

  1478.         if (st2->nb_index_entries <= 0)

  1479.             continue;

  1480. 

  1481. //        assert(st2->codec->block_align);

  1482.         assert((int64_t)st2->time_base.num*ast2->rate == (int64_t)st2->time_base.den*ast2->scale);

  1483.         index = av_index_search_timestamp(

  1484.                 st2,

  1485.                 av_rescale_q(timestamp, st->time_base, st2->time_base) * FFMAX(ast2->sample_size, 1),

  1486.                 flags | AVSEEK_FLAG_BACKWARD | (st2->codec->codec_type != AVMEDIA_TYPE_VIDEO ? AVSEEK_FLAG_ANY : 0));

  1487.         if(index<0)

  1488.             index=0;

  1489.         ast2->seek_pos= st2->index_entries[index].pos;

  1490.         pos_min= FFMIN(pos_min,ast2->seek_pos);

  1491.     }

  1492.     for(i = 0; i < s->nb_streams; i++) {

  1493.         AVStream *st2 = s->streams[i];

  1494.         AVIStream *ast2 = st2->priv_data;

  1495. 

  1496.         if (ast2->sub_ctx || st2->nb_index_entries <= 0)

  1497.             continue;

  1498. 

  1499.         index = av_index_search_timestamp(

  1500.                 st2,

  1501.                 av_rescale_q(timestamp, st->time_base, st2->time_base) * FFMAX(ast2->sample_size, 1),

  1502.                 flags | AVSEEK_FLAG_BACKWARD | (st2->codec->codec_type != AVMEDIA_TYPE_VIDEO ? AVSEEK_FLAG_ANY : 0));

  1503.         if(index<0)

  1504.             index=0;

  1505.         while(!avi->non_interleaved && index>0 && st2->index_entries[index-1].pos >= pos_min)

  1506.             index--;

  1507.         ast2->frame_offset = st2->index_entries[index].timestamp;

  1508.     }

  1509. 

  1510.     /* do the seek */

  1511.     if (avio_seek(s->pb, pos_min, SEEK_SET) < 0) {

  1512.         av_log(s, AV_LOG_ERROR, "Seek failed\n");

  1513.         return -1;

  1514.     }

  1515.     avi->stream_index= -1;

  1516.     avi->dts_max= INT_MIN;

  1517.     return 0;

  1518. }

  1519. 

  1520. static int avi_read_close(AVFormatContext *s)

  1521. {

  1522.     int i;

  1523.     AVIContext *avi = s->priv_data;

  1524. 

  1525.     for(i=0;i<s->nb_streams;i++) {

  1526.         AVStream *st = s->streams[i];

  1527.         AVIStream *ast = st->priv_data;

  1528.         if (ast) {

  1529.             if (ast->sub_ctx) {

  1530.                 av_freep(&ast->sub_ctx->pb);

  1531.                 avformat_close_input(&ast->sub_ctx);

  1532.             }

  1533.             av_free(ast->sub_buffer);

  1534.             av_free_packet(&ast->sub_pkt);

  1535.         }

  1536.     }

  1537. 

  1538.     av_free(avi->dv_demux);

  1539. 

  1540.     return 0;

  1541. }

  1542. 

  1543. static int avi_probe(AVProbeData *p)

  1544. {

  1545.     int i;

  1546. 

  1547.     /* check file header */

  1548.     for(i=0; avi_headers[i][0]; i++)

  1549.         if(!memcmp(p->buf  , avi_headers[i]  , 4) &&

  1550.            !memcmp(p->buf+8, avi_headers[i]+4, 4))

  1551.             return AVPROBE_SCORE_MAX;

  1552. 

  1553.     return 0;

  1554. }

  1555. 

  1556. AVInputFormat ff_avi_demuxer = {

  1557.     .name           = "avi",

  1558.     .long_name      = NULL_IF_CONFIG_SMALL("AVI format"),

  1559.     .priv_data_size = sizeof(AVIContext),

  1560.     .read_probe     = avi_probe,

  1561.     .read_header    = avi_read_header,

  1562.     .read_packet    = avi_read_packet,

  1563.     .read_close     = avi_read_close,

  1564.     .read_seek      = avi_read_seek,

  1565.     .priv_class = &demuxer_class,

  1566. };