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  1. /*
  2.  * Windows Television (WTV) demuxer
  3.  * Copyright (c) 2010-2011 Peter Ross <pross@xvid.org>
  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. /**
  23.  * @file
  24.  * Windows Television (WTV) demuxer
  25.  * @author Peter Ross <pross@xvid.org>
  26.  */
  27.  
  28. #include "libavutil/channel_layout.h"
  29. #include "libavutil/intreadwrite.h"
  30. #include "libavutil/intfloat.h"
  31. #include "avformat.h"
  32. #include "internal.h"
  33. #include "wtv.h"
  34. #include "mpegts.h"
  35.  
  36. /* Macros for formating GUIDs */
  37. #define PRI_PRETTY_GUID \
  38.     "%08x-%04x-%04x-%02x%02x%02x%02x%02x%02x%02x%02x"
  39. #define ARG_PRETTY_GUID(g) \
  40.     AV_RL32(g),AV_RL16(g+4),AV_RL16(g+6),g[8],g[9],g[10],g[11],g[12],g[13],g[14],g[15]
  41. #define LEN_PRETTY_GUID 34
  42.  
  43. /*
  44.  *
  45.  * File system routines
  46.  *
  47.  */
  48.  
  49. typedef struct {
  50.     AVIOContext *pb_filesystem;  /**< file system (AVFormatContext->pb) */
  51.  
  52.     int sector_bits;     /**< sector shift bits; used to convert sector number into pb_filesystem offset */
  53.     uint32_t *sectors;   /**< file allocation table */
  54.     int nb_sectors;      /**< number of sectors */
  55.  
  56.     int error;
  57.     int64_t position;
  58.     int64_t length;
  59. } WtvFile;
  60.  
  61. static int64_t seek_by_sector(AVIOContext *pb, int64_t sector, int64_t offset)
  62. {
  63.     return avio_seek(pb, (sector << WTV_SECTOR_BITS) + offset, SEEK_SET);
  64. }
  65.  
  66. /**
  67.  * @return bytes read, 0 on end of file, or <0 on error
  68.  */
  69. static int wtvfile_read_packet(void *opaque, uint8_t *buf, int buf_size)
  70. {
  71.     WtvFile *wf = opaque;
  72.     AVIOContext *pb = wf->pb_filesystem;
  73.     int nread = 0;
  74.  
  75.     if (wf->error || pb->error)
  76.         return -1;
  77.     if (wf->position >= wf->length || url_feof(pb))
  78.         return 0;
  79.  
  80.     buf_size = FFMIN(buf_size, wf->length - wf->position);
  81.     while(nread < buf_size) {
  82.         int n;
  83.         int remaining_in_sector = (1 << wf->sector_bits) - (wf->position & ((1 << wf->sector_bits) - 1));
  84.         int read_request        = FFMIN(buf_size - nread, remaining_in_sector);
  85.  
  86.         n = avio_read(pb, buf, read_request);
  87.         if (n <= 0)
  88.             break;
  89.         nread += n;
  90.         buf += n;
  91.         wf->position += n;
  92.         if (n == remaining_in_sector) {
  93.             int i = wf->position >> wf->sector_bits;
  94.             if (i >= wf->nb_sectors ||
  95.                 (wf->sectors[i] != wf->sectors[i - 1] + (1 << (wf->sector_bits - WTV_SECTOR_BITS)) &&
  96.                 seek_by_sector(pb, wf->sectors[i], 0) < 0)) {
  97.                 wf->error = 1;
  98.                 break;
  99.             }
  100.         }
  101.     }
  102.     return nread;
  103. }
  104.  
  105. /**
  106.  * @return position (or file length)
  107.  */
  108. static int64_t wtvfile_seek(void *opaque, int64_t offset, int whence)
  109. {
  110.     WtvFile *wf = opaque;
  111.     AVIOContext *pb = wf->pb_filesystem;
  112.  
  113.     if (whence == AVSEEK_SIZE)
  114.         return wf->length;
  115.     else if (whence == SEEK_CUR)
  116.         offset = wf->position + offset;
  117.     else if (whence == SEEK_END)
  118.         offset = wf->length;
  119.  
  120.     wf->error = offset < 0 || offset >= wf->length ||
  121.                 seek_by_sector(pb, wf->sectors[offset >> wf->sector_bits],
  122.                                offset & ((1 << wf->sector_bits) - 1)) < 0;
  123.     wf->position = offset;
  124.     return offset;
  125. }
  126.  
  127. /**
  128.  * read non-zero integers (le32) from input stream
  129.  * @param pb
  130.  * @param[out] data destination
  131.  * @param     count maximum number of integers to read
  132.  * @return    total number of integers read
  133.  */
  134. static int read_ints(AVIOContext *pb, uint32_t *data, int count)
  135. {
  136.     int i, total = 0;
  137.     for (i = 0; i < count; i++) {
  138.         if ((data[total] = avio_rl32(pb)))
  139.            total++;
  140.     }
  141.     return total;
  142. }
  143.  
  144. /**
  145.  * Open file
  146.  * @param first_sector  First sector
  147.  * @param length        Length of file (bytes)
  148.  * @param depth         File allocation table depth
  149.  * @return NULL on error
  150.  */
  151. static AVIOContext * wtvfile_open_sector(int first_sector, uint64_t length, int depth, AVFormatContext *s)
  152. {
  153.     AVIOContext *pb;
  154.     WtvFile *wf;
  155.     uint8_t *buffer;
  156.  
  157.     if (seek_by_sector(s->pb, first_sector, 0) < 0)
  158.         return NULL;
  159.  
  160.     wf = av_mallocz(sizeof(WtvFile));
  161.     if (!wf)
  162.         return NULL;
  163.  
  164.     if (depth == 0) {
  165.         wf->sectors = av_malloc(sizeof(uint32_t));
  166.         if (!wf->sectors) {
  167.             av_free(wf);
  168.             return NULL;
  169.         }
  170.         wf->sectors[0]  = first_sector;
  171.         wf->nb_sectors  = 1;
  172.     } else if (depth == 1) {
  173.         wf->sectors = av_malloc(WTV_SECTOR_SIZE);
  174.         if (!wf->sectors) {
  175.             av_free(wf);
  176.             return NULL;
  177.         }
  178.         wf->nb_sectors  = read_ints(s->pb, wf->sectors, WTV_SECTOR_SIZE / 4);
  179.     } else if (depth == 2) {
  180.         uint32_t sectors1[WTV_SECTOR_SIZE / 4];
  181.         int nb_sectors1 = read_ints(s->pb, sectors1, WTV_SECTOR_SIZE / 4);
  182.         int i;
  183.  
  184.         wf->sectors = av_malloc_array(nb_sectors1, 1 << WTV_SECTOR_BITS);
  185.         if (!wf->sectors) {
  186.             av_free(wf);
  187.             return NULL;
  188.         }
  189.         wf->nb_sectors = 0;
  190.         for (i = 0; i < nb_sectors1; i++) {
  191.             if (seek_by_sector(s->pb, sectors1[i], 0) < 0)
  192.                 break;
  193.             wf->nb_sectors += read_ints(s->pb, wf->sectors + i * WTV_SECTOR_SIZE / 4, WTV_SECTOR_SIZE / 4);
  194.         }
  195.     } else {
  196.         av_log(s, AV_LOG_ERROR, "unsupported file allocation table depth (0x%x)\n", depth);
  197.         av_free(wf);
  198.         return NULL;
  199.     }
  200.     wf->sector_bits = length & (1ULL<<63) ? WTV_SECTOR_BITS : WTV_BIGSECTOR_BITS;
  201.  
  202.     if (!wf->nb_sectors) {
  203.         av_free(wf->sectors);
  204.         av_free(wf);
  205.         return NULL;
  206.     }
  207.  
  208.     if ((int64_t)wf->sectors[wf->nb_sectors - 1] << WTV_SECTOR_BITS > avio_tell(s->pb))
  209.         av_log(s, AV_LOG_WARNING, "truncated file\n");
  210.  
  211.     /* check length */
  212.     length &= 0xFFFFFFFFFFFF;
  213.     if (length > ((int64_t)wf->nb_sectors << wf->sector_bits)) {
  214.         av_log(s, AV_LOG_WARNING, "reported file length (0x%"PRIx64") exceeds number of available sectors (0x%"PRIx64")\n", length, (int64_t)wf->nb_sectors << wf->sector_bits);
  215.         length = (int64_t)wf->nb_sectors <<  wf->sector_bits;
  216.     }
  217.     wf->length = length;
  218.  
  219.     /* seek to initial sector */
  220.     wf->position = 0;
  221.     if (seek_by_sector(s->pb, wf->sectors[0], 0) < 0) {
  222.         av_free(wf->sectors);
  223.         av_free(wf);
  224.         return NULL;
  225.     }
  226.  
  227.     wf->pb_filesystem = s->pb;
  228.     buffer = av_malloc(1 << wf->sector_bits);
  229.     if (!buffer) {
  230.         av_free(wf->sectors);
  231.         av_free(wf);
  232.         return NULL;
  233.     }
  234.  
  235.     pb = avio_alloc_context(buffer, 1 << wf->sector_bits, 0, wf,
  236.                            wtvfile_read_packet, NULL, wtvfile_seek);
  237.     if (!pb) {
  238.         av_free(buffer);
  239.         av_free(wf->sectors);
  240.         av_free(wf);
  241.     }
  242.     return pb;
  243. }
  244.  
  245. /**
  246.  * Open file using filename
  247.  * @param[in]  buf       directory buffer
  248.  * @param      buf_size  directory buffer size
  249.  * @param[in]  filename
  250.  * @param      filename_size size of filename
  251.  * @return NULL on error
  252.  */
  253. static AVIOContext * wtvfile_open2(AVFormatContext *s, const uint8_t *buf, int buf_size, const uint8_t *filename, int filename_size)
  254. {
  255.     const uint8_t *buf_end = buf + buf_size;
  256.  
  257.     while(buf + 48 <= buf_end) {
  258.         int dir_length, name_size, first_sector, depth;
  259.         uint64_t file_length;
  260.         const uint8_t *name;
  261.         if (ff_guidcmp(buf, ff_dir_entry_guid)) {
  262.             av_log(s, AV_LOG_ERROR, "unknown guid "FF_PRI_GUID", expected dir_entry_guid; "
  263.                    "remaining directory entries ignored\n", FF_ARG_GUID(buf));
  264.             break;
  265.         }
  266.         dir_length  = AV_RL16(buf + 16);
  267.         file_length = AV_RL64(buf + 24);
  268.         name_size   = 2 * AV_RL32(buf + 32);
  269.         if (name_size < 0) {
  270.             av_log(s, AV_LOG_ERROR,
  271.                    "bad filename length, remaining directory entries ignored\n");
  272.             break;
  273.         }
  274.         if (48 + (int64_t)name_size > buf_end - buf) {
  275.             av_log(s, AV_LOG_ERROR, "filename exceeds buffer size; remaining directory entries ignored\n");
  276.             break;
  277.         }
  278.         first_sector = AV_RL32(buf + 40 + name_size);
  279.         depth        = AV_RL32(buf + 44 + name_size);
  280.  
  281.         /* compare file name; test optional null terminator */
  282.         name = buf + 40;
  283.         if (name_size >= filename_size &&
  284.             !memcmp(name, filename, filename_size) &&
  285.             (name_size < filename_size + 2 || !AV_RN16(name + filename_size)))
  286.             return wtvfile_open_sector(first_sector, file_length, depth, s);
  287.  
  288.         buf += dir_length;
  289.     }
  290.     return 0;
  291. }
  292.  
  293. #define wtvfile_open(s, buf, buf_size, filename) \
  294.     wtvfile_open2(s, buf, buf_size, filename, sizeof(filename))
  295.  
  296. /**
  297.  * Close file opened with wtvfile_open_sector(), or wtv_open()
  298.  */
  299. static void wtvfile_close(AVIOContext *pb)
  300. {
  301.     WtvFile *wf = pb->opaque;
  302.     av_free(wf->sectors);
  303.     av_freep(&pb->opaque);
  304.     av_freep(&pb->buffer);
  305.     av_free(pb);
  306. }
  307.  
  308. /*
  309.  *
  310.  * Main demuxer
  311.  *
  312.  */
  313.  
  314. typedef struct {
  315.     int seen_data;
  316. } WtvStream;
  317.  
  318. typedef struct {
  319.     AVIOContext *pb;       /**< timeline file */
  320.     int64_t epoch;
  321.     int64_t pts;             /**< pts for next data chunk */
  322.     int64_t last_valid_pts;  /**< latest valid pts, used for interative seeking */
  323.  
  324.     /* maintain private seek index, as the AVIndexEntry->pos is relative to the
  325.        start of the 'timeline' file, not the file system (AVFormatContext->pb) */
  326.     AVIndexEntry *index_entries;
  327.     int nb_index_entries;
  328.     unsigned int index_entries_allocated_size;
  329. } WtvContext;
  330.  
  331. /* WTV GUIDs */
  332. static const ff_asf_guid EVENTID_SubtitleSpanningEvent =
  333.     {0x48,0xC0,0xCE,0x5D,0xB9,0xD0,0x63,0x41,0x87,0x2C,0x4F,0x32,0x22,0x3B,0xE8,0x8A};
  334. static const ff_asf_guid EVENTID_LanguageSpanningEvent =
  335.     {0x6D,0x66,0x92,0xE2,0x02,0x9C,0x8D,0x44,0xAA,0x8D,0x78,0x1A,0x93,0xFD,0xC3,0x95};
  336. static const ff_asf_guid EVENTID_AudioDescriptorSpanningEvent =
  337.     {0x1C,0xD4,0x7B,0x10,0xDA,0xA6,0x91,0x46,0x83,0x69,0x11,0xB2,0xCD,0xAA,0x28,0x8E};
  338. static const ff_asf_guid EVENTID_CtxADescriptorSpanningEvent =
  339.     {0xE6,0xA2,0xB4,0x3A,0x47,0x42,0x34,0x4B,0x89,0x6C,0x30,0xAF,0xA5,0xD2,0x1C,0x24};
  340. static const ff_asf_guid EVENTID_CSDescriptorSpanningEvent =
  341.     {0xD9,0x79,0xE7,0xEf,0xF0,0x97,0x86,0x47,0x80,0x0D,0x95,0xCF,0x50,0x5D,0xDC,0x66};
  342. static const ff_asf_guid EVENTID_DVBScramblingControlSpanningEvent =
  343.     {0xC4,0xE1,0xD4,0x4B,0xA1,0x90,0x09,0x41,0x82,0x36,0x27,0xF0,0x0E,0x7D,0xCC,0x5B};
  344. static const ff_asf_guid EVENTID_StreamIDSpanningEvent =
  345.     {0x68,0xAB,0xF1,0xCA,0x53,0xE1,0x41,0x4D,0xA6,0xB3,0xA7,0xC9,0x98,0xDB,0x75,0xEE};
  346. static const ff_asf_guid EVENTID_TeletextSpanningEvent =
  347.     {0x50,0xD9,0x99,0x95,0x33,0x5F,0x17,0x46,0xAF,0x7C,0x1E,0x54,0xB5,0x10,0xDA,0xA3};
  348. static const ff_asf_guid EVENTID_AudioTypeSpanningEvent =
  349.     {0xBE,0xBF,0x1C,0x50,0x49,0xB8,0xCE,0x42,0x9B,0xE9,0x3D,0xB8,0x69,0xFB,0x82,0xB3};
  350.  
  351. /* Windows media GUIDs */
  352.  
  353. /* Media types */
  354. static const ff_asf_guid mediasubtype_mpeg1payload =
  355.     {0x81,0xEB,0x36,0xE4,0x4F,0x52,0xCE,0x11,0x9F,0x53,0x00,0x20,0xAF,0x0B,0xA7,0x70};
  356. static const ff_asf_guid mediatype_mpeg2_sections =
  357.     {0x6C,0x17,0x5F,0x45,0x06,0x4B,0xCE,0x47,0x9A,0xEF,0x8C,0xAE,0xF7,0x3D,0xF7,0xB5};
  358. static const ff_asf_guid mediatype_mpeg2_pes =
  359.     {0x20,0x80,0x6D,0xE0,0x46,0xDB,0xCF,0x11,0xB4,0xD1,0x00,0x80,0x5F,0x6C,0xBB,0xEA};
  360. static const ff_asf_guid mediatype_mstvcaption =
  361.     {0x89,0x8A,0x8B,0xB8,0x49,0xB0,0x80,0x4C,0xAD,0xCF,0x58,0x98,0x98,0x5E,0x22,0xC1};
  362.  
  363. /* Media subtypes */
  364. static const ff_asf_guid mediasubtype_dvb_subtitle =
  365.     {0xC3,0xCB,0xFF,0x34,0xB3,0xD5,0x71,0x41,0x90,0x02,0xD4,0xC6,0x03,0x01,0x69,0x7F};
  366. static const ff_asf_guid mediasubtype_teletext =
  367.     {0xE3,0x76,0x2A,0xF7,0x0A,0xEB,0xD0,0x11,0xAC,0xE4,0x00,0x00,0xC0,0xCC,0x16,0xBA};
  368. static const ff_asf_guid mediasubtype_dtvccdata =
  369.     {0xAA,0xDD,0x2A,0xF5,0xF0,0x36,0xF5,0x43,0x95,0xEA,0x6D,0x86,0x64,0x84,0x26,0x2A};
  370. static const ff_asf_guid mediasubtype_mpeg2_sections =
  371.     {0x79,0x85,0x9F,0x4A,0xF8,0x6B,0x92,0x43,0x8A,0x6D,0xD2,0xDD,0x09,0xFA,0x78,0x61};
  372.  
  373. /* Formats */
  374. static const ff_asf_guid format_videoinfo2 =
  375.     {0xA0,0x76,0x2A,0xF7,0x0A,0xEB,0xD0,0x11,0xAC,0xE4,0x00,0x00,0xC0,0xCC,0x16,0xBA};
  376.  
  377. static int read_probe(AVProbeData *p)
  378. {
  379.     return ff_guidcmp(p->buf, ff_wtv_guid) ? 0 : AVPROBE_SCORE_MAX;
  380. }
  381.  
  382. /**
  383.  * Convert win32 FILETIME to ISO-8601 string
  384.  * @return <0 on error
  385.  */
  386. static int filetime_to_iso8601(char *buf, int buf_size, int64_t value)
  387. {
  388.     time_t t = (value / 10000000LL) - 11644473600LL;
  389.     struct tm *tm = gmtime(&t);
  390.     if (!tm)
  391.         return -1;
  392.     strftime(buf, buf_size, "%Y-%m-%d %H:%M:%S", gmtime(&t));
  393.     return 0;
  394. }
  395.  
  396. /**
  397.  * Convert crazy time (100ns since 1 Jan 0001) to ISO-8601 string
  398.  * @return <0 on error
  399.  */
  400. static int crazytime_to_iso8601(char *buf, int buf_size, int64_t value)
  401. {
  402.     time_t t = (value / 10000000LL) - 719162LL*86400LL;
  403.     struct tm *tm = gmtime(&t);
  404.     if (!tm)
  405.         return -1;
  406.     strftime(buf, buf_size, "%Y-%m-%d %H:%M:%S", gmtime(&t));
  407.     return 0;
  408. }
  409.  
  410. /**
  411.  * Convert OLE DATE to ISO-8601 string
  412.  * @return <0 on error
  413.  */
  414. static int oledate_to_iso8601(char *buf, int buf_size, int64_t value)
  415. {
  416.     time_t t = (av_int2double(value) - 25569.0) * 86400;
  417.     struct tm *result= gmtime(&t);
  418.     if (!result)
  419.         return -1;
  420.     strftime(buf, buf_size, "%Y-%m-%d %H:%M:%S", result);
  421.     return 0;
  422. }
  423.  
  424. static void get_attachment(AVFormatContext *s, AVIOContext *pb, int length)
  425. {
  426.     char mime[1024];
  427.     char description[1024];
  428.     unsigned int filesize;
  429.     AVStream *st;
  430.     int ret;
  431.     int64_t pos = avio_tell(pb);
  432.  
  433.     avio_get_str16le(pb, INT_MAX, mime, sizeof(mime));
  434.     if (strcmp(mime, "image/jpeg"))
  435.         goto done;
  436.  
  437.     avio_r8(pb);
  438.     avio_get_str16le(pb, INT_MAX, description, sizeof(description));
  439.     filesize = avio_rl32(pb);
  440.     if (!filesize)
  441.         goto done;
  442.  
  443.     st = avformat_new_stream(s, NULL);
  444.     if (!st)
  445.         goto done;
  446.     av_dict_set(&st->metadata, "title", description, 0);
  447.     st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
  448.     st->codec->codec_id   = AV_CODEC_ID_MJPEG;
  449.     st->id = -1;
  450.     ret = av_get_packet(pb, &st->attached_pic, filesize);
  451.     if (ret < 0)
  452.         goto done;
  453.     st->attached_pic.stream_index = st->index;
  454.     st->attached_pic.flags       |= AV_PKT_FLAG_KEY;
  455.     st->disposition              |= AV_DISPOSITION_ATTACHED_PIC;
  456. done:
  457.     avio_seek(pb, pos + length, SEEK_SET);
  458. }
  459.  
  460. static void get_tag(AVFormatContext *s, AVIOContext *pb, const char *key, int type, int length)
  461. {
  462.     int buf_size;
  463.     char *buf;
  464.  
  465.     if (!strcmp(key, "WM/MediaThumbType")) {
  466.         avio_skip(pb, length);
  467.         return;
  468.     }
  469.  
  470.     buf_size = FFMAX(2*length, LEN_PRETTY_GUID) + 1;
  471.     buf = av_malloc(buf_size);
  472.     if (!buf)
  473.         return;
  474.  
  475.     if (type == 0 && length == 4) {
  476.         snprintf(buf, buf_size, "%"PRIi32, avio_rl32(pb));
  477.     } else if (type == 1) {
  478.         avio_get_str16le(pb, length, buf, buf_size);
  479.         if (!strlen(buf)) {
  480.            av_free(buf);
  481.            return;
  482.         }
  483.     } else if (type == 3 && length == 4) {
  484.         strcpy(buf, avio_rl32(pb) ? "true" : "false");
  485.     } else if (type == 4 && length == 8) {
  486.         int64_t num = avio_rl64(pb);
  487.         if (!strcmp(key, "WM/EncodingTime") ||
  488.             !strcmp(key, "WM/MediaOriginalBroadcastDateTime")) {
  489.             if (filetime_to_iso8601(buf, buf_size, num) < 0) {
  490.                 av_free(buf);
  491.                 return;
  492.             }
  493.         } else if (!strcmp(key, "WM/WMRVEncodeTime") ||
  494.                    !strcmp(key, "WM/WMRVEndTime")) {
  495.             if (crazytime_to_iso8601(buf, buf_size, num) < 0) {
  496.                 av_free(buf);
  497.                 return;
  498.             }
  499.         } else if (!strcmp(key, "WM/WMRVExpirationDate")) {
  500.             if (oledate_to_iso8601(buf, buf_size, num) < 0 ) {
  501.                 av_free(buf);
  502.                 return;
  503.             }
  504.         } else if (!strcmp(key, "WM/WMRVBitrate"))
  505.             snprintf(buf, buf_size, "%f", av_int2double(num));
  506.         else
  507.             snprintf(buf, buf_size, "%"PRIi64, num);
  508.     } else if (type == 5 && length == 2) {
  509.         snprintf(buf, buf_size, "%"PRIi16, avio_rl16(pb));
  510.     } else if (type == 6 && length == 16) {
  511.         ff_asf_guid guid;
  512.         avio_read(pb, guid, 16);
  513.         snprintf(buf, buf_size, PRI_PRETTY_GUID, ARG_PRETTY_GUID(guid));
  514.     } else if (type == 2 && !strcmp(key, "WM/Picture")) {
  515.         get_attachment(s, pb, length);
  516.         av_freep(&buf);
  517.         return;
  518.     } else {
  519.         av_freep(&buf);
  520.         av_log(s, AV_LOG_WARNING, "unsupported metadata entry; key:%s, type:%d, length:0x%x\n", key, type, length);
  521.         avio_skip(pb, length);
  522.         return;
  523.     }
  524.  
  525.     av_dict_set(&s->metadata, key, buf, 0);
  526.     av_freep(&buf);
  527. }
  528.  
  529. /**
  530.  * Parse metadata entries
  531.  */
  532. static void parse_legacy_attrib(AVFormatContext *s, AVIOContext *pb)
  533. {
  534.     ff_asf_guid guid;
  535.     int length, type;
  536.     while(!url_feof(pb)) {
  537.         char key[1024];
  538.         ff_get_guid(pb, &guid);
  539.         type   = avio_rl32(pb);
  540.         length = avio_rl32(pb);
  541.         if (!length)
  542.             break;
  543.         if (ff_guidcmp(&guid, ff_metadata_guid)) {
  544.             av_log(s, AV_LOG_WARNING, "unknown guid "FF_PRI_GUID", expected metadata_guid; "
  545.                    "remaining metadata entries ignored\n", FF_ARG_GUID(guid));
  546.             break;
  547.         }
  548.         avio_get_str16le(pb, INT_MAX, key, sizeof(key));
  549.         get_tag(s, pb, key, type, length);
  550.     }
  551.  
  552.     ff_metadata_conv(&s->metadata, NULL, ff_asf_metadata_conv);
  553. }
  554.  
  555. /**
  556.  * parse VIDEOINFOHEADER2 structure
  557.  * @return bytes consumed
  558.  */
  559. static int parse_videoinfoheader2(AVFormatContext *s, AVStream *st)
  560. {
  561.     WtvContext *wtv = s->priv_data;
  562.     AVIOContext *pb = wtv->pb;
  563.  
  564.     avio_skip(pb, 72);  // picture aspect ratio is unreliable
  565.     ff_get_bmp_header(pb, st, NULL);
  566.  
  567.     return 72 + 40;
  568. }
  569.  
  570. /**
  571.  * Parse MPEG1WAVEFORMATEX extradata structure
  572.  */
  573. static void parse_mpeg1waveformatex(AVStream *st)
  574. {
  575.     /* fwHeadLayer */
  576.     switch (AV_RL16(st->codec->extradata)) {
  577.     case 0x0001 : st->codec->codec_id = AV_CODEC_ID_MP1; break;
  578.     case 0x0002 : st->codec->codec_id = AV_CODEC_ID_MP2; break;
  579.     case 0x0004 : st->codec->codec_id = AV_CODEC_ID_MP3; break;
  580.     }
  581.  
  582.     st->codec->bit_rate = AV_RL32(st->codec->extradata + 2); /* dwHeadBitrate */
  583.  
  584.     /* dwHeadMode */
  585.     switch (AV_RL16(st->codec->extradata + 6)) {
  586.     case 1 :
  587.     case 2 :
  588.     case 4 : st->codec->channels       = 2;
  589.              st->codec->channel_layout = AV_CH_LAYOUT_STEREO;
  590.              break;
  591.     case 8 : st->codec->channels       = 1;
  592.              st->codec->channel_layout = AV_CH_LAYOUT_MONO;
  593.              break;
  594.     }
  595. }
  596.  
  597. /**
  598.  * Initialise stream
  599.  * @param st Stream to initialise, or NULL to create and initialise new stream
  600.  * @return NULL on error
  601.  */
  602. static AVStream * new_stream(AVFormatContext *s, AVStream *st, int sid, int codec_type)
  603. {
  604.     if (st) {
  605.         if (st->codec->extradata) {
  606.             av_freep(&st->codec->extradata);
  607.             st->codec->extradata_size = 0;
  608.         }
  609.     } else {
  610.         WtvStream *wst = av_mallocz(sizeof(WtvStream));
  611.         if (!wst)
  612.             return NULL;
  613.         st = avformat_new_stream(s, NULL);
  614.         if (!st) {
  615.             av_free(wst);
  616.             return NULL;
  617.         }
  618.         st->id = sid;
  619.         st->priv_data = wst;
  620.     }
  621.     st->codec->codec_type = codec_type;
  622.     st->need_parsing      = AVSTREAM_PARSE_FULL;
  623.     avpriv_set_pts_info(st, 64, 1, 10000000);
  624.     return st;
  625. }
  626.  
  627. /**
  628.  * parse Media Type structure and populate stream
  629.  * @param st         Stream, or NULL to create new stream
  630.  * @param mediatype  Mediatype GUID
  631.  * @param subtype    Subtype GUID
  632.  * @param formattype Format GUID
  633.  * @param size       Size of format buffer
  634.  * @return NULL on error
  635.  */
  636. static AVStream * parse_media_type(AVFormatContext *s, AVStream *st, int sid,
  637.                                    ff_asf_guid mediatype, ff_asf_guid subtype,
  638.                                    ff_asf_guid formattype, int size)
  639. {
  640.     WtvContext *wtv = s->priv_data;
  641.     AVIOContext *pb = wtv->pb;
  642.     if (!ff_guidcmp(subtype, ff_mediasubtype_cpfilters_processed) &&
  643.         !ff_guidcmp(formattype, ff_format_cpfilters_processed)) {
  644.         ff_asf_guid actual_subtype;
  645.         ff_asf_guid actual_formattype;
  646.  
  647.         if (size < 32) {
  648.             av_log(s, AV_LOG_WARNING, "format buffer size underflow\n");
  649.             avio_skip(pb, size);
  650.             return NULL;
  651.         }
  652.  
  653.         avio_skip(pb, size - 32);
  654.         ff_get_guid(pb, &actual_subtype);
  655.         ff_get_guid(pb, &actual_formattype);
  656.         avio_seek(pb, -size, SEEK_CUR);
  657.  
  658.         st = parse_media_type(s, st, sid, mediatype, actual_subtype, actual_formattype, size - 32);
  659.         avio_skip(pb, 32);
  660.         return st;
  661.     } else if (!ff_guidcmp(mediatype, ff_mediatype_audio)) {
  662.         st = new_stream(s, st, sid, AVMEDIA_TYPE_AUDIO);
  663.         if (!st)
  664.             return NULL;
  665.         if (!ff_guidcmp(formattype, ff_format_waveformatex)) {
  666.             int ret = ff_get_wav_header(pb, st->codec, size);
  667.             if (ret < 0)
  668.                 return NULL;
  669.         } else {
  670.             if (ff_guidcmp(formattype, ff_format_none))
  671.                 av_log(s, AV_LOG_WARNING, "unknown formattype:"FF_PRI_GUID"\n", FF_ARG_GUID(formattype));
  672.             avio_skip(pb, size);
  673.         }
  674.  
  675.         if (!memcmp(subtype + 4, (const uint8_t[]){FF_MEDIASUBTYPE_BASE_GUID}, 12)) {
  676.             st->codec->codec_id = ff_wav_codec_get_id(AV_RL32(subtype), st->codec->bits_per_coded_sample);
  677.         } else if (!ff_guidcmp(subtype, mediasubtype_mpeg1payload)) {
  678.             if (st->codec->extradata && st->codec->extradata_size >= 22)
  679.                 parse_mpeg1waveformatex(st);
  680.             else
  681.                 av_log(s, AV_LOG_WARNING, "MPEG1WAVEFORMATEX underflow\n");
  682.         } else {
  683.             st->codec->codec_id = ff_codec_guid_get_id(ff_codec_wav_guids, subtype);
  684.             if (st->codec->codec_id == AV_CODEC_ID_NONE)
  685.                 av_log(s, AV_LOG_WARNING, "unknown subtype:"FF_PRI_GUID"\n", FF_ARG_GUID(subtype));
  686.         }
  687.         return st;
  688.     } else if (!ff_guidcmp(mediatype, ff_mediatype_video)) {
  689.         st = new_stream(s, st, sid, AVMEDIA_TYPE_VIDEO);
  690.         if (!st)
  691.             return NULL;
  692.         if (!ff_guidcmp(formattype, format_videoinfo2)) {
  693.             int consumed = parse_videoinfoheader2(s, st);
  694.             avio_skip(pb, FFMAX(size - consumed, 0));
  695.         } else if (!ff_guidcmp(formattype, ff_format_mpeg2_video)) {
  696.             int consumed = parse_videoinfoheader2(s, st);
  697.             avio_skip(pb, FFMAX(size - consumed, 0));
  698.         } else {
  699.             if (ff_guidcmp(formattype, ff_format_none))
  700.                 av_log(s, AV_LOG_WARNING, "unknown formattype:"FF_PRI_GUID"\n", FF_ARG_GUID(formattype));
  701.             avio_skip(pb, size);
  702.         }
  703.  
  704.         if (!memcmp(subtype + 4, (const uint8_t[]){FF_MEDIASUBTYPE_BASE_GUID}, 12)) {
  705.             st->codec->codec_id = ff_codec_get_id(ff_codec_bmp_tags, AV_RL32(subtype));
  706.         } else {
  707.             st->codec->codec_id = ff_codec_guid_get_id(ff_video_guids, subtype);
  708.         }
  709.         if (st->codec->codec_id == AV_CODEC_ID_NONE)
  710.             av_log(s, AV_LOG_WARNING, "unknown subtype:"FF_PRI_GUID"\n", FF_ARG_GUID(subtype));
  711.         return st;
  712.     } else if (!ff_guidcmp(mediatype, mediatype_mpeg2_pes) &&
  713.                !ff_guidcmp(subtype, mediasubtype_dvb_subtitle)) {
  714.         st = new_stream(s, st, sid, AVMEDIA_TYPE_SUBTITLE);
  715.         if (!st)
  716.             return NULL;
  717.         if (ff_guidcmp(formattype, ff_format_none))
  718.             av_log(s, AV_LOG_WARNING, "unknown formattype:"FF_PRI_GUID"\n", FF_ARG_GUID(formattype));
  719.         avio_skip(pb, size);
  720.         st->codec->codec_id = AV_CODEC_ID_DVB_SUBTITLE;
  721.         return st;
  722.     } else if (!ff_guidcmp(mediatype, mediatype_mstvcaption) &&
  723.                (!ff_guidcmp(subtype, mediasubtype_teletext) || !ff_guidcmp(subtype, mediasubtype_dtvccdata))) {
  724.         st = new_stream(s, st, sid, AVMEDIA_TYPE_SUBTITLE);
  725.         if (!st)
  726.             return NULL;
  727.         if (ff_guidcmp(formattype, ff_format_none))
  728.             av_log(s, AV_LOG_WARNING, "unknown formattype:"FF_PRI_GUID"\n", FF_ARG_GUID(formattype));
  729.         avio_skip(pb, size);
  730.         st->codec->codec_id = !ff_guidcmp(subtype, mediasubtype_teletext) ? AV_CODEC_ID_DVB_TELETEXT : AV_CODEC_ID_EIA_608;
  731.         return st;
  732.     } else if (!ff_guidcmp(mediatype, mediatype_mpeg2_sections) &&
  733.                !ff_guidcmp(subtype, mediasubtype_mpeg2_sections)) {
  734.         if (ff_guidcmp(formattype, ff_format_none))
  735.             av_log(s, AV_LOG_WARNING, "unknown formattype:"FF_PRI_GUID"\n", FF_ARG_GUID(formattype));
  736.         avio_skip(pb, size);
  737.         return NULL;
  738.     }
  739.  
  740.     av_log(s, AV_LOG_WARNING, "unknown media type, mediatype:"FF_PRI_GUID
  741.                               ", subtype:"FF_PRI_GUID", formattype:"FF_PRI_GUID"\n",
  742.                               FF_ARG_GUID(mediatype), FF_ARG_GUID(subtype), FF_ARG_GUID(formattype));
  743.     avio_skip(pb, size);
  744.     return NULL;
  745. }
  746.  
  747. enum {
  748.     SEEK_TO_DATA = 0,
  749.     SEEK_TO_PTS,
  750. };
  751.  
  752. /**
  753.  * Parse WTV chunks
  754.  * @param mode SEEK_TO_DATA or SEEK_TO_PTS
  755.  * @param seekts timestamp
  756.  * @param[out] len_ptr Length of data chunk
  757.  * @return stream index of data chunk, or <0 on error
  758.  */
  759. static int parse_chunks(AVFormatContext *s, int mode, int64_t seekts, int *len_ptr)
  760. {
  761.     WtvContext *wtv = s->priv_data;
  762.     AVIOContext *pb = wtv->pb;
  763.     while (!url_feof(pb)) {
  764.         ff_asf_guid g;
  765.         int len, sid, consumed;
  766.  
  767.         ff_get_guid(pb, &g);
  768.         len = avio_rl32(pb);
  769.         if (len < 32)
  770.             break;
  771.         sid = avio_rl32(pb) & 0x7FFF;
  772.         avio_skip(pb, 8);
  773.         consumed = 32;
  774.  
  775.         if (!ff_guidcmp(g, ff_SBE2_STREAM_DESC_EVENT)) {
  776.             if (ff_find_stream_index(s, sid) < 0) {
  777.                 ff_asf_guid mediatype, subtype, formattype;
  778.                 int size;
  779.                 avio_skip(pb, 28);
  780.                 ff_get_guid(pb, &mediatype);
  781.                 ff_get_guid(pb, &subtype);
  782.                 avio_skip(pb, 12);
  783.                 ff_get_guid(pb, &formattype);
  784.                 size = avio_rl32(pb);
  785.                 parse_media_type(s, 0, sid, mediatype, subtype, formattype, size);
  786.                 consumed += 92 + size;
  787.             }
  788.         } else if (!ff_guidcmp(g, ff_stream2_guid)) {
  789.             int stream_index = ff_find_stream_index(s, sid);
  790.             if (stream_index >= 0 && s->streams[stream_index]->priv_data && !((WtvStream*)s->streams[stream_index]->priv_data)->seen_data) {
  791.                 ff_asf_guid mediatype, subtype, formattype;
  792.                 int size;
  793.                 avio_skip(pb, 12);
  794.                 ff_get_guid(pb, &mediatype);
  795.                 ff_get_guid(pb, &subtype);
  796.                 avio_skip(pb, 12);
  797.                 ff_get_guid(pb, &formattype);
  798.                 size = avio_rl32(pb);
  799.                 parse_media_type(s, s->streams[stream_index], sid, mediatype, subtype, formattype, size);
  800.                 consumed += 76 + size;
  801.             }
  802.         } else if (!ff_guidcmp(g, EVENTID_AudioDescriptorSpanningEvent) ||
  803.                    !ff_guidcmp(g, EVENTID_CtxADescriptorSpanningEvent) ||
  804.                    !ff_guidcmp(g, EVENTID_CSDescriptorSpanningEvent) ||
  805.                    !ff_guidcmp(g, EVENTID_StreamIDSpanningEvent) ||
  806.                    !ff_guidcmp(g, EVENTID_SubtitleSpanningEvent) ||
  807.                    !ff_guidcmp(g, EVENTID_TeletextSpanningEvent)) {
  808.             int stream_index = ff_find_stream_index(s, sid);
  809.             if (stream_index >= 0) {
  810.                 AVStream *st = s->streams[stream_index];
  811.                 uint8_t buf[258];
  812.                 const uint8_t *pbuf = buf;
  813.                 int buf_size;
  814.  
  815.                 avio_skip(pb, 8);
  816.                 consumed += 8;
  817.                 if (!ff_guidcmp(g, EVENTID_CtxADescriptorSpanningEvent) ||
  818.                     !ff_guidcmp(g, EVENTID_CSDescriptorSpanningEvent)) {
  819.                     avio_skip(pb, 6);
  820.                     consumed += 6;
  821.                 }
  822.  
  823.                 buf_size = FFMIN(len - consumed, sizeof(buf));
  824.                 avio_read(pb, buf, buf_size);
  825.                 consumed += buf_size;
  826.                 ff_parse_mpeg2_descriptor(s, st, 0, &pbuf, buf + buf_size, NULL, 0, 0, NULL);
  827.             }
  828.         } else if (!ff_guidcmp(g, EVENTID_AudioTypeSpanningEvent)) {
  829.             int stream_index = ff_find_stream_index(s, sid);
  830.             if (stream_index >= 0) {
  831.                 AVStream *st = s->streams[stream_index];
  832.                 int audio_type;
  833.                 avio_skip(pb, 8);
  834.                 audio_type = avio_r8(pb);
  835.                 if (audio_type == 2)
  836.                     st->disposition |= AV_DISPOSITION_HEARING_IMPAIRED;
  837.                 else if (audio_type == 3)
  838.                     st->disposition |= AV_DISPOSITION_VISUAL_IMPAIRED;
  839.                 consumed += 9;
  840.             }
  841.         } else if (!ff_guidcmp(g, EVENTID_DVBScramblingControlSpanningEvent)) {
  842.             int stream_index = ff_find_stream_index(s, sid);
  843.             if (stream_index >= 0) {
  844.                 avio_skip(pb, 12);
  845.                 if (avio_rl32(pb))
  846.                     av_log(s, AV_LOG_WARNING, "DVB scrambled stream detected (st:%d), decoding will likely fail\n", stream_index);
  847.                 consumed += 16;
  848.             }
  849.         } else if (!ff_guidcmp(g, EVENTID_LanguageSpanningEvent)) {
  850.             int stream_index = ff_find_stream_index(s, sid);
  851.             if (stream_index >= 0) {
  852.                 AVStream *st = s->streams[stream_index];
  853.                 uint8_t language[4];
  854.                 avio_skip(pb, 12);
  855.                 avio_read(pb, language, 3);
  856.                 if (language[0]) {
  857.                     language[3] = 0;
  858.                     av_dict_set(&st->metadata, "language", language, 0);
  859.                     if (!strcmp(language, "nar") || !strcmp(language, "NAR"))
  860.                         st->disposition |= AV_DISPOSITION_VISUAL_IMPAIRED;
  861.                 }
  862.                 consumed += 15;
  863.             }
  864.         } else if (!ff_guidcmp(g, ff_timestamp_guid)) {
  865.             int stream_index = ff_find_stream_index(s, sid);
  866.             if (stream_index >= 0) {
  867.                 avio_skip(pb, 8);
  868.                 wtv->pts = avio_rl64(pb);
  869.                 consumed += 16;
  870.                 if (wtv->pts == -1)
  871.                     wtv->pts = AV_NOPTS_VALUE;
  872.                 else {
  873.                     wtv->last_valid_pts = wtv->pts;
  874.                     if (wtv->epoch == AV_NOPTS_VALUE || wtv->pts < wtv->epoch)
  875.                         wtv->epoch = wtv->pts;
  876.                 if (mode == SEEK_TO_PTS && wtv->pts >= seekts) {
  877.                     avio_skip(pb, WTV_PAD8(len) - consumed);
  878.                     return 0;
  879.                 }
  880.                 }
  881.             }
  882.         } else if (!ff_guidcmp(g, ff_data_guid)) {
  883.             int stream_index = ff_find_stream_index(s, sid);
  884.             if (mode == SEEK_TO_DATA && stream_index >= 0 && len > 32 && s->streams[stream_index]->priv_data) {
  885.                 WtvStream *wst = s->streams[stream_index]->priv_data;
  886.                 wst->seen_data = 1;
  887.                 if (len_ptr) {
  888.                     *len_ptr = len;
  889.                 }
  890.                 return stream_index;
  891.             }
  892.         } else if (!ff_guidcmp(g, /* DSATTRIB_WMDRMProtectionInfo */ (const ff_asf_guid){0x83,0x95,0x74,0x40,0x9D,0x6B,0xEC,0x4E,0xB4,0x3C,0x67,0xA1,0x80,0x1E,0x1A,0x9B})) {
  893.             int stream_index = ff_find_stream_index(s, sid);
  894.             if (stream_index >= 0)
  895.                 av_log(s, AV_LOG_WARNING, "encrypted stream detected (st:%d), decoding will likely fail\n", stream_index);
  896.         } else if (
  897.             !ff_guidcmp(g, /* DSATTRIB_CAPTURE_STREAMTIME */ (const ff_asf_guid){0x14,0x56,0x1A,0x0C,0xCD,0x30,0x40,0x4F,0xBC,0xBF,0xD0,0x3E,0x52,0x30,0x62,0x07}) ||
  898.             !ff_guidcmp(g, /* DSATTRIB_PBDATAG_ATTRIBUTE */ (const ff_asf_guid){0x79,0x66,0xB5,0xE0,0xB9,0x12,0xCC,0x43,0xB7,0xDF,0x57,0x8C,0xAA,0x5A,0x7B,0x63}) ||
  899.             !ff_guidcmp(g, /* DSATTRIB_PicSampleSeq */ (const ff_asf_guid){0x02,0xAE,0x5B,0x2F,0x8F,0x7B,0x60,0x4F,0x82,0xD6,0xE4,0xEA,0x2F,0x1F,0x4C,0x99}) ||
  900.             !ff_guidcmp(g, /* DSATTRIB_TRANSPORT_PROPERTIES */ ff_DSATTRIB_TRANSPORT_PROPERTIES) ||
  901.             !ff_guidcmp(g, /* dvr_ms_vid_frame_rep_data */ (const ff_asf_guid){0xCC,0x32,0x64,0xDD,0x29,0xE2,0xDB,0x40,0x80,0xF6,0xD2,0x63,0x28,0xD2,0x76,0x1F}) ||
  902.             !ff_guidcmp(g, /* EVENTID_ChannelChangeSpanningEvent */ (const ff_asf_guid){0xE5,0xC5,0x67,0x90,0x5C,0x4C,0x05,0x42,0x86,0xC8,0x7A,0xFE,0x20,0xFE,0x1E,0xFA}) ||
  903.             !ff_guidcmp(g, /* EVENTID_ChannelInfoSpanningEvent */ (const ff_asf_guid){0x80,0x6D,0xF3,0x41,0x32,0x41,0xC2,0x4C,0xB1,0x21,0x01,0xA4,0x32,0x19,0xD8,0x1B}) ||
  904.             !ff_guidcmp(g, /* EVENTID_ChannelTypeSpanningEvent */ (const ff_asf_guid){0x51,0x1D,0xAB,0x72,0xD2,0x87,0x9B,0x48,0xBA,0x11,0x0E,0x08,0xDC,0x21,0x02,0x43}) ||
  905.             !ff_guidcmp(g, /* EVENTID_PIDListSpanningEvent */ (const ff_asf_guid){0x65,0x8F,0xFC,0x47,0xBB,0xE2,0x34,0x46,0x9C,0xEF,0xFD,0xBF,0xE6,0x26,0x1D,0x5C}) ||
  906.             !ff_guidcmp(g, /* EVENTID_SignalAndServiceStatusSpanningEvent */ (const ff_asf_guid){0xCB,0xC5,0x68,0x80,0x04,0x3C,0x2B,0x49,0xB4,0x7D,0x03,0x08,0x82,0x0D,0xCE,0x51}) ||
  907.             !ff_guidcmp(g, /* EVENTID_StreamTypeSpanningEvent */ (const ff_asf_guid){0xBC,0x2E,0xAF,0x82,0xA6,0x30,0x64,0x42,0xA8,0x0B,0xAD,0x2E,0x13,0x72,0xAC,0x60}) ||
  908.             !ff_guidcmp(g, (const ff_asf_guid){0x1E,0xBE,0xC3,0xC5,0x43,0x92,0xDC,0x11,0x85,0xE5,0x00,0x12,0x3F,0x6F,0x73,0xB9}) ||
  909.             !ff_guidcmp(g, (const ff_asf_guid){0x3B,0x86,0xA2,0xB1,0xEB,0x1E,0xC3,0x44,0x8C,0x88,0x1C,0xA3,0xFF,0xE3,0xE7,0x6A}) ||
  910.             !ff_guidcmp(g, (const ff_asf_guid){0x4E,0x7F,0x4C,0x5B,0xC4,0xD0,0x38,0x4B,0xA8,0x3E,0x21,0x7F,0x7B,0xBF,0x52,0xE7}) ||
  911.             !ff_guidcmp(g, (const ff_asf_guid){0x63,0x36,0xEB,0xFE,0xA1,0x7E,0xD9,0x11,0x83,0x08,0x00,0x07,0xE9,0x5E,0xAD,0x8D}) ||
  912.             !ff_guidcmp(g, (const ff_asf_guid){0x70,0xE9,0xF1,0xF8,0x89,0xA4,0x4C,0x4D,0x83,0x73,0xB8,0x12,0xE0,0xD5,0xF8,0x1E}) ||
  913.             !ff_guidcmp(g, ff_index_guid) ||
  914.             !ff_guidcmp(g, ff_sync_guid) ||
  915.             !ff_guidcmp(g, ff_stream1_guid) ||
  916.             !ff_guidcmp(g, (const ff_asf_guid){0xF7,0x10,0x02,0xB9,0xEE,0x7C,0xED,0x4E,0xBD,0x7F,0x05,0x40,0x35,0x86,0x18,0xA1})) {
  917.             //ignore known guids
  918.         } else
  919.             av_log(s, AV_LOG_WARNING, "unsupported chunk:"FF_PRI_GUID"\n", FF_ARG_GUID(g));
  920.  
  921.         avio_skip(pb, WTV_PAD8(len) - consumed);
  922.     }
  923.     return AVERROR_EOF;
  924. }
  925.  
  926. static int read_header(AVFormatContext *s)
  927. {
  928.     WtvContext *wtv = s->priv_data;
  929.     int root_sector, root_size;
  930.     uint8_t root[WTV_SECTOR_SIZE];
  931.     AVIOContext *pb;
  932.     int64_t timeline_pos;
  933.     int ret;
  934.  
  935.     wtv->epoch          =
  936.     wtv->pts            =
  937.     wtv->last_valid_pts = AV_NOPTS_VALUE;
  938.  
  939.     /* read root directory sector */
  940.     avio_skip(s->pb, 0x30);
  941.     root_size = avio_rl32(s->pb);
  942.     if (root_size > sizeof(root)) {
  943.         av_log(s, AV_LOG_ERROR, "root directory size exceeds sector size\n");
  944.         return AVERROR_INVALIDDATA;
  945.     }
  946.     avio_skip(s->pb, 4);
  947.     root_sector = avio_rl32(s->pb);
  948.  
  949.     seek_by_sector(s->pb, root_sector, 0);
  950.     root_size = avio_read(s->pb, root, root_size);
  951.     if (root_size < 0)
  952.         return AVERROR_INVALIDDATA;
  953.  
  954.     /* parse chunks up until first data chunk */
  955.     wtv->pb = wtvfile_open(s, root, root_size, ff_timeline_le16);
  956.     if (!wtv->pb) {
  957.         av_log(s, AV_LOG_ERROR, "timeline data missing\n");
  958.         return AVERROR_INVALIDDATA;
  959.     }
  960.  
  961.     ret = parse_chunks(s, SEEK_TO_DATA, 0, 0);
  962.     if (ret < 0)
  963.         return ret;
  964.     avio_seek(wtv->pb, -32, SEEK_CUR);
  965.  
  966.     timeline_pos = avio_tell(s->pb); // save before opening another file
  967.  
  968.     /* read metadata */
  969.     pb = wtvfile_open(s, root, root_size, ff_table_0_entries_legacy_attrib_le16);
  970.     if (pb) {
  971.         parse_legacy_attrib(s, pb);
  972.         wtvfile_close(pb);
  973.     }
  974.  
  975.     /* read seek index */
  976.     if (s->nb_streams) {
  977.         AVStream *st = s->streams[0];
  978.         pb = wtvfile_open(s, root, root_size, ff_table_0_entries_time_le16);
  979.         if (pb) {
  980.             while(1) {
  981.                 uint64_t timestamp = avio_rl64(pb);
  982.                 uint64_t frame_nb  = avio_rl64(pb);
  983.                 if (url_feof(pb))
  984.                     break;
  985.                 ff_add_index_entry(&wtv->index_entries, &wtv->nb_index_entries, &wtv->index_entries_allocated_size,
  986.                                    0, timestamp, frame_nb, 0, AVINDEX_KEYFRAME);
  987.             }
  988.             wtvfile_close(pb);
  989.  
  990.             if (wtv->nb_index_entries) {
  991.                 pb = wtvfile_open(s, root, root_size, ff_timeline_table_0_entries_Events_le16);
  992.                 if (pb) {
  993.                     int i;
  994.                     while (1) {
  995.                         uint64_t frame_nb = avio_rl64(pb);
  996.                         uint64_t position = avio_rl64(pb);
  997.                         if (url_feof(pb))
  998.                             break;
  999.                         for (i = wtv->nb_index_entries - 1; i >= 0; i--) {
  1000.                             AVIndexEntry *e = wtv->index_entries + i;
  1001.                             if (frame_nb > e->size)
  1002.                                 break;
  1003.                             if (position > e->pos)
  1004.                                 e->pos = position;
  1005.                         }
  1006.                     }
  1007.                     wtvfile_close(pb);
  1008.                     st->duration = wtv->index_entries[wtv->nb_index_entries - 1].timestamp;
  1009.                 }
  1010.             }
  1011.         }
  1012.     }
  1013.  
  1014.     avio_seek(s->pb, timeline_pos, SEEK_SET);
  1015.     return 0;
  1016. }
  1017.  
  1018. static int read_packet(AVFormatContext *s, AVPacket *pkt)
  1019. {
  1020.     WtvContext *wtv = s->priv_data;
  1021.     AVIOContext *pb = wtv->pb;
  1022.     int stream_index, len, ret;
  1023.  
  1024.     stream_index = parse_chunks(s, SEEK_TO_DATA, 0, &len);
  1025.     if (stream_index < 0)
  1026.         return stream_index;
  1027.  
  1028.     ret = av_get_packet(pb, pkt, len - 32);
  1029.     if (ret < 0)
  1030.         return ret;
  1031.     pkt->stream_index = stream_index;
  1032.     pkt->pts          = wtv->pts;
  1033.     avio_skip(pb, WTV_PAD8(len) - len);
  1034.     return 0;
  1035. }
  1036.  
  1037. static int read_seek(AVFormatContext *s, int stream_index,
  1038.                      int64_t ts, int flags)
  1039. {
  1040.     WtvContext *wtv = s->priv_data;
  1041.     AVIOContext *pb = wtv->pb;
  1042.     AVStream *st = s->streams[0];
  1043.     int64_t ts_relative;
  1044.     int i;
  1045.  
  1046.     if ((flags & AVSEEK_FLAG_FRAME) || (flags & AVSEEK_FLAG_BYTE))
  1047.         return AVERROR(ENOSYS);
  1048.  
  1049.     /* timestamp adjustment is required because wtv->pts values are absolute,
  1050.      * whereas AVIndexEntry->timestamp values are relative to epoch. */
  1051.     ts_relative = ts;
  1052.     if (wtv->epoch != AV_NOPTS_VALUE)
  1053.         ts_relative -= wtv->epoch;
  1054.  
  1055.     i = ff_index_search_timestamp(wtv->index_entries, wtv->nb_index_entries, ts_relative, flags);
  1056.     if (i < 0) {
  1057.         if (wtv->last_valid_pts == AV_NOPTS_VALUE || ts < wtv->last_valid_pts) {
  1058.             if (avio_seek(pb, 0, SEEK_SET) < 0)
  1059.                 return -1;
  1060.         } else if (st->duration != AV_NOPTS_VALUE && ts_relative > st->duration && wtv->nb_index_entries) {
  1061.             if (avio_seek(pb, wtv->index_entries[wtv->nb_index_entries - 1].pos, SEEK_SET) < 0)
  1062.                 return -1;
  1063.         }
  1064.         if (parse_chunks(s, SEEK_TO_PTS, ts, 0) < 0)
  1065.             return AVERROR(ERANGE);
  1066.         return 0;
  1067.     }
  1068.     if (avio_seek(pb, wtv->index_entries[i].pos, SEEK_SET) < 0)
  1069.         return -1;
  1070.     wtv->pts = wtv->index_entries[i].timestamp;
  1071.     if (wtv->epoch != AV_NOPTS_VALUE)
  1072.         wtv->pts += wtv->epoch;
  1073.     wtv->last_valid_pts = wtv->pts;
  1074.     return 0;
  1075. }
  1076.  
  1077. static int read_close(AVFormatContext *s)
  1078. {
  1079.     WtvContext *wtv = s->priv_data;
  1080.     av_freep(&wtv->index_entries);
  1081.     wtvfile_close(wtv->pb);
  1082.     return 0;
  1083. }
  1084.  
  1085. AVInputFormat ff_wtv_demuxer = {
  1086.     .name           = "wtv",
  1087.     .long_name      = NULL_IF_CONFIG_SMALL("Windows Television (WTV)"),
  1088.     .priv_data_size = sizeof(WtvContext),
  1089.     .read_probe     = read_probe,
  1090.     .read_header    = read_header,
  1091.     .read_packet    = read_packet,
  1092.     .read_seek      = read_seek,
  1093.     .read_close     = read_close,
  1094.     .flags          = AVFMT_SHOW_IDS,
  1095. };
  1096.