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FFmpeg/libavformat/mpeg.c

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  1. /*

  2.  * MPEG-1/2 demuxer

  3.  * Copyright (c) 2000, 2001, 2002 Fabrice Bellard

  4.  *

  5.  * This file is part of Libav.

  6.  *

  7.  * Libav 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.  * Libav 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 Libav; if not, write to the Free Software

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

  20.  */

  21. 

  22. #include "avformat.h"

  23. #include "internal.h"

  24. #include "mpeg.h"

  25. 

  26. /*********************************************/

  27. /* demux code */

  28. 

  29. #define MAX_SYNC_SIZE 100000

  30. 

  31. static int check_pes(uint8_t *p, uint8_t *end)

  32. {

  33.     int pes1;

  34.     int pes2 = (p[3] & 0xC0) == 0x80 &&

  35.                (p[4] & 0xC0) != 0x40 &&

  36.                ((p[4] & 0xC0) == 0x00 ||

  37.                 (p[4] & 0xC0) >> 2 == (p[6] & 0xF0));

  38. 

  39.     for (p += 3; p < end && *p == 0xFF; p++) ;

  40.     if ((*p & 0xC0) == 0x40)

  41.         p += 2;

  42. 

  43.     if ((*p & 0xF0) == 0x20)

  44.         pes1 = p[0] & p[2] & p[4] & 1;

  45.     else if ((*p & 0xF0) == 0x30)

  46.         pes1 = p[0] & p[2] & p[4] & p[5] & p[7] & p[9] & 1;

  47.     else

  48.         pes1 = *p == 0x0F;

  49. 

  50.     return pes1 || pes2;

  51. }

  52. 

  53. static int check_pack_header(const uint8_t *buf)

  54. {

  55.     return (buf[1] & 0xC0) == 0x40 || (buf[1] & 0xF0) == 0x20;

  56. }

  57. 

  58. static int mpegps_probe(AVProbeData *p)

  59. {

  60.     uint32_t code = -1;

  61.     int i;

  62.     int sys = 0, pspack = 0, priv1 = 0, vid = 0;

  63.     int audio = 0, invalid = 0, score = 0;

  64. 

  65.     for (i = 0; i < p->buf_size; i++) {

  66.         code = (code << 8) + p->buf[i];

  67.         if ((code & 0xffffff00) == 0x100) {

  68.             int len  = p->buf[i + 1] << 8 | p->buf[i + 2];

  69.             int pes  = check_pes(p->buf + i, p->buf + p->buf_size);

  70.             int pack = check_pack_header(p->buf + i);

  71. 

  72.             if (code == SYSTEM_HEADER_START_CODE)

  73.                 sys++;

  74.             else if (code == PACK_START_CODE && pack)

  75.                 pspack++;

  76.             else if ((code & 0xf0) == VIDEO_ID && pes)

  77.                 vid++;

  78.             // skip pes payload to avoid start code emulation for private

  79.             // and audio streams

  80.             else if ((code & 0xe0) == AUDIO_ID && pes) {

  81.                 audio++;

  82.                 i += len;

  83.             } else if (code == PRIVATE_STREAM_1 && pes) {

  84.                 priv1++;

  85.                 i += len;

  86.             } else if ((code & 0xf0) == VIDEO_ID && !pes)

  87.                 invalid++;

  88.             else if ((code & 0xe0) == AUDIO_ID && !pes)

  89.                 invalid++;

  90.             else if (code == PRIVATE_STREAM_1 && !pes)

  91.                 invalid++;

  92.         }

  93.     }

  94. 

  95.     if (vid + audio > invalid)   /* invalid VDR files nd short PES streams */

  96.         score = AVPROBE_SCORE_EXTENSION / 2;

  97. 

  98.     if (sys > invalid && sys * 9 <= pspack * 10)

  99.         return pspack > 2 ? AVPROBE_SCORE_EXTENSION + 2

  100.                           : AVPROBE_SCORE_EXTENSION / 2; // 1 more than .mpg

  101.     if (pspack > invalid && (priv1 + vid + audio) * 10 >= pspack * 9)

  102.         return pspack > 2 ? AVPROBE_SCORE_EXTENSION + 2

  103.                           : AVPROBE_SCORE_EXTENSION / 2; // 1 more than .mpg

  104.     if ((!!vid ^ !!audio) && (audio > 4 || vid > 1) && !sys &&

  105.         !pspack && p->buf_size > 2048 && vid + audio > invalid) /* PES stream */

  106.         return (audio > 12 || vid > 3) ? AVPROBE_SCORE_EXTENSION + 2

  107.                                        : AVPROBE_SCORE_EXTENSION / 2;

  108. 

  109.     // 02-Penguin.flac has sys:0 priv1:0 pspack:0 vid:0 audio:1

  110.     // mp3_misidentified_2.mp3 has sys:0 priv1:0 pspack:0 vid:0 audio:6

  111.     return score;

  112. }

  113. 

  114. typedef struct MpegDemuxContext {

  115.     int32_t header_state;

  116.     unsigned char psm_es_type[256];

  117.     int sofdec;

  118. } MpegDemuxContext;

  119. 

  120. static int mpegps_read_header(AVFormatContext *s)

  121. {

  122.     MpegDemuxContext *m = s->priv_data;

  123.     const char *sofdec  = "Sofdec";

  124.     int v, i = 0;

  125. 

  126.     m->header_state = 0xff;

  127.     s->ctx_flags   |= AVFMTCTX_NOHEADER;

  128. 

  129.     m->sofdec = -1;

  130.     do {

  131.         v = avio_r8(s->pb);

  132.         m->header_state = m->header_state << 8 | v;

  133.         m->sofdec++;

  134.     } while (v == sofdec[i] && i++ < 6);

  135. 

  136.     m->sofdec = (m->sofdec == 6) ? 1 : 0;

  137. 

  138.     /* no need to do more */

  139.     return 0;

  140. }

  141. 

  142. static int64_t get_pts(AVIOContext *pb, int c)

  143. {

  144.     uint8_t buf[5];

  145. 

  146.     buf[0] = c < 0 ? avio_r8(pb) : c;

  147.     avio_read(pb, buf + 1, 4);

  148. 

  149.     return ff_parse_pes_pts(buf);

  150. }

  151. 

  152. static int find_next_start_code(AVIOContext *pb, int *size_ptr,

  153.                                 int32_t *header_state)

  154. {

  155.     unsigned int state, v;

  156.     int val, n;

  157. 

  158.     state = *header_state;

  159.     n     = *size_ptr;

  160.     while (n > 0) {

  161.         if (pb->eof_reached)

  162.             break;

  163.         v = avio_r8(pb);

  164.         n--;

  165.         if (state == 0x000001) {

  166.             state = ((state << 8) | v) & 0xffffff;

  167.             val   = state;

  168.             goto found;

  169.         }

  170.         state = ((state << 8) | v) & 0xffffff;

  171.     }

  172.     val = -1;

  173. 

  174. found:

  175.     *header_state = state;

  176.     *size_ptr     = n;

  177.     return val;

  178. }

  179. 

  180. /**

  181.  * Extract stream types from a program stream map

  182.  * According to ISO/IEC 13818-1 ('MPEG-2 Systems') table 2-35

  183.  *

  184.  * @return number of bytes occupied by PSM in the bitstream

  185.  */

  186. static long mpegps_psm_parse(MpegDemuxContext *m, AVIOContext *pb)

  187. {

  188.     int psm_length, ps_info_length, es_map_length;

  189. 

  190.     psm_length = avio_rb16(pb);

  191.     avio_r8(pb);

  192.     avio_r8(pb);

  193.     ps_info_length = avio_rb16(pb);

  194. 

  195.     /* skip program_stream_info */

  196.     avio_skip(pb, ps_info_length);

  197.     es_map_length = avio_rb16(pb);

  198. 

  199.     /* at least one es available? */

  200.     while (es_map_length >= 4) {

  201.         unsigned char type      = avio_r8(pb);

  202.         unsigned char es_id     = avio_r8(pb);

  203.         uint16_t es_info_length = avio_rb16(pb);

  204. 

  205.         /* remember mapping from stream id to stream type */

  206.         m->psm_es_type[es_id] = type;

  207.         /* skip program_stream_info */

  208.         avio_skip(pb, es_info_length);

  209.         es_map_length -= 4 + es_info_length;

  210.     }

  211.     avio_rb32(pb); /* crc32 */

  212.     return 2 + psm_length;

  213. }

  214. 

  215. /* read the next PES header. Return its position in ppos

  216.  * (if not NULL), and its start code, pts and dts.

  217.  */

  218. static int mpegps_read_pes_header(AVFormatContext *s,

  219.                                   int64_t *ppos, int *pstart_code,

  220.                                   int64_t *ppts, int64_t *pdts)

  221. {

  222.     MpegDemuxContext *m = s->priv_data;

  223.     int len, size, startcode, c, flags, header_len;

  224.     int pes_ext, ext2_len, id_ext, skip;

  225.     int64_t pts, dts;

  226.     int64_t last_sync = avio_tell(s->pb);

  227. 

  228. error_redo:

  229.     avio_seek(s->pb, last_sync, SEEK_SET);

  230. redo:

  231.     /* next start code (should be immediately after) */

  232.     m->header_state = 0xff;

  233.     size      = MAX_SYNC_SIZE;

  234.     startcode = find_next_start_code(s->pb, &size, &m->header_state);

  235.     last_sync = avio_tell(s->pb);

  236.     if (startcode < 0) {

  237.         if (s->pb->eof_reached)

  238.             return AVERROR_EOF;

  239.         // FIXME we should remember header_state

  240.         return AVERROR(EAGAIN);

  241.     }

  242. 

  243.     if (startcode == PACK_START_CODE)

  244.         goto redo;

  245.     if (startcode == SYSTEM_HEADER_START_CODE)

  246.         goto redo;

  247.     if (startcode == PADDING_STREAM) {

  248.         avio_skip(s->pb, avio_rb16(s->pb));

  249.         goto redo;

  250.     }

  251.     if (startcode == PRIVATE_STREAM_2) {

  252.         len = avio_rb16(s->pb);

  253.         if (!m->sofdec) {

  254.             while (len-- >= 6) {

  255.                 if (avio_r8(s->pb) == 'S') {

  256.                     uint8_t buf[5];

  257.                     avio_read(s->pb, buf, sizeof(buf));

  258.                     m->sofdec = !memcmp(buf, "ofdec", 5);

  259.                     len -= sizeof(buf);

  260.                     break;

  261.                 }

  262.             }

  263.             m->sofdec -= !m->sofdec;

  264.         }

  265.         avio_skip(s->pb, len);

  266.         goto redo;

  267.     }

  268.     if (startcode == PROGRAM_STREAM_MAP) {

  269.         mpegps_psm_parse(m, s->pb);

  270.         goto redo;

  271.     }

  272. 

  273.     /* find matching stream */

  274.     if (!((startcode >= 0x1c0 && startcode <= 0x1df) ||

  275.           (startcode >= 0x1e0 && startcode <= 0x1ef) ||

  276.           (startcode == 0x1bd) || (startcode == 0x1fd)))

  277.         goto redo;

  278.     if (ppos) {

  279.         *ppos = avio_tell(s->pb) - 4;

  280.     }

  281.     len = avio_rb16(s->pb);

  282.     pts =

  283.     dts = AV_NOPTS_VALUE;

  284.     /* stuffing */

  285.     for (;;) {

  286.         if (len < 1)

  287.             goto error_redo;

  288.         c = avio_r8(s->pb);

  289.         len--;

  290.         /* XXX: for MPEG-1, should test only bit 7 */

  291.         if (c != 0xff)

  292.             break;

  293.     }

  294.     if ((c & 0xc0) == 0x40) {

  295.         /* buffer scale & size */

  296.         avio_r8(s->pb);

  297.         c    = avio_r8(s->pb);

  298.         len -= 2;

  299.     }

  300.     if ((c & 0xe0) == 0x20) {

  301.         dts  =

  302.         pts  = get_pts(s->pb, c);

  303.         len -= 4;

  304.         if (c & 0x10) {

  305.             dts  = get_pts(s->pb, -1);

  306.             len -= 5;

  307.         }

  308.     } else if ((c & 0xc0) == 0x80) {

  309.         /* mpeg 2 PES */

  310.         flags      = avio_r8(s->pb);

  311.         header_len = avio_r8(s->pb);

  312.         len       -= 2;

  313.         if (header_len > len)

  314.             goto error_redo;

  315.         len -= header_len;

  316.         if (flags & 0x80) {

  317.             dts         = pts = get_pts(s->pb, -1);

  318.             header_len -= 5;

  319.             if (flags & 0x40) {

  320.                 dts         = get_pts(s->pb, -1);

  321.                 header_len -= 5;

  322.             }

  323.         }

  324.         if (flags & 0x3f && header_len == 0) {

  325.             flags &= 0xC0;

  326.             av_log(s, AV_LOG_WARNING, "Further flags set but no bytes left\n");

  327.         }

  328.         if (flags & 0x01) { /* PES extension */

  329.             pes_ext = avio_r8(s->pb);

  330.             header_len--;

  331.             /* Skip PES private data, program packet sequence counter

  332.              * and P-STD buffer */

  333.             skip  = (pes_ext >> 4) & 0xb;

  334.             skip += skip & 0x9;

  335.             if (pes_ext & 0x40 || skip > header_len) {

  336.                 av_log(s, AV_LOG_WARNING, "pes_ext %X is invalid\n", pes_ext);

  337.                 pes_ext = skip = 0;

  338.             }

  339.             avio_skip(s->pb, skip);

  340.             header_len -= skip;

  341. 

  342.             if (pes_ext & 0x01) { /* PES extension 2 */

  343.                 ext2_len = avio_r8(s->pb);

  344.                 header_len--;

  345.                 if ((ext2_len & 0x7f) > 0) {

  346.                     id_ext = avio_r8(s->pb);

  347.                     if ((id_ext & 0x80) == 0)

  348.                         startcode = ((startcode & 0xff) << 8) | id_ext;

  349.                     header_len--;

  350.                 }

  351.             }

  352.         }

  353.         if (header_len < 0)

  354.             goto error_redo;

  355.         avio_skip(s->pb, header_len);

  356.     } else if (c != 0xf)

  357.         goto redo;

  358. 

  359.     if (startcode == PRIVATE_STREAM_1 && !m->psm_es_type[startcode & 0xff]) {

  360.         startcode = avio_r8(s->pb);

  361.         len--;

  362.         if (startcode >= 0x80 && startcode <= 0xcf) {

  363.             /* audio: skip header */

  364.             avio_r8(s->pb);

  365.             avio_r8(s->pb);

  366.             avio_r8(s->pb);

  367.             len -= 3;

  368.             if (startcode >= 0xb0 && startcode <= 0xbf) {

  369.                 /* MLP/TrueHD audio has a 4-byte header */

  370.                 avio_r8(s->pb);

  371.                 len--;

  372.             }

  373.         }

  374.     }

  375.     if (len < 0)

  376.         goto error_redo;

  377.     if (dts != AV_NOPTS_VALUE && ppos) {

  378.         int i;

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

  380.             if (startcode == s->streams[i]->id &&

  381.                 (s->pb->seekable & AVIO_SEEKABLE_NORMAL) /* index useless on streams anyway */) {

  382.                 ff_reduce_index(s, i);

  383.                 av_add_index_entry(s->streams[i], *ppos, dts, 0, 0,

  384.                                    AVINDEX_KEYFRAME /* FIXME keyframe? */);

  385.             }

  386.         }

  387.     }

  388. 

  389.     *pstart_code = startcode;

  390.     *ppts        = pts;

  391.     *pdts        = dts;

  392.     return len;

  393. }

  394. 

  395. static int mpegps_read_packet(AVFormatContext *s,

  396.                               AVPacket *pkt)

  397. {

  398.     MpegDemuxContext *m = s->priv_data;

  399.     AVStream *st;

  400.     int len, startcode, i, es_type, ret;

  401.     enum AVCodecID codec_id = AV_CODEC_ID_NONE;

  402.     enum AVMediaType type;

  403.     int64_t pts, dts, dummy_pos; // dummy_pos is needed for the index building to work

  404.     uint8_t av_uninit(dvdaudio_substream_type);

  405. 

  406. redo:

  407.     len = mpegps_read_pes_header(s, &dummy_pos, &startcode, &pts, &dts);

  408.     if (len < 0)

  409.         return len;

  410. 

  411.     if (startcode == 0x1bd) {

  412.         dvdaudio_substream_type = avio_r8(s->pb);

  413.         avio_skip(s->pb, 3);

  414.         len -= 4;

  415.     }

  416. 

  417.     /* now find stream */

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

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

  420.         if (st->id == startcode)

  421.             goto found;

  422.     }

  423. 

  424.     es_type = m->psm_es_type[startcode & 0xff];

  425.     if (es_type > 0 && es_type != STREAM_TYPE_PRIVATE_DATA) {

  426.         if (es_type == STREAM_TYPE_VIDEO_MPEG1) {

  427.             codec_id = AV_CODEC_ID_MPEG2VIDEO;

  428.             type     = AVMEDIA_TYPE_VIDEO;

  429.         } else if (es_type == STREAM_TYPE_VIDEO_MPEG2) {

  430.             codec_id = AV_CODEC_ID_MPEG2VIDEO;

  431.             type     = AVMEDIA_TYPE_VIDEO;

  432.         } else if (es_type == STREAM_TYPE_AUDIO_MPEG1 ||

  433.                    es_type == STREAM_TYPE_AUDIO_MPEG2) {

  434.             codec_id = AV_CODEC_ID_MP3;

  435.             type     = AVMEDIA_TYPE_AUDIO;

  436.         } else if (es_type == STREAM_TYPE_AUDIO_AAC) {

  437.             codec_id = AV_CODEC_ID_AAC;

  438.             type     = AVMEDIA_TYPE_AUDIO;

  439.         } else if (es_type == STREAM_TYPE_VIDEO_MPEG4) {

  440.             codec_id = AV_CODEC_ID_MPEG4;

  441.             type     = AVMEDIA_TYPE_VIDEO;

  442.         } else if (es_type == STREAM_TYPE_VIDEO_H264) {

  443.             codec_id = AV_CODEC_ID_H264;

  444.             type     = AVMEDIA_TYPE_VIDEO;

  445.         } else if (es_type == STREAM_TYPE_AUDIO_AC3) {

  446.             codec_id = AV_CODEC_ID_AC3;

  447.             type     = AVMEDIA_TYPE_AUDIO;

  448.         } else {

  449.             goto skip;

  450.         }

  451.     } else if (startcode >= 0x1e0 && startcode <= 0x1ef) {

  452.         static const unsigned char avs_seqh[4] = { 0, 0, 1, 0xb0 };

  453.         unsigned char buf[8];

  454. 

  455.         avio_read(s->pb, buf, 8);

  456.         avio_seek(s->pb, -8, SEEK_CUR);

  457.         if (!memcmp(buf, avs_seqh, 4) && (buf[6] != 0 || buf[7] != 1))

  458.             codec_id = AV_CODEC_ID_CAVS;

  459.         else

  460.             codec_id = AV_CODEC_ID_PROBE;

  461.         type = AVMEDIA_TYPE_VIDEO;

  462.     } else if (startcode >= 0x1c0 && startcode <= 0x1df) {

  463.         type     = AVMEDIA_TYPE_AUDIO;

  464.         codec_id = m->sofdec > 0 ? AV_CODEC_ID_ADPCM_ADX : AV_CODEC_ID_MP2;

  465.     } else if (startcode >= 0x80 && startcode <= 0x87) {

  466.         type     = AVMEDIA_TYPE_AUDIO;

  467.         codec_id = AV_CODEC_ID_AC3;

  468.     } else if ((startcode >= 0x88 && startcode <= 0x8f) ||

  469.                (startcode >= 0x98 && startcode <= 0x9f)) {

  470.         /* 0x90 - 0x97 is reserved for SDDS in DVD specs */

  471.         type     = AVMEDIA_TYPE_AUDIO;

  472.         codec_id = AV_CODEC_ID_DTS;

  473.     } else if (startcode >= 0xa0 && startcode <= 0xaf) {

  474.         type     = AVMEDIA_TYPE_AUDIO;

  475.         codec_id = AV_CODEC_ID_PCM_DVD;

  476.     } else if (startcode >= 0xb0 && startcode <= 0xbf) {

  477.         type     = AVMEDIA_TYPE_AUDIO;

  478.         codec_id = AV_CODEC_ID_TRUEHD;

  479.     } else if (startcode >= 0xc0 && startcode <= 0xcf) {

  480.         /* Used for both AC-3 and E-AC-3 in EVOB files */

  481.         type     = AVMEDIA_TYPE_AUDIO;

  482.         codec_id = AV_CODEC_ID_AC3;

  483.     } else if (startcode >= 0x20 && startcode <= 0x3f) {

  484.         type     = AVMEDIA_TYPE_SUBTITLE;

  485.         codec_id = AV_CODEC_ID_DVD_SUBTITLE;

  486.     } else if (startcode >= 0xfd55 && startcode <= 0xfd5f) {

  487.         type     = AVMEDIA_TYPE_VIDEO;

  488.         codec_id = AV_CODEC_ID_VC1;

  489.     } else if (startcode == 0x1bd) {

  490.         // check dvd audio substream type

  491.         type = AVMEDIA_TYPE_AUDIO;

  492.         switch (dvdaudio_substream_type & 0xe0) {

  493.         case 0xa0:

  494.             codec_id = AV_CODEC_ID_PCM_DVD;

  495.             break;

  496.         case 0x80:

  497.             if ((dvdaudio_substream_type & 0xf8) == 0x88)

  498.                 codec_id = AV_CODEC_ID_DTS;

  499.             else

  500.                 codec_id = AV_CODEC_ID_AC3;

  501.             break;

  502.         default:

  503.             av_log(s, AV_LOG_ERROR, "Unknown 0x1bd sub-stream\n");

  504.             goto skip;

  505.         }

  506.     } else {

  507. skip:

  508.         /* skip packet */

  509.         avio_skip(s->pb, len);

  510.         goto redo;

  511.     }

  512.     /* no stream found: add a new stream */

  513.     st = avformat_new_stream(s, NULL);

  514.     if (!st)

  515.         goto skip;

  516.     st->id                = startcode;

  517.     st->codecpar->codec_type = type;

  518.     st->codecpar->codec_id   = codec_id;

  519.     st->need_parsing      = AVSTREAM_PARSE_FULL;

  520. 

  521. found:

  522.     if (st->discard >= AVDISCARD_ALL)

  523.         goto skip;

  524.     ret = av_get_packet(s->pb, pkt, len);

  525. 

  526.     pkt->pts          = pts;

  527.     pkt->dts          = dts;

  528.     pkt->pos          = dummy_pos;

  529.     pkt->stream_index = st->index;

  530.     av_log(s, AV_LOG_TRACE, "%d: pts=%0.3f dts=%0.3f size=%d\n",

  531.             pkt->stream_index, pkt->pts / 90000.0, pkt->dts / 90000.0,

  532.             pkt->size);

  533. 

  534.     return (ret < 0) ? ret : 0;

  535. }

  536. 

  537. static int64_t mpegps_read_dts(AVFormatContext *s, int stream_index,

  538.                                int64_t *ppos, int64_t pos_limit)

  539. {

  540.     int len, startcode;

  541.     int64_t pos, pts, dts;

  542. 

  543.     pos = *ppos;

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

  545.         return AV_NOPTS_VALUE;

  546. 

  547.     for (;;) {

  548.         len = mpegps_read_pes_header(s, &pos, &startcode, &pts, &dts);

  549.         if (len < 0) {

  550.             av_log(s, AV_LOG_TRACE, "none (ret=%d)\n", len);

  551.             return AV_NOPTS_VALUE;

  552.         }

  553.         if (startcode == s->streams[stream_index]->id &&

  554.             dts != AV_NOPTS_VALUE) {

  555.             break;

  556.         }

  557.         avio_skip(s->pb, len);

  558.     }

  559.     av_log(s, AV_LOG_TRACE, "pos=0x%"PRIx64" dts=0x%"PRIx64" %0.3f\n",

  560.             pos, dts, dts / 90000.0);

  561.     *ppos = pos;

  562.     return dts;

  563. }

  564. 

  565. AVInputFormat ff_mpegps_demuxer = {

  566.     .name           = "mpeg",

  567.     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-PS (MPEG-2 Program Stream)"),

  568.     .priv_data_size = sizeof(MpegDemuxContext),

  569.     .read_probe     = mpegps_probe,

  570.     .read_header    = mpegps_read_header,

  571.     .read_packet    = mpegps_read_packet,

  572.     .read_timestamp = mpegps_read_dts,

  573.     .flags          = AVFMT_SHOW_IDS | AVFMT_TS_DISCONT,

  574. };