FFmpeg: libavformat/wtvdec.c Source File

00001 /*
00002  * Windows Television (WTV) demuxer
00003  * Copyright (c) 2010-2011 Peter Ross <pross@xvid.org>
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * FFmpeg is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00028 #include "libavutil/intreadwrite.h"
00029 #include "libavutil/intfloat_readwrite.h"
00030 #include "avformat.h"
00031 #include "internal.h"
00032 #include "wtv.h"
00033 #include "mpegts.h"
00034 #include <strings.h>
00035 
00036 /* Macros for formating GUIDs */
00037 #define PRI_PRETTY_GUID \
00038     "%08x-%04x-%04x-%02x%02x%02x%02x%02x%02x%02x%02x"
00039 #define ARG_PRETTY_GUID(g) \
00040     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]
00041 #define LEN_PRETTY_GUID 34
00042 
00043 /*
00044  *
00045  * File system routines
00046  *
00047  */
00048 
00049 typedef struct {
00050     AVIOContext *pb_filesystem;  
00052     int sector_bits;     
00053     uint32_t *sectors;   
00054     int nb_sectors;      
00056     int error;
00057     int64_t position;
00058     int64_t length;
00059 } WtvFile;
00060 
00064 static int wtvfile_read_packet(void *opaque, uint8_t *buf, int buf_size)
00065 {
00066     WtvFile *wf = opaque;
00067     AVIOContext *pb = wf->pb_filesystem;
00068     int nread = 0;
00069 
00070     if (wf->error || pb->error)
00071         return -1;
00072     if (wf->position >= wf->length || url_feof(pb))
00073         return 0;
00074 
00075     buf_size = FFMIN(buf_size, wf->length - wf->position);
00076     while(nread < buf_size) {
00077         int n;
00078         int remaining_in_sector = (1 << wf->sector_bits) - (wf->position & ((1 << wf->sector_bits) - 1));
00079         int read_request        = FFMIN(buf_size - nread, remaining_in_sector);
00080 
00081         n = avio_read(pb, buf, read_request);
00082         if (n <= 0)
00083             break;
00084         nread += n;
00085         buf += n;
00086         wf->position += n;
00087         if (n == remaining_in_sector) {
00088             int i = wf->position >> wf->sector_bits;
00089             if (i >= wf->nb_sectors ||
00090                 (wf->sectors[i] != wf->sectors[i - 1] + (1 << (wf->sector_bits - WTV_SECTOR_BITS)) &&
00091                 avio_seek(pb, (int64_t)wf->sectors[i] << WTV_SECTOR_BITS, SEEK_SET) < 0)) {
00092                 wf->error = 1;
00093                 break;
00094             }
00095         }
00096     }
00097     return nread;
00098 }
00099 
00103 static int64_t wtvfile_seek(void *opaque, int64_t offset, int whence)
00104 {
00105     WtvFile *wf = opaque;
00106     AVIOContext *pb = wf->pb_filesystem;
00107 
00108     if (whence == AVSEEK_SIZE)
00109         return wf->length;
00110     else if (whence == SEEK_CUR)
00111         offset = wf->position + offset;
00112     else if (whence == SEEK_END)
00113         offset = wf->length;
00114 
00115     wf->error = offset < 0 || offset >= wf->length ||
00116                 avio_seek(pb, ((int64_t)wf->sectors[offset >> wf->sector_bits] << WTV_SECTOR_BITS)
00117                               + (offset & ((1 << wf->sector_bits) - 1)), SEEK_SET) < 0;
00118     wf->position = offset;
00119     return offset;
00120 }
00121 
00129 static int read_ints(AVIOContext *pb, uint32_t *data, int count)
00130 {
00131     int i, total = 0;
00132     for (i = 0; i < count; i++) {
00133         if ((data[total] = avio_rl32(pb)))
00134            total++;
00135     }
00136     return total;
00137 }
00138 
00146 static AVIOContext * wtvfile_open_sector(int first_sector, uint64_t length, int depth, AVFormatContext *s)
00147 {
00148     AVIOContext *pb;
00149     WtvFile *wf;
00150     uint8_t *buffer;
00151 
00152     if (avio_seek(s->pb, first_sector << WTV_SECTOR_BITS, SEEK_SET) < 0)
00153         return NULL;
00154 
00155     wf = av_mallocz(sizeof(WtvFile));
00156     if (!wf)
00157         return NULL;
00158 
00159     if (depth == 0) {
00160         wf->sectors = av_malloc(sizeof(uint32_t));
00161         if (!wf->sectors) {
00162             av_free(wf);
00163             return NULL;
00164         }
00165         wf->sectors[0]  = first_sector;
00166         wf->nb_sectors  = 1;
00167         wf->sector_bits = WTV_SECTOR_BITS;
00168     } else if (depth == 1) {
00169         wf->sectors = av_malloc(WTV_SECTOR_SIZE);
00170         if (!wf->sectors) {
00171             av_free(wf);
00172             return NULL;
00173         }
00174         wf->nb_sectors  = read_ints(s->pb, wf->sectors, WTV_SECTOR_SIZE / 4);
00175         wf->sector_bits = length & (1ULL<<63) ? WTV_SECTOR_BITS : WTV_BIGSECTOR_BITS;
00176     } else if (depth == 2) {
00177         uint32_t sectors1[WTV_SECTOR_SIZE / 4];
00178         int nb_sectors1 = read_ints(s->pb, sectors1, WTV_SECTOR_SIZE / 4);
00179         int i;
00180 
00181         wf->sectors = av_malloc(nb_sectors1 << WTV_SECTOR_BITS);
00182         if (!wf->sectors) {
00183             av_free(wf);
00184             return NULL;
00185         }
00186         wf->nb_sectors = 0;
00187         for (i = 0; i < nb_sectors1; i++) {
00188             if (avio_seek(s->pb, (int64_t)sectors1[i] << WTV_SECTOR_BITS, SEEK_SET) < 0)
00189                 break;
00190             wf->nb_sectors += read_ints(s->pb, wf->sectors + i * WTV_SECTOR_SIZE / 4, WTV_SECTOR_SIZE / 4);
00191         }
00192         wf->sector_bits = length & (1ULL<<63) ? WTV_SECTOR_BITS : WTV_BIGSECTOR_BITS;
00193     } else {
00194         av_log(s, AV_LOG_ERROR, "unsupported file allocation table depth (0x%x)\n", depth);
00195         av_free(wf);
00196         return NULL;
00197     }
00198 
00199     if (!wf->nb_sectors) {
00200         av_free(wf->sectors);
00201         av_free(wf);
00202         return NULL;
00203     }
00204 
00205     /* check length */
00206     length &= 0xFFFFFFFFFFFF;
00207     if (length > ((int64_t)wf->nb_sectors << wf->sector_bits)) {
00208         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);
00209         length = (int64_t)wf->nb_sectors <<  wf->sector_bits;
00210     }
00211     wf->length = length;
00212 
00213     /* seek to intial sector */
00214     wf->position = 0;
00215     if (avio_seek(s->pb, (int64_t)wf->sectors[0] << WTV_SECTOR_BITS, SEEK_SET) < 0) {
00216         av_free(wf->sectors);
00217         av_free(wf);
00218         return NULL;
00219     }
00220 
00221     wf->pb_filesystem = s->pb;
00222     buffer = av_malloc(1 << wf->sector_bits);
00223     if (!buffer) {
00224         av_free(wf->sectors);
00225         av_free(wf);
00226         return NULL;
00227     }
00228 
00229     pb = avio_alloc_context(buffer, 1 << wf->sector_bits, 0, wf,
00230                            wtvfile_read_packet, NULL, wtvfile_seek);
00231     if (!pb) {
00232         av_free(buffer);
00233         av_free(wf->sectors);
00234         av_free(wf);
00235     }
00236     return pb;
00237 }
00238 
00247 static AVIOContext * wtvfile_open2(AVFormatContext *s, const uint8_t *buf, int buf_size, const uint8_t *filename, int filename_size)
00248 {
00249     const uint8_t *buf_end = buf + buf_size;
00250 
00251     while(buf + 48 <= buf_end) {
00252         int dir_length, name_size, first_sector, depth;
00253         uint64_t file_length;
00254         const uint8_t *name;
00255         if (ff_guidcmp(buf, ff_dir_entry_guid)) {
00256             av_log(s, AV_LOG_ERROR, "unknown guid "FF_PRI_GUID", expected dir_entry_guid; "
00257                    "remaining directory entries ignored\n", FF_ARG_GUID(buf));
00258             break;
00259         }
00260         dir_length  = AV_RL16(buf + 16);
00261         file_length = AV_RL64(buf + 24);
00262         name_size   = 2 * AV_RL32(buf + 32);
00263         if (buf + 48 + name_size > buf_end) {
00264             av_log(s, AV_LOG_ERROR, "filename exceeds buffer size; remaining directory entries ignored\n");
00265             break;
00266         }
00267         first_sector = AV_RL32(buf + 40 + name_size);
00268         depth        = AV_RL32(buf + 44 + name_size);
00269 
00270         /* compare file name; test optional null terminator */
00271         name = buf + 40;
00272         if (name_size >= filename_size &&
00273             !memcmp(name, filename, filename_size) &&
00274             (name_size < filename_size + 2 || !AV_RN16(name + filename_size)))
00275             return wtvfile_open_sector(first_sector, file_length, depth, s);
00276 
00277         buf += dir_length;
00278     }
00279     return 0;
00280 }
00281 
00282 #define wtvfile_open(s, buf, buf_size, filename) \
00283     wtvfile_open2(s, buf, buf_size, filename, sizeof(filename))
00284 
00288 static void wtvfile_close(AVIOContext *pb)
00289 {
00290     WtvFile *wf = pb->opaque;
00291     av_free(wf->sectors);
00292     av_free(pb);
00293 }
00294 
00295 /*
00296  *
00297  * Main demuxer
00298  *
00299  */
00300 
00301 typedef struct {
00302     int seen_data;
00303 } WtvStream;
00304 
00305 typedef struct {
00306     AVIOContext *pb;       
00307     int64_t epoch;
00308     int64_t pts;             
00309     int64_t last_valid_pts;  
00311     /* maintain private seek index, as the AVIndexEntry->pos is relative to the
00312        start of the 'timeline' file, not the file system (AVFormatContext->pb) */
00313     AVIndexEntry *index_entries;
00314     int nb_index_entries;
00315     unsigned int index_entries_allocated_size;
00316 } WtvContext;
00317 
00318 /* WTV GUIDs */
00319 static const ff_asf_guid metadata_guid =
00320     {0x5A,0xFE,0xD7,0x6D,0xC8,0x1D,0x8F,0x4A,0x99,0x22,0xFA,0xB1,0x1C,0x38,0x14,0x53};
00321 static const ff_asf_guid stream2_guid =
00322     {0xA2,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D};
00323 static const ff_asf_guid EVENTID_SubtitleSpanningEvent =
00324     {0x48,0xC0,0xCE,0x5D,0xB9,0xD0,0x63,0x41,0x87,0x2C,0x4F,0x32,0x22,0x3B,0xE8,0x8A};
00325 static const ff_asf_guid EVENTID_LanguageSpanningEvent =
00326     {0x6D,0x66,0x92,0xE2,0x02,0x9C,0x8D,0x44,0xAA,0x8D,0x78,0x1A,0x93,0xFD,0xC3,0x95};
00327 static const ff_asf_guid EVENTID_AudioDescriptorSpanningEvent =
00328     {0x1C,0xD4,0x7B,0x10,0xDA,0xA6,0x91,0x46,0x83,0x69,0x11,0xB2,0xCD,0xAA,0x28,0x8E};
00329 static const ff_asf_guid EVENTID_CtxADescriptorSpanningEvent =
00330     {0xE6,0xA2,0xB4,0x3A,0x47,0x42,0x34,0x4B,0x89,0x6C,0x30,0xAF,0xA5,0xD2,0x1C,0x24};
00331 static const ff_asf_guid EVENTID_CSDescriptorSpanningEvent =
00332     {0xD9,0x79,0xE7,0xEf,0xF0,0x97,0x86,0x47,0x80,0x0D,0x95,0xCF,0x50,0x5D,0xDC,0x66};
00333 static const ff_asf_guid EVENTID_DVBScramblingControlSpanningEvent =
00334     {0xC4,0xE1,0xD4,0x4B,0xA1,0x90,0x09,0x41,0x82,0x36,0x27,0xF0,0x0E,0x7D,0xCC,0x5B};
00335 static const ff_asf_guid EVENTID_StreamIDSpanningEvent =
00336     {0x68,0xAB,0xF1,0xCA,0x53,0xE1,0x41,0x4D,0xA6,0xB3,0xA7,0xC9,0x98,0xDB,0x75,0xEE};
00337 static const ff_asf_guid EVENTID_TeletextSpanningEvent =
00338     {0x50,0xD9,0x99,0x95,0x33,0x5F,0x17,0x46,0xAF,0x7C,0x1E,0x54,0xB5,0x10,0xDA,0xA3};
00339 static const ff_asf_guid EVENTID_AudioTypeSpanningEvent =
00340     {0xBE,0xBF,0x1C,0x50,0x49,0xB8,0xCE,0x42,0x9B,0xE9,0x3D,0xB8,0x69,0xFB,0x82,0xB3};
00341 
00342 /* Windows media GUIDs */
00343 
00344 /* Media types */
00345 static const ff_asf_guid mediasubtype_mpeg1payload =
00346     {0x81,0xEB,0x36,0xE4,0x4F,0x52,0xCE,0x11,0x9F,0x53,0x00,0x20,0xAF,0x0B,0xA7,0x70};
00347 static const ff_asf_guid mediatype_mpeg2_sections =
00348     {0x6C,0x17,0x5F,0x45,0x06,0x4B,0xCE,0x47,0x9A,0xEF,0x8C,0xAE,0xF7,0x3D,0xF7,0xB5};
00349 static const ff_asf_guid mediatype_mpeg2_pes =
00350     {0x20,0x80,0x6D,0xE0,0x46,0xDB,0xCF,0x11,0xB4,0xD1,0x00,0x80,0x5F,0x6C,0xBB,0xEA};
00351 static const ff_asf_guid mediatype_mstvcaption =
00352     {0x89,0x8A,0x8B,0xB8,0x49,0xB0,0x80,0x4C,0xAD,0xCF,0x58,0x98,0x98,0x5E,0x22,0xC1};
00353 
00354 /* Media subtypes */
00355 static const ff_asf_guid mediasubtype_cpfilters_processed =
00356     {0x28,0xBD,0xAD,0x46,0xD0,0x6F,0x96,0x47,0x93,0xB2,0x15,0x5C,0x51,0xDC,0x04,0x8D};
00357 static const ff_asf_guid mediasubtype_dvb_subtitle =
00358     {0xC3,0xCB,0xFF,0x34,0xB3,0xD5,0x71,0x41,0x90,0x02,0xD4,0xC6,0x03,0x01,0x69,0x7F};
00359 static const ff_asf_guid mediasubtype_teletext =
00360     {0xE3,0x76,0x2A,0xF7,0x0A,0xEB,0xD0,0x11,0xAC,0xE4,0x00,0x00,0xC0,0xCC,0x16,0xBA};
00361 static const ff_asf_guid mediasubtype_dtvccdata =
00362     {0xAA,0xDD,0x2A,0xF5,0xF0,0x36,0xF5,0x43,0x95,0xEA,0x6D,0x86,0x64,0x84,0x26,0x2A};
00363 static const ff_asf_guid mediasubtype_mpeg2_sections =
00364     {0x79,0x85,0x9F,0x4A,0xF8,0x6B,0x92,0x43,0x8A,0x6D,0xD2,0xDD,0x09,0xFA,0x78,0x61};
00365 
00366 /* Formats */
00367 static const ff_asf_guid format_cpfilters_processed =
00368     {0x6F,0xB3,0x39,0x67,0x5F,0x1D,0xC2,0x4A,0x81,0x92,0x28,0xBB,0x0E,0x73,0xD1,0x6A};
00369 static const ff_asf_guid format_waveformatex =
00370     {0x81,0x9F,0x58,0x05,0x56,0xC3,0xCE,0x11,0xBF,0x01,0x00,0xAA,0x00,0x55,0x59,0x5A};
00371 static const ff_asf_guid format_videoinfo2 =
00372     {0xA0,0x76,0x2A,0xF7,0x0A,0xEB,0xD0,0x11,0xAC,0xE4,0x00,0x00,0xC0,0xCC,0x16,0xBA};
00373 static const ff_asf_guid format_mpeg2_video =
00374     {0xE3,0x80,0x6D,0xE0,0x46,0xDB,0xCF,0x11,0xB4,0xD1,0x00,0x80,0x5F,0x6C,0xBB,0xEA};
00375 
00376 static int read_probe(AVProbeData *p)
00377 {
00378     return ff_guidcmp(p->buf, ff_wtv_guid) ? 0 : AVPROBE_SCORE_MAX;
00379 }
00380 
00384 static void filetime_to_iso8601(char *buf, int buf_size, int64_t value)
00385 {
00386     time_t t = (value / 10000000LL) - 11644473600LL;
00387     strftime(buf, buf_size, "%Y-%m-%d %H:%M:%S", gmtime(&t));
00388 }
00389 
00393 static void crazytime_to_iso8601(char *buf, int buf_size, int64_t value)
00394 {
00395     time_t t = (value / 10000000LL) - 719162LL*86400LL;
00396     strftime(buf, buf_size, "%Y-%m-%d %H:%M:%S", gmtime(&t));
00397 }
00398 
00403 static int oledate_to_iso8601(char *buf, int buf_size, int64_t value)
00404 {
00405     time_t t = (av_int2dbl(value) - 25569.0) * 86400;
00406     struct tm *result= gmtime(&t);
00407     if (!result)
00408         return -1;
00409     strftime(buf, buf_size, "%Y-%m-%d %H:%M:%S", result);
00410     return 0;
00411 }
00412 
00413 static void get_attachment(AVFormatContext *s, AVIOContext *pb, int length)
00414 {
00415     char mime[1024];
00416     char description[1024];
00417     unsigned int filesize;
00418     AVStream *st;
00419     int64_t pos = avio_tell(pb);
00420 
00421     avio_get_str16le(pb, INT_MAX, mime, sizeof(mime));
00422     if (strcmp(mime, "image/jpeg"))
00423         goto done;
00424 
00425     avio_r8(pb);
00426     avio_get_str16le(pb, INT_MAX, description, sizeof(description));
00427     filesize = avio_rl32(pb);
00428     if (!filesize)
00429         goto done;
00430 
00431     st = av_new_stream(s, 0);
00432     if (!st)
00433         goto done;
00434     av_dict_set(&st->metadata, "title", description, 0);
00435     st->codec->codec_id   = CODEC_ID_MJPEG;
00436     st->codec->codec_type = AVMEDIA_TYPE_ATTACHMENT;
00437     st->codec->extradata  = av_mallocz(filesize);
00438     if (!st->codec->extradata)
00439         goto done;
00440     st->codec->extradata_size = filesize;
00441     avio_read(pb, st->codec->extradata, filesize);
00442 done:
00443     avio_seek(pb, pos + length, SEEK_SET);
00444 }
00445 
00446 static void get_tag(AVFormatContext *s, AVIOContext *pb, const char *key, int type, int length)
00447 {
00448     int buf_size = FFMAX(2*length, LEN_PRETTY_GUID) + 1;
00449     char *buf = av_malloc(buf_size);
00450     if (!buf)
00451         return;
00452 
00453     if (type == 0 && length == 4) {
00454         snprintf(buf, buf_size, "%"PRIi32, avio_rl32(pb));
00455     } else if (type == 1) {
00456         avio_get_str16le(pb, length, buf, buf_size);
00457         if (!strlen(buf)) {
00458            av_free(buf);
00459            return;
00460         }
00461     } else if (type == 3 && length == 4) {
00462         strcpy(buf, avio_rl32(pb) ? "true" : "false");
00463     } else if (type == 4 && length == 8) {
00464         int64_t num = avio_rl64(pb);
00465         if (!strcmp(key, "WM/EncodingTime") ||
00466             !strcmp(key, "WM/MediaOriginalBroadcastDateTime"))
00467             filetime_to_iso8601(buf, buf_size, num);
00468         else if (!strcmp(key, "WM/WMRVEncodeTime") ||
00469                  !strcmp(key, "WM/WMRVEndTime"))
00470             crazytime_to_iso8601(buf, buf_size, num);
00471         else if (!strcmp(key, "WM/WMRVExpirationDate")) {
00472             if (oledate_to_iso8601(buf, buf_size, num) < 0 ) {
00473                 av_free(buf);
00474                 return;
00475             }
00476         } else if (!strcmp(key, "WM/WMRVBitrate"))
00477             snprintf(buf, buf_size, "%f", av_int2dbl(num));
00478         else
00479             snprintf(buf, buf_size, "%"PRIi64, num);
00480     } else if (type == 5 && length == 2) {
00481         snprintf(buf, buf_size, "%"PRIi16, avio_rl16(pb));
00482     } else if (type == 6 && length == 16) {
00483         ff_asf_guid guid;
00484         avio_read(pb, guid, 16);
00485         snprintf(buf, buf_size, PRI_PRETTY_GUID, ARG_PRETTY_GUID(guid));
00486     } else if (type == 2 && !strcmp(key, "WM/Picture")) {
00487         get_attachment(s, pb, length);
00488         av_freep(&buf);
00489         return;
00490     } else {
00491         av_freep(&buf);
00492         av_log(s, AV_LOG_WARNING, "unsupported metadata entry; key:%s, type:%d, length:0x%x\n", key, type, length);
00493         avio_skip(pb, length);
00494         return;
00495     }
00496 
00497     av_dict_set(&s->metadata, key, buf, 0);
00498     av_freep(&buf);
00499 }
00500 
00504 static void parse_legacy_attrib(AVFormatContext *s, AVIOContext *pb)
00505 {
00506     ff_asf_guid guid;
00507     int length, type;
00508     while(!url_feof(pb)) {
00509         char key[1024];
00510         ff_get_guid(pb, &guid);
00511         type   = avio_rl32(pb);
00512         length = avio_rl32(pb);
00513         if (!length)
00514             break;
00515         if (ff_guidcmp(&guid, metadata_guid)) {
00516             av_log(s, AV_LOG_WARNING, "unknown guid "FF_PRI_GUID", expected metadata_guid; "
00517                    "remaining metadata entries ignored\n", FF_ARG_GUID(guid));
00518             break;
00519         }
00520         avio_get_str16le(pb, INT_MAX, key, sizeof(key));
00521         get_tag(s, pb, key, type, length);
00522     }
00523 
00524     ff_metadata_conv(&s->metadata, NULL, ff_asf_metadata_conv);
00525 }
00526 
00531 static int parse_videoinfoheader2(AVFormatContext *s, AVStream *st)
00532 {
00533     WtvContext *wtv = s->priv_data;
00534     AVIOContext *pb = wtv->pb;
00535 
00536     avio_skip(pb, 72);  // picture aspect ratio is unreliable
00537     ff_get_bmp_header(pb, st);
00538 
00539     return 72 + 40;
00540 }
00541 
00545 static void parse_mpeg1waveformatex(AVStream *st)
00546 {
00547     /* fwHeadLayer */
00548     switch (AV_RL16(st->codec->extradata)) {
00549     case 0x0001 : st->codec->codec_id = CODEC_ID_MP1; break;
00550     case 0x0002 : st->codec->codec_id = CODEC_ID_MP2; break;
00551     case 0x0004 : st->codec->codec_id = CODEC_ID_MP3; break;
00552     }
00553 
00554     st->codec->bit_rate = AV_RL32(st->codec->extradata + 2); /* dwHeadBitrate */
00555 
00556     /* dwHeadMode */
00557     switch (AV_RL16(st->codec->extradata + 6)) {
00558     case 1 : case 2 : case 4 : st->codec->channels = 2; break;
00559     case 8 :                   st->codec->channels = 1; break;
00560     }
00561 }
00562 
00568 static AVStream * new_stream(AVFormatContext *s, AVStream *st, int sid, int codec_type)
00569 {
00570     if (st) {
00571         if (st->codec->extradata) {
00572             av_freep(&st->codec->extradata);
00573             st->codec->extradata_size = 0;
00574         }
00575     } else {
00576         WtvStream *wst = av_mallocz(sizeof(WtvStream));
00577         if (!wst)
00578             return NULL;
00579         st = av_new_stream(s, sid);
00580         if (!st)
00581             return NULL;
00582         st->priv_data = wst;
00583     }
00584     st->codec->codec_type = codec_type;
00585     st->need_parsing      = AVSTREAM_PARSE_FULL;
00586     av_set_pts_info(st, 64, 1, 10000000);
00587     return st;
00588 }
00589 
00599 static AVStream * parse_media_type(AVFormatContext *s, AVStream *st, int sid,
00600                                    ff_asf_guid mediatype, ff_asf_guid subtype,
00601                                    ff_asf_guid formattype, int size)
00602 {
00603     WtvContext *wtv = s->priv_data;
00604     AVIOContext *pb = wtv->pb;
00605     if (!ff_guidcmp(subtype, mediasubtype_cpfilters_processed) &&
00606         !ff_guidcmp(formattype, format_cpfilters_processed)) {
00607         ff_asf_guid actual_subtype;
00608         ff_asf_guid actual_formattype;
00609 
00610         if (size < 32) {
00611             av_log(s, AV_LOG_WARNING, "format buffer size underflow\n");
00612             avio_skip(pb, size);
00613             return NULL;
00614         }
00615 
00616         avio_skip(pb, size - 32);
00617         ff_get_guid(pb, &actual_subtype);
00618         ff_get_guid(pb, &actual_formattype);
00619         avio_seek(pb, -size, SEEK_CUR);
00620 
00621         st = parse_media_type(s, st, sid, mediatype, actual_subtype, actual_formattype, size - 32);
00622         avio_skip(pb, 32);
00623         return st;
00624     } else if (!ff_guidcmp(mediatype, ff_mediatype_audio)) {
00625         st = new_stream(s, st, sid, AVMEDIA_TYPE_AUDIO);
00626         if (!st)
00627             return NULL;
00628         if (!ff_guidcmp(formattype, format_waveformatex)) {
00629             int ret = ff_get_wav_header(pb, st->codec, size);
00630             if (ret < 0)
00631                 return NULL;
00632         } else {
00633             if (ff_guidcmp(formattype, ff_format_none))
00634                 av_log(s, AV_LOG_WARNING, "unknown formattype:"FF_PRI_GUID"\n", FF_ARG_GUID(formattype));
00635             avio_skip(pb, size);
00636         }
00637 
00638         if (!memcmp(subtype + 4, (const uint8_t[]){FF_MEDIASUBTYPE_BASE_GUID}, 12)) {
00639             st->codec->codec_id = ff_wav_codec_get_id(AV_RL32(subtype), st->codec->bits_per_coded_sample);
00640         } else if (!ff_guidcmp(subtype, mediasubtype_mpeg1payload)) {
00641             if (st->codec->extradata && st->codec->extradata_size >= 22)
00642                 parse_mpeg1waveformatex(st);
00643             else
00644                 av_log(s, AV_LOG_WARNING, "MPEG1WAVEFORMATEX underflow\n");
00645         } else {
00646             st->codec->codec_id = ff_codec_guid_get_id(ff_codec_wav_guids, subtype);
00647             if (st->codec->codec_id == CODEC_ID_NONE)
00648                 av_log(s, AV_LOG_WARNING, "unknown subtype:"FF_PRI_GUID"\n", FF_ARG_GUID(subtype));
00649         }
00650         return st;
00651     } else if (!ff_guidcmp(mediatype, ff_mediatype_video)) {
00652         st = new_stream(s, st, sid, AVMEDIA_TYPE_VIDEO);
00653         if (!st)
00654             return NULL;
00655         if (!ff_guidcmp(formattype, format_videoinfo2)) {
00656             int consumed = parse_videoinfoheader2(s, st);
00657             avio_skip(pb, FFMAX(size - consumed, 0));
00658         } else if (!ff_guidcmp(formattype, format_mpeg2_video)) {
00659             int consumed = parse_videoinfoheader2(s, st);
00660             avio_skip(pb, FFMAX(size - consumed, 0));
00661         } else {
00662             if (ff_guidcmp(formattype, ff_format_none))
00663                 av_log(s, AV_LOG_WARNING, "unknown formattype:"FF_PRI_GUID"\n", FF_ARG_GUID(formattype));
00664             avio_skip(pb, size);
00665         }
00666 
00667         if (!memcmp(subtype + 4, (const uint8_t[]){FF_MEDIASUBTYPE_BASE_GUID}, 12)) {
00668             st->codec->codec_id = ff_codec_get_id(ff_codec_bmp_tags, AV_RL32(subtype));
00669         } else {
00670             st->codec->codec_id = ff_codec_guid_get_id(ff_video_guids, subtype);
00671         }
00672         if (st->codec->codec_id == CODEC_ID_NONE)
00673             av_log(s, AV_LOG_WARNING, "unknown subtype:"FF_PRI_GUID"\n", FF_ARG_GUID(subtype));
00674         return st;
00675     } else if (!ff_guidcmp(mediatype, mediatype_mpeg2_pes) &&
00676                !ff_guidcmp(subtype, mediasubtype_dvb_subtitle)) {
00677         st = new_stream(s, st, sid, AVMEDIA_TYPE_SUBTITLE);
00678         if (!st)
00679             return NULL;
00680         if (ff_guidcmp(formattype, ff_format_none))
00681             av_log(s, AV_LOG_WARNING, "unknown formattype:"FF_PRI_GUID"\n", FF_ARG_GUID(formattype));
00682         avio_skip(pb, size);
00683         st->codec->codec_id = CODEC_ID_DVB_SUBTITLE;
00684         return st;
00685     } else if (!ff_guidcmp(mediatype, mediatype_mstvcaption) &&
00686                (!ff_guidcmp(subtype, mediasubtype_teletext) || !ff_guidcmp(subtype, mediasubtype_dtvccdata))) {
00687         st = new_stream(s, st, sid, AVMEDIA_TYPE_SUBTITLE);
00688         if (!st)
00689             return NULL;
00690         if (ff_guidcmp(formattype, ff_format_none))
00691             av_log(s, AV_LOG_WARNING, "unknown formattype:"FF_PRI_GUID"\n", FF_ARG_GUID(formattype));
00692         avio_skip(pb, size);
00693         st->codec->codec_id   = CODEC_ID_DVB_TELETEXT;
00694         return st;
00695     } else if (!ff_guidcmp(mediatype, mediatype_mpeg2_sections) &&
00696                !ff_guidcmp(subtype, mediasubtype_mpeg2_sections)) {
00697         if (ff_guidcmp(formattype, ff_format_none))
00698             av_log(s, AV_LOG_WARNING, "unknown formattype:"FF_PRI_GUID"\n", FF_ARG_GUID(formattype));
00699         avio_skip(pb, size);
00700         return NULL;
00701     }
00702 
00703     av_log(s, AV_LOG_WARNING, "unknown media type, mediatype:"FF_PRI_GUID
00704                               ", subtype:"FF_PRI_GUID", formattype:"FF_PRI_GUID"\n",
00705                               FF_ARG_GUID(mediatype), FF_ARG_GUID(subtype), FF_ARG_GUID(formattype));
00706     avio_skip(pb, size);
00707     return NULL;
00708 }
00709 
00710 enum {
00711     SEEK_TO_DATA = 0,
00712     SEEK_TO_PTS,
00713 };
00714 
00722 static int parse_chunks(AVFormatContext *s, int mode, int64_t seekts, int *len_ptr)
00723 {
00724     WtvContext *wtv = s->priv_data;
00725     AVIOContext *pb = wtv->pb;
00726     while (!url_feof(pb)) {
00727         ff_asf_guid g;
00728         int len, sid, consumed;
00729 
00730         ff_get_guid(pb, &g);
00731         len = avio_rl32(pb);
00732         if (len < 32)
00733             break;
00734         sid = avio_rl32(pb) & 0x7FFF;
00735         avio_skip(pb, 8);
00736         consumed = 32;
00737 
00738         if (!ff_guidcmp(g, ff_stream_guid)) {
00739             if (ff_find_stream_index(s, sid) < 0) {
00740                 ff_asf_guid mediatype, subtype, formattype;
00741                 int size;
00742                 avio_skip(pb, 28);
00743                 ff_get_guid(pb, &mediatype);
00744                 ff_get_guid(pb, &subtype);
00745                 avio_skip(pb, 12);
00746                 ff_get_guid(pb, &formattype);
00747                 size = avio_rl32(pb);
00748                 parse_media_type(s, 0, sid, mediatype, subtype, formattype, size);
00749                 consumed += 92 + size;
00750             }
00751         } else if (!ff_guidcmp(g, stream2_guid)) {
00752             int stream_index = ff_find_stream_index(s, sid);
00753             if (stream_index >= 0 && !((WtvStream*)s->streams[stream_index]->priv_data)->seen_data) {
00754                 ff_asf_guid mediatype, subtype, formattype;
00755                 int size;
00756                 avio_skip(pb, 12);
00757                 ff_get_guid(pb, &mediatype);
00758                 ff_get_guid(pb, &subtype);
00759                 avio_skip(pb, 12);
00760                 ff_get_guid(pb, &formattype);
00761                 size = avio_rl32(pb);
00762                 parse_media_type(s, s->streams[stream_index], sid, mediatype, subtype, formattype, size);
00763                 consumed += 76 + size;
00764             }
00765         } else if (!ff_guidcmp(g, EVENTID_AudioDescriptorSpanningEvent) ||
00766                    !ff_guidcmp(g, EVENTID_CtxADescriptorSpanningEvent) ||
00767                    !ff_guidcmp(g, EVENTID_CSDescriptorSpanningEvent) ||
00768                    !ff_guidcmp(g, EVENTID_StreamIDSpanningEvent) ||
00769                    !ff_guidcmp(g, EVENTID_SubtitleSpanningEvent) ||
00770                    !ff_guidcmp(g, EVENTID_TeletextSpanningEvent)) {
00771             int stream_index = ff_find_stream_index(s, sid);
00772             if (stream_index >= 0) {
00773                 AVStream *st = s->streams[stream_index];
00774                 uint8_t buf[258];
00775                 const uint8_t *pbuf = buf;
00776                 int buf_size;
00777 
00778                 avio_skip(pb, 8);
00779                 consumed += 8;
00780                 if (!ff_guidcmp(g, EVENTID_CtxADescriptorSpanningEvent) ||
00781                     !ff_guidcmp(g, EVENTID_CSDescriptorSpanningEvent)) {
00782                     avio_skip(pb, 6);
00783                     consumed += 6;
00784                 }
00785 
00786                 buf_size = FFMIN(len - consumed, sizeof(buf));
00787                 avio_read(pb, buf, buf_size);
00788                 consumed += buf_size;
00789                 ff_parse_mpeg2_descriptor(s, st, 0, &pbuf, buf + buf_size, 0, 0, 0, 0);
00790             }
00791         } else if (!ff_guidcmp(g, EVENTID_AudioTypeSpanningEvent)) {
00792             int stream_index = ff_find_stream_index(s, sid);
00793             if (stream_index >= 0) {
00794                 AVStream *st = s->streams[stream_index];
00795                 int audio_type;
00796                 avio_skip(pb, 8);
00797                 audio_type = avio_r8(pb);
00798                 if (audio_type == 2)
00799                     st->disposition |= AV_DISPOSITION_HEARING_IMPAIRED;
00800                 else if (audio_type == 3)
00801                     st->disposition |= AV_DISPOSITION_VISUAL_IMPAIRED;
00802                 consumed += 9;
00803             }
00804         } else if (!ff_guidcmp(g, EVENTID_DVBScramblingControlSpanningEvent)) {
00805             int stream_index = ff_find_stream_index(s, sid);
00806             if (stream_index >= 0) {
00807                 avio_skip(pb, 12);
00808                 if (avio_rl32(pb))
00809                     av_log(s, AV_LOG_WARNING, "DVB scrambled stream detected (st:%d), decoding will likely fail\n", stream_index);
00810                 consumed += 16;
00811             }
00812         } else if (!ff_guidcmp(g, EVENTID_LanguageSpanningEvent)) {
00813             int stream_index = ff_find_stream_index(s, sid);
00814             if (stream_index >= 0) {
00815                 AVStream *st = s->streams[stream_index];
00816                 uint8_t language[4];
00817                 avio_skip(pb, 12);
00818                 avio_read(pb, language, 3);
00819                 if (language[0]) {
00820                     language[3] = 0;
00821                     av_dict_set(&st->metadata, "language", language, 0);
00822                     if (!strcmp(language, "nar") || !strcmp(language, "NAR"))
00823                         st->disposition |= AV_DISPOSITION_VISUAL_IMPAIRED;
00824                 }
00825                 consumed += 15;
00826             }
00827         } else if (!ff_guidcmp(g, ff_timestamp_guid)) {
00828             int stream_index = ff_find_stream_index(s, sid);
00829             if (stream_index >= 0) {
00830                 avio_skip(pb, 8);
00831                 wtv->pts = avio_rl64(pb);
00832                 consumed += 16;
00833                 if (wtv->pts == -1)
00834                     wtv->pts = AV_NOPTS_VALUE;
00835                 else {
00836                     wtv->last_valid_pts = wtv->pts;
00837                     if (wtv->epoch == AV_NOPTS_VALUE || wtv->pts < wtv->epoch)
00838                         wtv->epoch = wtv->pts;
00839                 if (mode == SEEK_TO_PTS && wtv->pts >= seekts) {
00840 #define WTV_PAD8(x) (((x) + 7) & ~7)
00841                     avio_skip(pb, WTV_PAD8(len) - consumed);
00842                     return 0;
00843                 }
00844                 }
00845             }
00846         } else if (!ff_guidcmp(g, ff_data_guid)) {
00847             int stream_index = ff_find_stream_index(s, sid);
00848             if (mode == SEEK_TO_DATA && stream_index >= 0 && len > 32) {
00849                 WtvStream *wst = s->streams[stream_index]->priv_data;
00850                 wst->seen_data = 1;
00851                 if (len_ptr) {
00852                     *len_ptr = len;
00853                 }
00854                 return stream_index;
00855             }
00856         } else if (
00857             !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}) ||
00858             !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}) ||
00859             !ff_guidcmp(g, /* DSATTRIB_TRANSPORT_PROPERTIES */ (const ff_asf_guid){0x12,0xF6,0x22,0xB6,0xAD,0x47,0x71,0x46,0xAD,0x6C,0x05,0xA9,0x8E,0x65,0xDE,0x3A}) ||
00860             !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}) ||
00861             !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}) ||
00862             !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}) ||
00863             !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}) ||
00864             !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}) ||
00865             !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}) ||
00866             !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}) ||
00867             !ff_guidcmp(g, (const ff_asf_guid){0x1E,0xBE,0xC3,0xC5,0x43,0x92,0xDC,0x11,0x85,0xE5,0x00,0x12,0x3F,0x6F,0x73,0xB9}) ||
00868             !ff_guidcmp(g, (const ff_asf_guid){0x3B,0x86,0xA2,0xB1,0xEB,0x1E,0xC3,0x44,0x8C,0x88,0x1C,0xA3,0xFF,0xE3,0xE7,0x6A}) ||
00869             !ff_guidcmp(g, (const ff_asf_guid){0x4E,0x7F,0x4C,0x5B,0xC4,0xD0,0x38,0x4B,0xA8,0x3E,0x21,0x7F,0x7B,0xBF,0x52,0xE7}) ||
00870             !ff_guidcmp(g, (const ff_asf_guid){0x63,0x36,0xEB,0xFE,0xA1,0x7E,0xD9,0x11,0x83,0x08,0x00,0x07,0xE9,0x5E,0xAD,0x8D}) ||
00871             !ff_guidcmp(g, (const ff_asf_guid){0x70,0xE9,0xF1,0xF8,0x89,0xA4,0x4C,0x4D,0x83,0x73,0xB8,0x12,0xE0,0xD5,0xF8,0x1E}) ||
00872             !ff_guidcmp(g, (const ff_asf_guid){0x96,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D}) ||
00873             !ff_guidcmp(g, (const ff_asf_guid){0x97,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D}) ||
00874             !ff_guidcmp(g, (const ff_asf_guid){0xA1,0xC3,0xD2,0xC2,0x7E,0x9A,0xDA,0x11,0x8B,0xF7,0x00,0x07,0xE9,0x5E,0xAD,0x8D})) {
00875             //ignore known guids
00876         } else
00877             av_log(s, AV_LOG_WARNING, "unsupported chunk:"FF_PRI_GUID"\n", FF_ARG_GUID(g));
00878 
00879         avio_skip(pb, WTV_PAD8(len) - consumed);
00880     }
00881     return AVERROR_EOF;
00882 }
00883 
00884 /* declare utf16le strings */
00885 #define _ , 0,
00886 static const uint8_t timeline_le16[] =
00887     {'t'_'i'_'m'_'e'_'l'_'i'_'n'_'e', 0};
00888 static const uint8_t table_0_entries_legacy_attrib_le16[] =
00889     {'t'_'a'_'b'_'l'_'e'_'.'_'0'_'.'_'e'_'n'_'t'_'r'_'i'_'e'_'s'_'.'_'l'_'e'_'g'_'a'_'c'_'y'_'_'_'a'_'t'_'t'_'r'_'i'_'b', 0};
00890 static const uint8_t table_0_entries_time_le16[] =
00891     {'t'_'a'_'b'_'l'_'e'_'.'_'0'_'.'_'e'_'n'_'t'_'r'_'i'_'e'_'s'_'.'_'t'_'i'_'m'_'e', 0};
00892 static const uint8_t timeline_table_0_entries_Events_le16[] =
00893     {'t'_'i'_'m'_'e'_'l'_'i'_'n'_'e'_'.'_'t'_'a'_'b'_'l'_'e'_'.'_'0'_'.'_'e'_'n'_'t'_'r'_'i'_'e'_'s'_'.'_'E'_'v'_'e'_'n'_'t'_'s', 0};
00894 #undef _
00895 
00896 static int read_header(AVFormatContext *s, AVFormatParameters *ap)
00897 {
00898     WtvContext *wtv = s->priv_data;
00899     int root_sector, root_size;
00900     uint8_t root[WTV_SECTOR_SIZE];
00901     AVIOContext *pb;
00902     int64_t timeline_pos;
00903     int ret;
00904 
00905     wtv->epoch          =
00906     wtv->pts            =
00907     wtv->last_valid_pts = AV_NOPTS_VALUE;
00908 
00909     /* read root directory sector */
00910     avio_skip(s->pb, 0x30);
00911     root_size = avio_rl32(s->pb);
00912     if (root_size > sizeof(root)) {
00913         av_log(s, AV_LOG_ERROR, "root directory size exceeds sector size\n");
00914         return AVERROR_INVALIDDATA;
00915     }
00916     avio_skip(s->pb, 4);
00917     root_sector = avio_rl32(s->pb);
00918 
00919     avio_seek(s->pb, root_sector << WTV_SECTOR_BITS, SEEK_SET);
00920     root_size = avio_read(s->pb, root, root_size);
00921     if (root_size < 0)
00922         return AVERROR_INVALIDDATA;
00923 
00924     /* parse chunks up until first data chunk */
00925     wtv->pb = wtvfile_open(s, root, root_size, timeline_le16);
00926     if (!wtv->pb) {
00927         av_log(s, AV_LOG_ERROR, "timeline data missing\n");
00928         return AVERROR_INVALIDDATA;
00929     }
00930 
00931     ret = parse_chunks(s, SEEK_TO_DATA, 0, 0);
00932     if (ret < 0)
00933         return ret;
00934     avio_seek(wtv->pb, -32, SEEK_CUR);
00935 
00936     timeline_pos = avio_tell(s->pb); // save before opening another file
00937 
00938     /* read metadata */
00939     pb = wtvfile_open(s, root, root_size, table_0_entries_legacy_attrib_le16);
00940     if (pb) {
00941         parse_legacy_attrib(s, pb);
00942         wtvfile_close(pb);
00943     }
00944 
00945     /* read seek index */
00946     if (s->nb_streams) {
00947         AVStream *st = s->streams[0];
00948         pb = wtvfile_open(s, root, root_size, table_0_entries_time_le16);
00949         if (pb) {
00950             while(1) {
00951                 uint64_t timestamp = avio_rl64(pb);
00952                 uint64_t frame_nb  = avio_rl64(pb);
00953                 if (url_feof(pb))
00954                     break;
00955                 ff_add_index_entry(&wtv->index_entries, &wtv->nb_index_entries, &wtv->index_entries_allocated_size,
00956                                    0, timestamp, frame_nb, 0, AVINDEX_KEYFRAME);
00957             }
00958             wtvfile_close(pb);
00959 
00960             if (wtv->nb_index_entries) {
00961                 pb = wtvfile_open(s, root, root_size, timeline_table_0_entries_Events_le16);
00962                 if (pb) {
00963                     int i;
00964                     while (1) {
00965                         uint64_t frame_nb = avio_rl64(pb);
00966                         uint64_t position = avio_rl64(pb);
00967                         if (url_feof(pb))
00968                             break;
00969                         for (i = wtv->nb_index_entries - 1; i >= 0; i--) {
00970                             AVIndexEntry *e = wtv->index_entries + i;
00971                             if (frame_nb > e->size)
00972                                 break;
00973                             if (position > e->pos)
00974                                 e->pos = position;
00975                         }
00976                     }
00977                     wtvfile_close(pb);
00978                     st->duration = wtv->index_entries[wtv->nb_index_entries - 1].timestamp;
00979                 }
00980             }
00981         }
00982     }
00983 
00984     avio_seek(s->pb, timeline_pos, SEEK_SET);
00985     return 0;
00986 }
00987 
00988 static int read_packet(AVFormatContext *s, AVPacket *pkt)
00989 {
00990     WtvContext *wtv = s->priv_data;
00991     AVIOContext *pb = wtv->pb;
00992     int stream_index, len, ret;
00993 
00994     stream_index = parse_chunks(s, SEEK_TO_DATA, 0, &len);
00995     if (stream_index < 0)
00996         return stream_index;
00997 
00998     ret = av_get_packet(pb, pkt, len - 32);
00999     if (ret < 0)
01000         return ret;
01001     pkt->stream_index = stream_index;
01002     pkt->pts          = wtv->pts;
01003     avio_skip(pb, WTV_PAD8(len) - len);
01004     return 0;
01005 }
01006 
01007 static int read_seek(AVFormatContext *s, int stream_index,
01008                      int64_t ts, int flags)
01009 {
01010     WtvContext *wtv = s->priv_data;
01011     AVIOContext *pb = wtv->pb;
01012     AVStream *st = s->streams[0];
01013     int64_t ts_relative;
01014     int i;
01015 
01016     if ((flags & AVSEEK_FLAG_FRAME) || (flags & AVSEEK_FLAG_BYTE))
01017         return AVERROR(ENOSYS);
01018 
01019     /* timestamp adjustment is required because wtv->pts values are absolute,
01020      * whereas AVIndexEntry->timestamp values are relative to epoch. */
01021     ts_relative = ts;
01022     if (wtv->epoch != AV_NOPTS_VALUE)
01023         ts_relative -= wtv->epoch;
01024 
01025     i = ff_index_search_timestamp(wtv->index_entries, wtv->nb_index_entries, ts_relative, flags);
01026     if (i < 0) {
01027         if (wtv->last_valid_pts == AV_NOPTS_VALUE || ts < wtv->last_valid_pts)
01028             avio_seek(pb, 0, SEEK_SET);
01029         else if (st->duration != AV_NOPTS_VALUE && ts_relative > st->duration && wtv->nb_index_entries)
01030             avio_seek(pb, wtv->index_entries[wtv->nb_index_entries - 1].pos, SEEK_SET);
01031         if (parse_chunks(s, SEEK_TO_PTS, ts, 0) < 0)
01032             return AVERROR(ERANGE);
01033         return 0;
01034     }
01035     wtv->pts = wtv->index_entries[i].timestamp;
01036     if (wtv->epoch != AV_NOPTS_VALUE)
01037         wtv->pts += wtv->epoch;
01038     wtv->last_valid_pts = wtv->pts;
01039     avio_seek(pb, wtv->index_entries[i].pos, SEEK_SET);
01040     return 0;
01041 }
01042 
01043 static int read_close(AVFormatContext *s)
01044 {
01045     WtvContext *wtv = s->priv_data;
01046     wtvfile_close(wtv->pb);
01047     return 0;
01048 }
01049 
01050 AVInputFormat ff_wtv_demuxer = {
01051     .name           = "wtv",
01052     .long_name      = NULL_IF_CONFIG_SMALL("Windows Television (WTV)"),
01053     .priv_data_size = sizeof(WtvContext),
01054     .read_probe     = read_probe,
01055     .read_header    = read_header,
01056     .read_packet    = read_packet,
01057     .read_seek      = read_seek,
01058     .read_close     = read_close,
01059     .flags          = AVFMT_SHOW_IDS,
01060 };