Libav 0.7.1
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00001 /* 00002 * FLV demuxer 00003 * Copyright (c) 2003 The Libav Project 00004 * 00005 * This demuxer will generate a 1 byte extradata for VP6F content. 00006 * It is composed of: 00007 * - upper 4bits: difference between encoded width and visible width 00008 * - lower 4bits: difference between encoded height and visible height 00009 * 00010 * This file is part of Libav. 00011 * 00012 * Libav is free software; you can redistribute it and/or 00013 * modify it under the terms of the GNU Lesser General Public 00014 * License as published by the Free Software Foundation; either 00015 * version 2.1 of the License, or (at your option) any later version. 00016 * 00017 * Libav is distributed in the hope that it will be useful, 00018 * but WITHOUT ANY WARRANTY; without even the implied warranty of 00019 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 00020 * Lesser General Public License for more details. 00021 * 00022 * You should have received a copy of the GNU Lesser General Public 00023 * License along with Libav; if not, write to the Free Software 00024 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 00025 */ 00026 00027 #include "libavutil/avstring.h" 00028 #include "libavutil/dict.h" 00029 #include "libavcodec/bytestream.h" 00030 #include "libavcodec/mpeg4audio.h" 00031 #include "avformat.h" 00032 #include "avio_internal.h" 00033 #include "flv.h" 00034 00035 #define KEYFRAMES_TAG "keyframes" 00036 #define KEYFRAMES_TIMESTAMP_TAG "times" 00037 #define KEYFRAMES_BYTEOFFSET_TAG "filepositions" 00038 00039 typedef struct { 00040 int wrong_dts; 00041 } FLVContext; 00042 00043 static int flv_probe(AVProbeData *p) 00044 { 00045 const uint8_t *d; 00046 00047 d = p->buf; 00048 if (d[0] == 'F' && d[1] == 'L' && d[2] == 'V' && d[3] < 5 && d[5]==0 && AV_RB32(d+5)>8) { 00049 return AVPROBE_SCORE_MAX; 00050 } 00051 return 0; 00052 } 00053 00054 static void flv_set_audio_codec(AVFormatContext *s, AVStream *astream, int flv_codecid) { 00055 AVCodecContext *acodec = astream->codec; 00056 switch(flv_codecid) { 00057 //no distinction between S16 and S8 PCM codec flags 00058 case FLV_CODECID_PCM: 00059 acodec->codec_id = acodec->bits_per_coded_sample == 8 ? CODEC_ID_PCM_U8 : 00060 #if HAVE_BIGENDIAN 00061 CODEC_ID_PCM_S16BE; 00062 #else 00063 CODEC_ID_PCM_S16LE; 00064 #endif 00065 break; 00066 case FLV_CODECID_PCM_LE: 00067 acodec->codec_id = acodec->bits_per_coded_sample == 8 ? CODEC_ID_PCM_U8 : CODEC_ID_PCM_S16LE; break; 00068 case FLV_CODECID_AAC : acodec->codec_id = CODEC_ID_AAC; break; 00069 case FLV_CODECID_ADPCM: acodec->codec_id = CODEC_ID_ADPCM_SWF; break; 00070 case FLV_CODECID_SPEEX: 00071 acodec->codec_id = CODEC_ID_SPEEX; 00072 acodec->sample_rate = 16000; 00073 break; 00074 case FLV_CODECID_MP3 : acodec->codec_id = CODEC_ID_MP3 ; astream->need_parsing = AVSTREAM_PARSE_FULL; break; 00075 case FLV_CODECID_NELLYMOSER_8KHZ_MONO: 00076 acodec->sample_rate = 8000; //in case metadata does not otherwise declare samplerate 00077 acodec->codec_id = CODEC_ID_NELLYMOSER; 00078 break; 00079 case FLV_CODECID_NELLYMOSER_16KHZ_MONO: 00080 acodec->sample_rate = 16000; 00081 acodec->codec_id = CODEC_ID_NELLYMOSER; 00082 break; 00083 case FLV_CODECID_NELLYMOSER: 00084 acodec->codec_id = CODEC_ID_NELLYMOSER; 00085 break; 00086 default: 00087 av_log(s, AV_LOG_INFO, "Unsupported audio codec (%x)\n", flv_codecid >> FLV_AUDIO_CODECID_OFFSET); 00088 acodec->codec_tag = flv_codecid >> FLV_AUDIO_CODECID_OFFSET; 00089 } 00090 } 00091 00092 static int flv_set_video_codec(AVFormatContext *s, AVStream *vstream, int flv_codecid) { 00093 AVCodecContext *vcodec = vstream->codec; 00094 switch(flv_codecid) { 00095 case FLV_CODECID_H263 : vcodec->codec_id = CODEC_ID_FLV1 ; break; 00096 case FLV_CODECID_SCREEN: vcodec->codec_id = CODEC_ID_FLASHSV; break; 00097 case FLV_CODECID_SCREEN2: vcodec->codec_id = CODEC_ID_FLASHSV2; break; 00098 case FLV_CODECID_VP6 : vcodec->codec_id = CODEC_ID_VP6F ; 00099 case FLV_CODECID_VP6A : 00100 if(flv_codecid == FLV_CODECID_VP6A) 00101 vcodec->codec_id = CODEC_ID_VP6A; 00102 if(vcodec->extradata_size != 1) { 00103 vcodec->extradata_size = 1; 00104 vcodec->extradata = av_malloc(1); 00105 } 00106 vcodec->extradata[0] = avio_r8(s->pb); 00107 return 1; // 1 byte body size adjustment for flv_read_packet() 00108 case FLV_CODECID_H264: 00109 vcodec->codec_id = CODEC_ID_H264; 00110 return 3; // not 4, reading packet type will consume one byte 00111 default: 00112 av_log(s, AV_LOG_INFO, "Unsupported video codec (%x)\n", flv_codecid); 00113 vcodec->codec_tag = flv_codecid; 00114 } 00115 00116 return 0; 00117 } 00118 00119 static int amf_get_string(AVIOContext *ioc, char *buffer, int buffsize) { 00120 int length = avio_rb16(ioc); 00121 if(length >= buffsize) { 00122 avio_skip(ioc, length); 00123 return -1; 00124 } 00125 00126 avio_read(ioc, buffer, length); 00127 00128 buffer[length] = '\0'; 00129 00130 return length; 00131 } 00132 00133 static int parse_keyframes_index(AVFormatContext *s, AVIOContext *ioc, AVStream *vstream, int64_t max_pos) { 00134 unsigned int arraylen = 0, timeslen = 0, fileposlen = 0, i; 00135 double num_val; 00136 char str_val[256]; 00137 int64_t *times = NULL; 00138 int64_t *filepositions = NULL; 00139 int ret = AVERROR(ENOSYS); 00140 int64_t initial_pos = avio_tell(ioc); 00141 00142 while (avio_tell(ioc) < max_pos - 2 && amf_get_string(ioc, str_val, sizeof(str_val)) > 0) { 00143 int64_t* current_array; 00144 00145 // Expect array object in context 00146 if (avio_r8(ioc) != AMF_DATA_TYPE_ARRAY) 00147 break; 00148 00149 arraylen = avio_rb32(ioc); 00150 if (arraylen >> 28) 00151 break; 00152 00153 /* 00154 * Expect only 'times' or 'filepositions' sub-arrays in other case refuse to use such metadata 00155 * for indexing 00156 */ 00157 if (!strcmp(KEYFRAMES_TIMESTAMP_TAG, str_val) && !times) { 00158 if (!(times = av_mallocz(sizeof(*times) * arraylen))) { 00159 ret = AVERROR(ENOMEM); 00160 goto finish; 00161 } 00162 timeslen = arraylen; 00163 current_array = times; 00164 } else if (!strcmp(KEYFRAMES_BYTEOFFSET_TAG, str_val) && !filepositions) { 00165 if (!(filepositions = av_mallocz(sizeof(*filepositions) * arraylen))) { 00166 ret = AVERROR(ENOMEM); 00167 goto finish; 00168 } 00169 fileposlen = arraylen; 00170 current_array = filepositions; 00171 } else // unexpected metatag inside keyframes, will not use such metadata for indexing 00172 break; 00173 00174 for (i = 0; i < arraylen && avio_tell(ioc) < max_pos - 1; i++) { 00175 if (avio_r8(ioc) != AMF_DATA_TYPE_NUMBER) 00176 goto finish; 00177 num_val = av_int2dbl(avio_rb64(ioc)); 00178 current_array[i] = num_val; 00179 } 00180 if (times && filepositions) { 00181 // All done, exiting at a position allowing amf_parse_object 00182 // to finish parsing the object 00183 ret = 0; 00184 break; 00185 } 00186 } 00187 00188 if (timeslen == fileposlen) 00189 for(i = 0; i < arraylen; i++) 00190 av_add_index_entry(vstream, filepositions[i], times[i]*1000, 0, 0, AVINDEX_KEYFRAME); 00191 else 00192 av_log(s, AV_LOG_WARNING, "Invalid keyframes object, skipping.\n"); 00193 00194 finish: 00195 av_freep(×); 00196 av_freep(&filepositions); 00197 // If we got unexpected data, but successfully reset back to 00198 // the start pos, the caller can continue parsing 00199 if (ret < 0 && avio_seek(ioc, initial_pos, SEEK_SET) > 0) 00200 return 0; 00201 return ret; 00202 } 00203 00204 static int amf_parse_object(AVFormatContext *s, AVStream *astream, AVStream *vstream, const char *key, int64_t max_pos, int depth) { 00205 AVCodecContext *acodec, *vcodec; 00206 AVIOContext *ioc; 00207 AMFDataType amf_type; 00208 char str_val[256]; 00209 double num_val; 00210 00211 num_val = 0; 00212 ioc = s->pb; 00213 00214 amf_type = avio_r8(ioc); 00215 00216 switch(amf_type) { 00217 case AMF_DATA_TYPE_NUMBER: 00218 num_val = av_int2dbl(avio_rb64(ioc)); break; 00219 case AMF_DATA_TYPE_BOOL: 00220 num_val = avio_r8(ioc); break; 00221 case AMF_DATA_TYPE_STRING: 00222 if(amf_get_string(ioc, str_val, sizeof(str_val)) < 0) 00223 return -1; 00224 break; 00225 case AMF_DATA_TYPE_OBJECT: { 00226 unsigned int keylen; 00227 00228 if (key && !strcmp(KEYFRAMES_TAG, key) && depth == 1) 00229 if (parse_keyframes_index(s, ioc, vstream, max_pos) < 0) 00230 return -1; 00231 00232 while(avio_tell(ioc) < max_pos - 2 && (keylen = avio_rb16(ioc))) { 00233 avio_skip(ioc, keylen); //skip key string 00234 if(amf_parse_object(s, NULL, NULL, NULL, max_pos, depth + 1) < 0) 00235 return -1; //if we couldn't skip, bomb out. 00236 } 00237 if(avio_r8(ioc) != AMF_END_OF_OBJECT) 00238 return -1; 00239 } 00240 break; 00241 case AMF_DATA_TYPE_NULL: 00242 case AMF_DATA_TYPE_UNDEFINED: 00243 case AMF_DATA_TYPE_UNSUPPORTED: 00244 break; //these take up no additional space 00245 case AMF_DATA_TYPE_MIXEDARRAY: 00246 avio_skip(ioc, 4); //skip 32-bit max array index 00247 while(avio_tell(ioc) < max_pos - 2 && amf_get_string(ioc, str_val, sizeof(str_val)) > 0) { 00248 //this is the only case in which we would want a nested parse to not skip over the object 00249 if(amf_parse_object(s, astream, vstream, str_val, max_pos, depth + 1) < 0) 00250 return -1; 00251 } 00252 if(avio_r8(ioc) != AMF_END_OF_OBJECT) 00253 return -1; 00254 break; 00255 case AMF_DATA_TYPE_ARRAY: { 00256 unsigned int arraylen, i; 00257 00258 arraylen = avio_rb32(ioc); 00259 for(i = 0; i < arraylen && avio_tell(ioc) < max_pos - 1; i++) { 00260 if(amf_parse_object(s, NULL, NULL, NULL, max_pos, depth + 1) < 0) 00261 return -1; //if we couldn't skip, bomb out. 00262 } 00263 } 00264 break; 00265 case AMF_DATA_TYPE_DATE: 00266 avio_skip(ioc, 8 + 2); //timestamp (double) and UTC offset (int16) 00267 break; 00268 default: //unsupported type, we couldn't skip 00269 return -1; 00270 } 00271 00272 if(depth == 1 && key) { //only look for metadata values when we are not nested and key != NULL 00273 acodec = astream ? astream->codec : NULL; 00274 vcodec = vstream ? vstream->codec : NULL; 00275 00276 if(amf_type == AMF_DATA_TYPE_BOOL) { 00277 av_strlcpy(str_val, num_val > 0 ? "true" : "false", sizeof(str_val)); 00278 av_dict_set(&s->metadata, key, str_val, 0); 00279 } else if(amf_type == AMF_DATA_TYPE_NUMBER) { 00280 snprintf(str_val, sizeof(str_val), "%.f", num_val); 00281 av_dict_set(&s->metadata, key, str_val, 0); 00282 if(!strcmp(key, "duration")) s->duration = num_val * AV_TIME_BASE; 00283 else if(!strcmp(key, "videodatarate") && vcodec && 0 <= (int)(num_val * 1024.0)) 00284 vcodec->bit_rate = num_val * 1024.0; 00285 else if(!strcmp(key, "audiodatarate") && acodec && 0 <= (int)(num_val * 1024.0)) 00286 acodec->bit_rate = num_val * 1024.0; 00287 } else if (amf_type == AMF_DATA_TYPE_STRING) 00288 av_dict_set(&s->metadata, key, str_val, 0); 00289 } 00290 00291 return 0; 00292 } 00293 00294 static int flv_read_metabody(AVFormatContext *s, int64_t next_pos) { 00295 AMFDataType type; 00296 AVStream *stream, *astream, *vstream; 00297 AVIOContext *ioc; 00298 int i; 00299 char buffer[11]; //only needs to hold the string "onMetaData". Anything longer is something we don't want. 00300 00301 astream = NULL; 00302 vstream = NULL; 00303 ioc = s->pb; 00304 00305 //first object needs to be "onMetaData" string 00306 type = avio_r8(ioc); 00307 if(type != AMF_DATA_TYPE_STRING || amf_get_string(ioc, buffer, sizeof(buffer)) < 0 || strcmp(buffer, "onMetaData")) 00308 return -1; 00309 00310 //find the streams now so that amf_parse_object doesn't need to do the lookup every time it is called. 00311 for(i = 0; i < s->nb_streams; i++) { 00312 stream = s->streams[i]; 00313 if (stream->codec->codec_type == AVMEDIA_TYPE_AUDIO) astream = stream; 00314 else if(stream->codec->codec_type == AVMEDIA_TYPE_VIDEO) vstream = stream; 00315 } 00316 00317 //parse the second object (we want a mixed array) 00318 if(amf_parse_object(s, astream, vstream, buffer, next_pos, 0) < 0) 00319 return -1; 00320 00321 return 0; 00322 } 00323 00324 static AVStream *create_stream(AVFormatContext *s, int is_audio){ 00325 AVStream *st = av_new_stream(s, is_audio); 00326 if (!st) 00327 return NULL; 00328 st->codec->codec_type = is_audio ? AVMEDIA_TYPE_AUDIO : AVMEDIA_TYPE_VIDEO; 00329 av_set_pts_info(st, 32, 1, 1000); /* 32 bit pts in ms */ 00330 return st; 00331 } 00332 00333 static int flv_read_header(AVFormatContext *s, 00334 AVFormatParameters *ap) 00335 { 00336 int offset, flags; 00337 00338 avio_skip(s->pb, 4); 00339 flags = avio_r8(s->pb); 00340 /* old flvtool cleared this field */ 00341 /* FIXME: better fix needed */ 00342 if (!flags) { 00343 flags = FLV_HEADER_FLAG_HASVIDEO | FLV_HEADER_FLAG_HASAUDIO; 00344 av_log(s, AV_LOG_WARNING, "Broken FLV file, which says no streams present, this might fail\n"); 00345 } 00346 00347 if((flags & (FLV_HEADER_FLAG_HASVIDEO|FLV_HEADER_FLAG_HASAUDIO)) 00348 != (FLV_HEADER_FLAG_HASVIDEO|FLV_HEADER_FLAG_HASAUDIO)) 00349 s->ctx_flags |= AVFMTCTX_NOHEADER; 00350 00351 if(flags & FLV_HEADER_FLAG_HASVIDEO){ 00352 if(!create_stream(s, 0)) 00353 return AVERROR(ENOMEM); 00354 } 00355 if(flags & FLV_HEADER_FLAG_HASAUDIO){ 00356 if(!create_stream(s, 1)) 00357 return AVERROR(ENOMEM); 00358 } 00359 00360 offset = avio_rb32(s->pb); 00361 avio_seek(s->pb, offset, SEEK_SET); 00362 avio_skip(s->pb, 4); 00363 00364 s->start_time = 0; 00365 00366 return 0; 00367 } 00368 00369 static int flv_get_extradata(AVFormatContext *s, AVStream *st, int size) 00370 { 00371 av_free(st->codec->extradata); 00372 st->codec->extradata = av_mallocz(size + FF_INPUT_BUFFER_PADDING_SIZE); 00373 if (!st->codec->extradata) 00374 return AVERROR(ENOMEM); 00375 st->codec->extradata_size = size; 00376 avio_read(s->pb, st->codec->extradata, st->codec->extradata_size); 00377 return 0; 00378 } 00379 00380 static int flv_read_packet(AVFormatContext *s, AVPacket *pkt) 00381 { 00382 FLVContext *flv = s->priv_data; 00383 int ret, i, type, size, flags, is_audio; 00384 int64_t next, pos; 00385 int64_t dts, pts = AV_NOPTS_VALUE; 00386 AVStream *st = NULL; 00387 00388 for(;;avio_skip(s->pb, 4)){ /* pkt size is repeated at end. skip it */ 00389 pos = avio_tell(s->pb); 00390 type = avio_r8(s->pb); 00391 size = avio_rb24(s->pb); 00392 dts = avio_rb24(s->pb); 00393 dts |= avio_r8(s->pb) << 24; 00394 av_dlog(s, "type:%d, size:%d, dts:%"PRId64"\n", type, size, dts); 00395 if (s->pb->eof_reached) 00396 return AVERROR_EOF; 00397 avio_skip(s->pb, 3); /* stream id, always 0 */ 00398 flags = 0; 00399 00400 if(size == 0) 00401 continue; 00402 00403 next= size + avio_tell(s->pb); 00404 00405 if (type == FLV_TAG_TYPE_AUDIO) { 00406 is_audio=1; 00407 flags = avio_r8(s->pb); 00408 size--; 00409 } else if (type == FLV_TAG_TYPE_VIDEO) { 00410 is_audio=0; 00411 flags = avio_r8(s->pb); 00412 size--; 00413 if ((flags & 0xf0) == 0x50) /* video info / command frame */ 00414 goto skip; 00415 } else { 00416 if (type == FLV_TAG_TYPE_META && size > 13+1+4) 00417 flv_read_metabody(s, next); 00418 else /* skip packet */ 00419 av_log(s, AV_LOG_DEBUG, "skipping flv packet: type %d, size %d, flags %d\n", type, size, flags); 00420 skip: 00421 avio_seek(s->pb, next, SEEK_SET); 00422 continue; 00423 } 00424 00425 /* skip empty data packets */ 00426 if (!size) 00427 continue; 00428 00429 /* now find stream */ 00430 for(i=0;i<s->nb_streams;i++) { 00431 st = s->streams[i]; 00432 if (st->id == is_audio) 00433 break; 00434 } 00435 if(i == s->nb_streams){ 00436 av_log(s, AV_LOG_ERROR, "invalid stream\n"); 00437 st= create_stream(s, is_audio); 00438 s->ctx_flags &= ~AVFMTCTX_NOHEADER; 00439 } 00440 av_dlog(s, "%d %X %d \n", is_audio, flags, st->discard); 00441 if( (st->discard >= AVDISCARD_NONKEY && !((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY || is_audio)) 00442 ||(st->discard >= AVDISCARD_BIDIR && ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_DISP_INTER && !is_audio)) 00443 || st->discard >= AVDISCARD_ALL 00444 ){ 00445 avio_seek(s->pb, next, SEEK_SET); 00446 continue; 00447 } 00448 if ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY) 00449 av_add_index_entry(st, pos, dts, size, 0, AVINDEX_KEYFRAME); 00450 break; 00451 } 00452 00453 // if not streamed and no duration from metadata then seek to end to find the duration from the timestamps 00454 if(s->pb->seekable && (!s->duration || s->duration==AV_NOPTS_VALUE)){ 00455 int size; 00456 const int64_t pos= avio_tell(s->pb); 00457 const int64_t fsize= avio_size(s->pb); 00458 avio_seek(s->pb, fsize-4, SEEK_SET); 00459 size= avio_rb32(s->pb); 00460 avio_seek(s->pb, fsize-3-size, SEEK_SET); 00461 if(size == avio_rb24(s->pb) + 11){ 00462 uint32_t ts = avio_rb24(s->pb); 00463 ts |= avio_r8(s->pb) << 24; 00464 s->duration = ts * (int64_t)AV_TIME_BASE / 1000; 00465 } 00466 avio_seek(s->pb, pos, SEEK_SET); 00467 } 00468 00469 if(is_audio){ 00470 if(!st->codec->channels || !st->codec->sample_rate || !st->codec->bits_per_coded_sample) { 00471 st->codec->channels = (flags & FLV_AUDIO_CHANNEL_MASK) == FLV_STEREO ? 2 : 1; 00472 st->codec->sample_rate = (44100 << ((flags & FLV_AUDIO_SAMPLERATE_MASK) >> FLV_AUDIO_SAMPLERATE_OFFSET) >> 3); 00473 st->codec->bits_per_coded_sample = (flags & FLV_AUDIO_SAMPLESIZE_MASK) ? 16 : 8; 00474 } 00475 if(!st->codec->codec_id){ 00476 flv_set_audio_codec(s, st, flags & FLV_AUDIO_CODECID_MASK); 00477 } 00478 }else{ 00479 size -= flv_set_video_codec(s, st, flags & FLV_VIDEO_CODECID_MASK); 00480 } 00481 00482 if (st->codec->codec_id == CODEC_ID_AAC || 00483 st->codec->codec_id == CODEC_ID_H264) { 00484 int type = avio_r8(s->pb); 00485 size--; 00486 if (st->codec->codec_id == CODEC_ID_H264) { 00487 int32_t cts = (avio_rb24(s->pb)+0xff800000)^0xff800000; // sign extension 00488 pts = dts + cts; 00489 if (cts < 0) { // dts are wrong 00490 flv->wrong_dts = 1; 00491 av_log(s, AV_LOG_WARNING, "negative cts, previous timestamps might be wrong\n"); 00492 } 00493 if (flv->wrong_dts) 00494 dts = AV_NOPTS_VALUE; 00495 } 00496 if (type == 0) { 00497 if ((ret = flv_get_extradata(s, st, size)) < 0) 00498 return ret; 00499 if (st->codec->codec_id == CODEC_ID_AAC) { 00500 MPEG4AudioConfig cfg; 00501 ff_mpeg4audio_get_config(&cfg, st->codec->extradata, 00502 st->codec->extradata_size); 00503 st->codec->channels = cfg.channels; 00504 if (cfg.ext_sample_rate) 00505 st->codec->sample_rate = cfg.ext_sample_rate; 00506 else 00507 st->codec->sample_rate = cfg.sample_rate; 00508 av_dlog(s, "mp4a config channels %d sample rate %d\n", 00509 st->codec->channels, st->codec->sample_rate); 00510 } 00511 00512 ret = AVERROR(EAGAIN); 00513 goto leave; 00514 } 00515 } 00516 00517 /* skip empty data packets */ 00518 if (!size) { 00519 ret = AVERROR(EAGAIN); 00520 goto leave; 00521 } 00522 00523 ret= av_get_packet(s->pb, pkt, size); 00524 if (ret < 0) { 00525 return AVERROR(EIO); 00526 } 00527 /* note: we need to modify the packet size here to handle the last 00528 packet */ 00529 pkt->size = ret; 00530 pkt->dts = dts; 00531 pkt->pts = pts == AV_NOPTS_VALUE ? dts : pts; 00532 pkt->stream_index = st->index; 00533 00534 if (is_audio || ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY)) 00535 pkt->flags |= AV_PKT_FLAG_KEY; 00536 00537 leave: 00538 avio_skip(s->pb, 4); 00539 return ret; 00540 } 00541 00542 static int flv_read_seek(AVFormatContext *s, int stream_index, 00543 int64_t ts, int flags) 00544 { 00545 return avio_seek_time(s->pb, stream_index, ts, flags); 00546 } 00547 00548 #if 0 /* don't know enough to implement this */ 00549 static int flv_read_seek2(AVFormatContext *s, int stream_index, 00550 int64_t min_ts, int64_t ts, int64_t max_ts, int flags) 00551 { 00552 int ret = AVERROR(ENOSYS); 00553 00554 if (ts - min_ts > (uint64_t)(max_ts - ts)) flags |= AVSEEK_FLAG_BACKWARD; 00555 00556 if (!s->pb->seekable) { 00557 if (stream_index < 0) { 00558 stream_index = av_find_default_stream_index(s); 00559 if (stream_index < 0) 00560 return -1; 00561 00562 /* timestamp for default must be expressed in AV_TIME_BASE units */ 00563 ts = av_rescale_rnd(ts, 1000, AV_TIME_BASE, 00564 flags & AVSEEK_FLAG_BACKWARD ? AV_ROUND_DOWN : AV_ROUND_UP); 00565 } 00566 ret = avio_seek_time(s->pb, stream_index, ts, flags); 00567 } 00568 00569 if (ret == AVERROR(ENOSYS)) 00570 ret = av_seek_frame(s, stream_index, ts, flags); 00571 return ret; 00572 } 00573 #endif 00574 00575 AVInputFormat ff_flv_demuxer = { 00576 "flv", 00577 NULL_IF_CONFIG_SMALL("FLV format"), 00578 sizeof(FLVContext), 00579 flv_probe, 00580 flv_read_header, 00581 flv_read_packet, 00582 .read_seek = flv_read_seek, 00583 #if 0 00584 .read_seek2 = flv_read_seek2, 00585 #endif 00586 .extensions = "flv", 00587 .value = CODEC_ID_FLV1, 00588 };