3 * Copyright (c) 2003 The Libav Project
5 * This demuxer will generate a 1 byte extradata for VP6F content.
7 * - upper 4bits: difference between encoded width and visible width
8 * - lower 4bits: difference between encoded height and visible height
10 * This file is part of Libav.
12 * Libav is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU Lesser General Public
14 * License as published by the Free Software Foundation; either
15 * version 2.1 of the License, or (at your option) any later version.
17 * Libav is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
20 * Lesser General Public License for more details.
22 * You should have received a copy of the GNU Lesser General Public
23 * License along with Libav; if not, write to the Free Software
24 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
27 #include "libavutil/avstring.h"
28 #include "libavutil/dict.h"
29 #include "libavutil/intfloat_readwrite.h"
30 #include "libavutil/mathematics.h"
31 #include "libavcodec/bytestream.h"
32 #include "libavcodec/mpeg4audio.h"
34 #include "avio_internal.h"
37 #define KEYFRAMES_TAG "keyframes"
38 #define KEYFRAMES_TIMESTAMP_TAG "times"
39 #define KEYFRAMES_BYTEOFFSET_TAG "filepositions"
42 int wrong_dts; ///< wrong dts due to negative cts
45 static int flv_probe(AVProbeData *p)
50 if (d[0] == 'F' && d[1] == 'L' && d[2] == 'V' && d[3] < 5 && d[5]==0 && AV_RB32(d+5)>8) {
51 return AVPROBE_SCORE_MAX;
56 static void flv_set_audio_codec(AVFormatContext *s, AVStream *astream, int flv_codecid) {
57 AVCodecContext *acodec = astream->codec;
59 //no distinction between S16 and S8 PCM codec flags
61 acodec->codec_id = acodec->bits_per_coded_sample == 8 ? CODEC_ID_PCM_U8 :
68 case FLV_CODECID_PCM_LE:
69 acodec->codec_id = acodec->bits_per_coded_sample == 8 ? CODEC_ID_PCM_U8 : CODEC_ID_PCM_S16LE; break;
70 case FLV_CODECID_AAC : acodec->codec_id = CODEC_ID_AAC; break;
71 case FLV_CODECID_ADPCM: acodec->codec_id = CODEC_ID_ADPCM_SWF; break;
72 case FLV_CODECID_SPEEX:
73 acodec->codec_id = CODEC_ID_SPEEX;
74 acodec->sample_rate = 16000;
76 case FLV_CODECID_MP3 : acodec->codec_id = CODEC_ID_MP3 ; astream->need_parsing = AVSTREAM_PARSE_FULL; break;
77 case FLV_CODECID_NELLYMOSER_8KHZ_MONO:
78 acodec->sample_rate = 8000; //in case metadata does not otherwise declare samplerate
79 acodec->codec_id = CODEC_ID_NELLYMOSER;
81 case FLV_CODECID_NELLYMOSER_16KHZ_MONO:
82 acodec->sample_rate = 16000;
83 acodec->codec_id = CODEC_ID_NELLYMOSER;
85 case FLV_CODECID_NELLYMOSER:
86 acodec->codec_id = CODEC_ID_NELLYMOSER;
89 av_log(s, AV_LOG_INFO, "Unsupported audio codec (%x)\n", flv_codecid >> FLV_AUDIO_CODECID_OFFSET);
90 acodec->codec_tag = flv_codecid >> FLV_AUDIO_CODECID_OFFSET;
94 static int flv_set_video_codec(AVFormatContext *s, AVStream *vstream, int flv_codecid) {
95 AVCodecContext *vcodec = vstream->codec;
97 case FLV_CODECID_H263 : vcodec->codec_id = CODEC_ID_FLV1 ; break;
98 case FLV_CODECID_SCREEN: vcodec->codec_id = CODEC_ID_FLASHSV; break;
99 case FLV_CODECID_SCREEN2: vcodec->codec_id = CODEC_ID_FLASHSV2; break;
100 case FLV_CODECID_VP6 : vcodec->codec_id = CODEC_ID_VP6F ;
101 case FLV_CODECID_VP6A :
102 if(flv_codecid == FLV_CODECID_VP6A)
103 vcodec->codec_id = CODEC_ID_VP6A;
104 if(vcodec->extradata_size != 1) {
105 vcodec->extradata_size = 1;
106 vcodec->extradata = av_malloc(1);
108 vcodec->extradata[0] = avio_r8(s->pb);
109 return 1; // 1 byte body size adjustment for flv_read_packet()
110 case FLV_CODECID_H264:
111 vcodec->codec_id = CODEC_ID_H264;
112 return 3; // not 4, reading packet type will consume one byte
114 av_log(s, AV_LOG_INFO, "Unsupported video codec (%x)\n", flv_codecid);
115 vcodec->codec_tag = flv_codecid;
121 static int amf_get_string(AVIOContext *ioc, char *buffer, int buffsize) {
122 int length = avio_rb16(ioc);
123 if(length >= buffsize) {
124 avio_skip(ioc, length);
128 avio_read(ioc, buffer, length);
130 buffer[length] = '\0';
135 static int parse_keyframes_index(AVFormatContext *s, AVIOContext *ioc, AVStream *vstream, int64_t max_pos) {
136 unsigned int arraylen = 0, timeslen = 0, fileposlen = 0, i;
139 int64_t *times = NULL;
140 int64_t *filepositions = NULL;
141 int ret = AVERROR(ENOSYS);
142 int64_t initial_pos = avio_tell(ioc);
144 while (avio_tell(ioc) < max_pos - 2 && amf_get_string(ioc, str_val, sizeof(str_val)) > 0) {
145 int64_t* current_array;
147 // Expect array object in context
148 if (avio_r8(ioc) != AMF_DATA_TYPE_ARRAY)
151 arraylen = avio_rb32(ioc);
153 * Expect only 'times' or 'filepositions' sub-arrays in other case refuse to use such metadata
156 if (!strcmp(KEYFRAMES_TIMESTAMP_TAG, str_val) && !times) {
157 if (!(times = av_mallocz(sizeof(*times) * arraylen))) {
158 ret = AVERROR(ENOMEM);
162 current_array = times;
163 } else if (!strcmp(KEYFRAMES_BYTEOFFSET_TAG, str_val) && !filepositions) {
164 if (!(filepositions = av_mallocz(sizeof(*filepositions) * arraylen))) {
165 ret = AVERROR(ENOMEM);
168 fileposlen = arraylen;
169 current_array = filepositions;
170 } else // unexpected metatag inside keyframes, will not use such metadata for indexing
173 for (i = 0; i < arraylen && avio_tell(ioc) < max_pos - 1; i++) {
174 if (avio_r8(ioc) != AMF_DATA_TYPE_NUMBER)
176 num_val = av_int2dbl(avio_rb64(ioc));
177 current_array[i] = num_val;
179 if (times && filepositions) {
180 // All done, exiting at a position allowing amf_parse_object
181 // to finish parsing the object
187 if (timeslen == fileposlen)
188 for(i = 0; i < arraylen; i++)
189 av_add_index_entry(vstream, filepositions[i], times[i]*1000, 0, 0, AVINDEX_KEYFRAME);
191 av_log(s, AV_LOG_WARNING, "Invalid keyframes object, skipping.\n");
195 av_freep(&filepositions);
196 // If we got unexpected data, but successfully reset back to
197 // the start pos, the caller can continue parsing
198 if (ret < 0 && avio_seek(ioc, initial_pos, SEEK_SET) > 0)
203 static int amf_parse_object(AVFormatContext *s, AVStream *astream, AVStream *vstream, const char *key, int64_t max_pos, int depth) {
204 AVCodecContext *acodec, *vcodec;
206 AMFDataType amf_type;
213 amf_type = avio_r8(ioc);
216 case AMF_DATA_TYPE_NUMBER:
217 num_val = av_int2dbl(avio_rb64(ioc)); break;
218 case AMF_DATA_TYPE_BOOL:
219 num_val = avio_r8(ioc); break;
220 case AMF_DATA_TYPE_STRING:
221 if(amf_get_string(ioc, str_val, sizeof(str_val)) < 0)
224 case AMF_DATA_TYPE_OBJECT: {
227 if (key && !strcmp(KEYFRAMES_TAG, key) && depth == 1)
228 if (parse_keyframes_index(s, ioc, vstream, max_pos) < 0)
231 while(avio_tell(ioc) < max_pos - 2 && (keylen = avio_rb16(ioc))) {
232 avio_skip(ioc, keylen); //skip key string
233 if(amf_parse_object(s, NULL, NULL, NULL, max_pos, depth + 1) < 0)
234 return -1; //if we couldn't skip, bomb out.
236 if(avio_r8(ioc) != AMF_END_OF_OBJECT)
240 case AMF_DATA_TYPE_NULL:
241 case AMF_DATA_TYPE_UNDEFINED:
242 case AMF_DATA_TYPE_UNSUPPORTED:
243 break; //these take up no additional space
244 case AMF_DATA_TYPE_MIXEDARRAY:
245 avio_skip(ioc, 4); //skip 32-bit max array index
246 while(avio_tell(ioc) < max_pos - 2 && amf_get_string(ioc, str_val, sizeof(str_val)) > 0) {
247 //this is the only case in which we would want a nested parse to not skip over the object
248 if(amf_parse_object(s, astream, vstream, str_val, max_pos, depth + 1) < 0)
251 if(avio_r8(ioc) != AMF_END_OF_OBJECT)
254 case AMF_DATA_TYPE_ARRAY: {
255 unsigned int arraylen, i;
257 arraylen = avio_rb32(ioc);
258 for(i = 0; i < arraylen && avio_tell(ioc) < max_pos - 1; i++) {
259 if(amf_parse_object(s, NULL, NULL, NULL, max_pos, depth + 1) < 0)
260 return -1; //if we couldn't skip, bomb out.
264 case AMF_DATA_TYPE_DATE:
265 avio_skip(ioc, 8 + 2); //timestamp (double) and UTC offset (int16)
267 default: //unsupported type, we couldn't skip
271 if(depth == 1 && key) { //only look for metadata values when we are not nested and key != NULL
272 acodec = astream ? astream->codec : NULL;
273 vcodec = vstream ? vstream->codec : NULL;
275 if(amf_type == AMF_DATA_TYPE_BOOL) {
276 av_strlcpy(str_val, num_val > 0 ? "true" : "false", sizeof(str_val));
277 av_dict_set(&s->metadata, key, str_val, 0);
278 } else if(amf_type == AMF_DATA_TYPE_NUMBER) {
279 snprintf(str_val, sizeof(str_val), "%.f", num_val);
280 av_dict_set(&s->metadata, key, str_val, 0);
281 if(!strcmp(key, "duration")) s->duration = num_val * AV_TIME_BASE;
282 else if(!strcmp(key, "videodatarate") && vcodec && 0 <= (int)(num_val * 1024.0))
283 vcodec->bit_rate = num_val * 1024.0;
284 else if(!strcmp(key, "audiodatarate") && acodec && 0 <= (int)(num_val * 1024.0))
285 acodec->bit_rate = num_val * 1024.0;
286 } else if (amf_type == AMF_DATA_TYPE_STRING)
287 av_dict_set(&s->metadata, key, str_val, 0);
293 static int flv_read_metabody(AVFormatContext *s, int64_t next_pos) {
295 AVStream *stream, *astream, *vstream;
298 char buffer[11]; //only needs to hold the string "onMetaData". Anything longer is something we don't want.
304 //first object needs to be "onMetaData" string
306 if(type != AMF_DATA_TYPE_STRING || amf_get_string(ioc, buffer, sizeof(buffer)) < 0 || strcmp(buffer, "onMetaData"))
309 //find the streams now so that amf_parse_object doesn't need to do the lookup every time it is called.
310 for(i = 0; i < s->nb_streams; i++) {
311 stream = s->streams[i];
312 if (stream->codec->codec_type == AVMEDIA_TYPE_AUDIO) astream = stream;
313 else if(stream->codec->codec_type == AVMEDIA_TYPE_VIDEO) vstream = stream;
316 //parse the second object (we want a mixed array)
317 if(amf_parse_object(s, astream, vstream, buffer, next_pos, 0) < 0)
323 static AVStream *create_stream(AVFormatContext *s, int is_audio){
324 AVStream *st = av_new_stream(s, is_audio);
327 st->codec->codec_type = is_audio ? AVMEDIA_TYPE_AUDIO : AVMEDIA_TYPE_VIDEO;
328 av_set_pts_info(st, 32, 1, 1000); /* 32 bit pts in ms */
332 static int flv_read_header(AVFormatContext *s,
333 AVFormatParameters *ap)
338 flags = avio_r8(s->pb);
339 /* old flvtool cleared this field */
340 /* FIXME: better fix needed */
342 flags = FLV_HEADER_FLAG_HASVIDEO | FLV_HEADER_FLAG_HASAUDIO;
343 av_log(s, AV_LOG_WARNING, "Broken FLV file, which says no streams present, this might fail\n");
346 if((flags & (FLV_HEADER_FLAG_HASVIDEO|FLV_HEADER_FLAG_HASAUDIO))
347 != (FLV_HEADER_FLAG_HASVIDEO|FLV_HEADER_FLAG_HASAUDIO))
348 s->ctx_flags |= AVFMTCTX_NOHEADER;
350 if(flags & FLV_HEADER_FLAG_HASVIDEO){
351 if(!create_stream(s, 0))
352 return AVERROR(ENOMEM);
354 if(flags & FLV_HEADER_FLAG_HASAUDIO){
355 if(!create_stream(s, 1))
356 return AVERROR(ENOMEM);
359 offset = avio_rb32(s->pb);
360 avio_seek(s->pb, offset, SEEK_SET);
368 static int flv_get_extradata(AVFormatContext *s, AVStream *st, int size)
370 av_free(st->codec->extradata);
371 st->codec->extradata = av_mallocz(size + FF_INPUT_BUFFER_PADDING_SIZE);
372 if (!st->codec->extradata)
373 return AVERROR(ENOMEM);
374 st->codec->extradata_size = size;
375 avio_read(s->pb, st->codec->extradata, st->codec->extradata_size);
379 static int flv_read_packet(AVFormatContext *s, AVPacket *pkt)
381 FLVContext *flv = s->priv_data;
382 int ret, i, type, size, flags, is_audio;
384 int64_t dts, pts = AV_NOPTS_VALUE;
387 for(;;avio_skip(s->pb, 4)){ /* pkt size is repeated at end. skip it */
388 pos = avio_tell(s->pb);
389 type = avio_r8(s->pb);
390 size = avio_rb24(s->pb);
391 dts = avio_rb24(s->pb);
392 dts |= avio_r8(s->pb) << 24;
393 av_dlog(s, "type:%d, size:%d, dts:%"PRId64"\n", type, size, dts);
394 if (s->pb->eof_reached)
396 avio_skip(s->pb, 3); /* stream id, always 0 */
402 next= size + avio_tell(s->pb);
404 if (type == FLV_TAG_TYPE_AUDIO) {
406 flags = avio_r8(s->pb);
408 } else if (type == FLV_TAG_TYPE_VIDEO) {
410 flags = avio_r8(s->pb);
412 if ((flags & 0xf0) == 0x50) /* video info / command frame */
415 if (type == FLV_TAG_TYPE_META && size > 13+1+4)
416 flv_read_metabody(s, next);
417 else /* skip packet */
418 av_log(s, AV_LOG_DEBUG, "skipping flv packet: type %d, size %d, flags %d\n", type, size, flags);
420 avio_seek(s->pb, next, SEEK_SET);
424 /* skip empty data packets */
428 /* now find stream */
429 for(i=0;i<s->nb_streams;i++) {
431 if (st->id == is_audio)
434 if(i == s->nb_streams){
435 av_log(s, AV_LOG_ERROR, "invalid stream\n");
436 st= create_stream(s, is_audio);
437 s->ctx_flags &= ~AVFMTCTX_NOHEADER;
439 av_dlog(s, "%d %X %d \n", is_audio, flags, st->discard);
440 if( (st->discard >= AVDISCARD_NONKEY && !((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY || is_audio))
441 ||(st->discard >= AVDISCARD_BIDIR && ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_DISP_INTER && !is_audio))
442 || st->discard >= AVDISCARD_ALL
444 avio_seek(s->pb, next, SEEK_SET);
447 if ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY)
448 av_add_index_entry(st, pos, dts, size, 0, AVINDEX_KEYFRAME);
452 // if not streamed and no duration from metadata then seek to end to find the duration from the timestamps
453 if(s->pb->seekable && (!s->duration || s->duration==AV_NOPTS_VALUE)){
455 const int64_t pos= avio_tell(s->pb);
456 const int64_t fsize= avio_size(s->pb);
457 avio_seek(s->pb, fsize-4, SEEK_SET);
458 size= avio_rb32(s->pb);
459 avio_seek(s->pb, fsize-3-size, SEEK_SET);
460 if(size == avio_rb24(s->pb) + 11){
461 uint32_t ts = avio_rb24(s->pb);
462 ts |= avio_r8(s->pb) << 24;
463 s->duration = ts * (int64_t)AV_TIME_BASE / 1000;
465 avio_seek(s->pb, pos, SEEK_SET);
469 if(!st->codec->channels || !st->codec->sample_rate || !st->codec->bits_per_coded_sample) {
470 st->codec->channels = (flags & FLV_AUDIO_CHANNEL_MASK) == FLV_STEREO ? 2 : 1;
471 st->codec->sample_rate = (44100 << ((flags & FLV_AUDIO_SAMPLERATE_MASK) >> FLV_AUDIO_SAMPLERATE_OFFSET) >> 3);
472 st->codec->bits_per_coded_sample = (flags & FLV_AUDIO_SAMPLESIZE_MASK) ? 16 : 8;
474 if(!st->codec->codec_id){
475 flv_set_audio_codec(s, st, flags & FLV_AUDIO_CODECID_MASK);
478 size -= flv_set_video_codec(s, st, flags & FLV_VIDEO_CODECID_MASK);
481 if (st->codec->codec_id == CODEC_ID_AAC ||
482 st->codec->codec_id == CODEC_ID_H264) {
483 int type = avio_r8(s->pb);
485 if (st->codec->codec_id == CODEC_ID_H264) {
486 int32_t cts = (avio_rb24(s->pb)+0xff800000)^0xff800000; // sign extension
488 if (cts < 0) { // dts are wrong
490 av_log(s, AV_LOG_WARNING, "negative cts, previous timestamps might be wrong\n");
493 dts = AV_NOPTS_VALUE;
496 if ((ret = flv_get_extradata(s, st, size)) < 0)
498 if (st->codec->codec_id == CODEC_ID_AAC) {
499 MPEG4AudioConfig cfg;
500 ff_mpeg4audio_get_config(&cfg, st->codec->extradata,
501 st->codec->extradata_size);
502 st->codec->channels = cfg.channels;
503 if (cfg.ext_sample_rate)
504 st->codec->sample_rate = cfg.ext_sample_rate;
506 st->codec->sample_rate = cfg.sample_rate;
507 av_dlog(s, "mp4a config channels %d sample rate %d\n",
508 st->codec->channels, st->codec->sample_rate);
511 ret = AVERROR(EAGAIN);
516 /* skip empty data packets */
518 ret = AVERROR(EAGAIN);
522 ret= av_get_packet(s->pb, pkt, size);
526 /* note: we need to modify the packet size here to handle the last
530 pkt->pts = pts == AV_NOPTS_VALUE ? dts : pts;
531 pkt->stream_index = st->index;
533 if (is_audio || ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY))
534 pkt->flags |= AV_PKT_FLAG_KEY;
541 static int flv_read_seek(AVFormatContext *s, int stream_index,
542 int64_t ts, int flags)
544 return avio_seek_time(s->pb, stream_index, ts, flags);
547 #if 0 /* don't know enough to implement this */
548 static int flv_read_seek2(AVFormatContext *s, int stream_index,
549 int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
551 int ret = AVERROR(ENOSYS);
553 if (ts - min_ts > (uint64_t)(max_ts - ts)) flags |= AVSEEK_FLAG_BACKWARD;
555 if (!s->pb->seekable) {
556 if (stream_index < 0) {
557 stream_index = av_find_default_stream_index(s);
558 if (stream_index < 0)
561 /* timestamp for default must be expressed in AV_TIME_BASE units */
562 ts = av_rescale_rnd(ts, 1000, AV_TIME_BASE,
563 flags & AVSEEK_FLAG_BACKWARD ? AV_ROUND_DOWN : AV_ROUND_UP);
565 ret = avio_seek_time(s->pb, stream_index, ts, flags);
568 if (ret == AVERROR(ENOSYS))
569 ret = av_seek_frame(s, stream_index, ts, flags);
574 AVInputFormat ff_flv_demuxer = {
576 .long_name = NULL_IF_CONFIG_SMALL("FLV format"),
577 .priv_data_size = sizeof(FLVContext),
578 .read_probe = flv_probe,
579 .read_header = flv_read_header,
580 .read_packet = flv_read_packet,
581 .read_seek = flv_read_seek,
583 .read_seek2 = flv_read_seek2,
586 .value = CODEC_ID_FLV1,