/* * FLV demuxer * Copyright (c) 2003 The FFmpeg Project * * This demuxer will generate a 1 byte extradata for VP6F content. * It is composed of: * - upper 4bits: difference between encoded width and visible width * - lower 4bits: difference between encoded height and visible height * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include "libavutil/avstring.h" #include "libavcodec/bytestream.h" #include "libavcodec/mpeg4audio.h" #include "avformat.h" #include "flv.h" typedef struct { int wrong_dts; ///< wrong dts due to negative cts } FLVContext; static int flv_probe(AVProbeData *p) { const uint8_t *d; d = p->buf; if (d[0] == 'F' && d[1] == 'L' && d[2] == 'V' && d[3] < 5 && d[5]==0 && AV_RB32(d+5)>8) { return AVPROBE_SCORE_MAX; } return 0; } static void flv_set_audio_codec(AVFormatContext *s, AVStream *astream, int flv_codecid) { AVCodecContext *acodec = astream->codec; switch(flv_codecid) { //no distinction between S16 and S8 PCM codec flags case FLV_CODECID_PCM: acodec->codec_id = acodec->bits_per_coded_sample == 8 ? CODEC_ID_PCM_U8 : #if HAVE_BIGENDIAN CODEC_ID_PCM_S16BE; #else CODEC_ID_PCM_S16LE; #endif break; case FLV_CODECID_PCM_LE: acodec->codec_id = acodec->bits_per_coded_sample == 8 ? CODEC_ID_PCM_U8 : CODEC_ID_PCM_S16LE; break; case FLV_CODECID_AAC : acodec->codec_id = CODEC_ID_AAC; break; case FLV_CODECID_ADPCM: acodec->codec_id = CODEC_ID_ADPCM_SWF; break; case FLV_CODECID_SPEEX: acodec->codec_id = CODEC_ID_SPEEX; acodec->sample_rate = 16000; break; case FLV_CODECID_MP3 : acodec->codec_id = CODEC_ID_MP3 ; astream->need_parsing = AVSTREAM_PARSE_FULL; break; case FLV_CODECID_NELLYMOSER_8KHZ_MONO: acodec->sample_rate = 8000; //in case metadata does not otherwise declare samplerate acodec->codec_id = CODEC_ID_NELLYMOSER; break; case FLV_CODECID_NELLYMOSER_16KHZ_MONO: acodec->sample_rate = 16000; acodec->codec_id = CODEC_ID_NELLYMOSER; break; case FLV_CODECID_NELLYMOSER: acodec->codec_id = CODEC_ID_NELLYMOSER; break; default: av_log(s, AV_LOG_INFO, "Unsupported audio codec (%x)\n", flv_codecid >> FLV_AUDIO_CODECID_OFFSET); acodec->codec_tag = flv_codecid >> FLV_AUDIO_CODECID_OFFSET; } } static int flv_set_video_codec(AVFormatContext *s, AVStream *vstream, int flv_codecid) { AVCodecContext *vcodec = vstream->codec; switch(flv_codecid) { case FLV_CODECID_H263 : vcodec->codec_id = CODEC_ID_FLV1 ; break; case FLV_CODECID_SCREEN: vcodec->codec_id = CODEC_ID_FLASHSV; break; case FLV_CODECID_SCREEN2: vcodec->codec_id = CODEC_ID_FLASHSV2; break; case FLV_CODECID_VP6 : vcodec->codec_id = CODEC_ID_VP6F ; case FLV_CODECID_VP6A : if(flv_codecid == FLV_CODECID_VP6A) vcodec->codec_id = CODEC_ID_VP6A; if(vcodec->extradata_size != 1) { vcodec->extradata_size = 1; vcodec->extradata = av_malloc(1); } vcodec->extradata[0] = get_byte(s->pb); return 1; // 1 byte body size adjustment for flv_read_packet() case FLV_CODECID_H264: vcodec->codec_id = CODEC_ID_H264; return 3; // not 4, reading packet type will consume one byte default: av_log(s, AV_LOG_INFO, "Unsupported video codec (%x)\n", flv_codecid); vcodec->codec_tag = flv_codecid; } return 0; } static int amf_get_string(ByteIOContext *ioc, char *buffer, int buffsize) { int length = get_be16(ioc); if(length >= buffsize) { url_fskip(ioc, length); return -1; } get_buffer(ioc, buffer, length); buffer[length] = '\0'; return length; } static int amf_parse_object(AVFormatContext *s, AVStream *astream, AVStream *vstream, const char *key, int64_t max_pos, int depth) { AVCodecContext *acodec, *vcodec; ByteIOContext *ioc; AMFDataType amf_type; char str_val[256]; double num_val; num_val = 0; ioc = s->pb; amf_type = get_byte(ioc); switch(amf_type) { case AMF_DATA_TYPE_NUMBER: num_val = av_int2dbl(get_be64(ioc)); break; case AMF_DATA_TYPE_BOOL: num_val = get_byte(ioc); break; case AMF_DATA_TYPE_STRING: if(amf_get_string(ioc, str_val, sizeof(str_val)) < 0) return -1; break; case AMF_DATA_TYPE_OBJECT: { unsigned int keylen; while(url_ftell(ioc) < max_pos - 2 && (keylen = get_be16(ioc))) { url_fskip(ioc, keylen); //skip key string if(amf_parse_object(s, NULL, NULL, NULL, max_pos, depth + 1) < 0) return -1; //if we couldn't skip, bomb out. } if(get_byte(ioc) != AMF_END_OF_OBJECT) return -1; } break; case AMF_DATA_TYPE_NULL: case AMF_DATA_TYPE_UNDEFINED: case AMF_DATA_TYPE_UNSUPPORTED: break; //these take up no additional space case AMF_DATA_TYPE_MIXEDARRAY: url_fskip(ioc, 4); //skip 32-bit max array index while(url_ftell(ioc) < max_pos - 2 && amf_get_string(ioc, str_val, sizeof(str_val)) > 0) { //this is the only case in which we would want a nested parse to not skip over the object if(amf_parse_object(s, astream, vstream, str_val, max_pos, depth + 1) < 0) return -1; } if(get_byte(ioc) != AMF_END_OF_OBJECT) return -1; break; case AMF_DATA_TYPE_ARRAY: { unsigned int arraylen, i; arraylen = get_be32(ioc); for(i = 0; i < arraylen && url_ftell(ioc) < max_pos - 1; i++) { if(amf_parse_object(s, NULL, NULL, NULL, max_pos, depth + 1) < 0) return -1; //if we couldn't skip, bomb out. } } break; case AMF_DATA_TYPE_DATE: url_fskip(ioc, 8 + 2); //timestamp (double) and UTC offset (int16) break; default: //unsupported type, we couldn't skip return -1; } if(depth == 1 && key) { //only look for metadata values when we are not nested and key != NULL acodec = astream ? astream->codec : NULL; vcodec = vstream ? vstream->codec : NULL; if(amf_type == AMF_DATA_TYPE_BOOL) { av_strlcpy(str_val, num_val > 0 ? "true" : "false", sizeof(str_val)); av_metadata_set2(&s->metadata, key, str_val, 0); } else if(amf_type == AMF_DATA_TYPE_NUMBER) { snprintf(str_val, sizeof(str_val), "%.f", num_val); av_metadata_set2(&s->metadata, key, str_val, 0); if(!strcmp(key, "duration")) s->duration = num_val * AV_TIME_BASE; else if(!strcmp(key, "videodatarate") && vcodec && 0 <= (int)(num_val * 1024.0)) vcodec->bit_rate = num_val * 1024.0; else if(!strcmp(key, "audiodatarate") && acodec && 0 <= (int)(num_val * 1024.0)) acodec->bit_rate = num_val * 1024.0; } else if (amf_type == AMF_DATA_TYPE_STRING) av_metadata_set2(&s->metadata, key, str_val, 0); } return 0; } static int flv_read_metabody(AVFormatContext *s, int64_t next_pos) { AMFDataType type; AVStream *stream, *astream, *vstream; ByteIOContext *ioc; int i; char buffer[11]; //only needs to hold the string "onMetaData". Anything longer is something we don't want. astream = NULL; vstream = NULL; ioc = s->pb; //first object needs to be "onMetaData" string type = get_byte(ioc); if(type != AMF_DATA_TYPE_STRING || amf_get_string(ioc, buffer, sizeof(buffer)) < 0 || strcmp(buffer, "onMetaData")) return -1; //find the streams now so that amf_parse_object doesn't need to do the lookup every time it is called. for(i = 0; i < s->nb_streams; i++) { stream = s->streams[i]; if (stream->codec->codec_type == AVMEDIA_TYPE_AUDIO) astream = stream; else if(stream->codec->codec_type == AVMEDIA_TYPE_VIDEO) vstream = stream; } //parse the second object (we want a mixed array) if(amf_parse_object(s, astream, vstream, buffer, next_pos, 0) < 0) return -1; return 0; } static AVStream *create_stream(AVFormatContext *s, int is_audio){ AVStream *st = av_new_stream(s, is_audio); if (!st) return NULL; st->codec->codec_type = is_audio ? AVMEDIA_TYPE_AUDIO : AVMEDIA_TYPE_VIDEO; av_set_pts_info(st, 32, 1, 1000); /* 32 bit pts in ms */ return st; } static int flv_read_header(AVFormatContext *s, AVFormatParameters *ap) { int offset, flags; url_fskip(s->pb, 4); flags = get_byte(s->pb); /* old flvtool cleared this field */ /* FIXME: better fix needed */ if (!flags) { flags = FLV_HEADER_FLAG_HASVIDEO | FLV_HEADER_FLAG_HASAUDIO; av_log(s, AV_LOG_WARNING, "Broken FLV file, which says no streams present, this might fail\n"); } if((flags & (FLV_HEADER_FLAG_HASVIDEO|FLV_HEADER_FLAG_HASAUDIO)) != (FLV_HEADER_FLAG_HASVIDEO|FLV_HEADER_FLAG_HASAUDIO)) s->ctx_flags |= AVFMTCTX_NOHEADER; if(flags & FLV_HEADER_FLAG_HASVIDEO){ if(!create_stream(s, 0)) return AVERROR(ENOMEM); } if(flags & FLV_HEADER_FLAG_HASAUDIO){ if(!create_stream(s, 1)) return AVERROR(ENOMEM); } offset = get_be32(s->pb); url_fseek(s->pb, offset, SEEK_SET); url_fskip(s->pb, 4); s->start_time = 0; return 0; } static int flv_get_extradata(AVFormatContext *s, AVStream *st, int size) { av_free(st->codec->extradata); st->codec->extradata = av_mallocz(size + FF_INPUT_BUFFER_PADDING_SIZE); if (!st->codec->extradata) return AVERROR(ENOMEM); st->codec->extradata_size = size; get_buffer(s->pb, st->codec->extradata, st->codec->extradata_size); return 0; } static int flv_read_packet(AVFormatContext *s, AVPacket *pkt) { FLVContext *flv = s->priv_data; int ret, i, type, size, flags, is_audio; int64_t next, pos; int64_t dts, pts = AV_NOPTS_VALUE; AVStream *st = NULL; for(;;url_fskip(s->pb, 4)){ /* pkt size is repeated at end. skip it */ pos = url_ftell(s->pb); type = get_byte(s->pb); size = get_be24(s->pb); dts = get_be24(s->pb); dts |= get_byte(s->pb) << 24; // av_log(s, AV_LOG_DEBUG, "type:%d, size:%d, dts:%d\n", type, size, dts); if (url_feof(s->pb)) return AVERROR_EOF; url_fskip(s->pb, 3); /* stream id, always 0 */ flags = 0; if(size == 0) continue; next= size + url_ftell(s->pb); if (type == FLV_TAG_TYPE_AUDIO) { is_audio=1; flags = get_byte(s->pb); size--; } else if (type == FLV_TAG_TYPE_VIDEO) { is_audio=0; flags = get_byte(s->pb); size--; if ((flags & 0xf0) == 0x50) /* video info / command frame */ goto skip; } else { if (type == FLV_TAG_TYPE_META && size > 13+1+4) flv_read_metabody(s, next); else /* skip packet */ av_log(s, AV_LOG_DEBUG, "skipping flv packet: type %d, size %d, flags %d\n", type, size, flags); skip: url_fseek(s->pb, next, SEEK_SET); continue; } /* skip empty data packets */ if (!size) continue; /* now find stream */ for(i=0;i<s->nb_streams;i++) { st = s->streams[i]; if (st->id == is_audio) break; } if(i == s->nb_streams){ av_log(s, AV_LOG_ERROR, "invalid stream\n"); st= create_stream(s, is_audio); s->ctx_flags &= ~AVFMTCTX_NOHEADER; } // av_log(s, AV_LOG_DEBUG, "%d %X %d \n", is_audio, flags, st->discard); if( (st->discard >= AVDISCARD_NONKEY && !((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY || is_audio)) ||(st->discard >= AVDISCARD_BIDIR && ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_DISP_INTER && !is_audio)) || st->discard >= AVDISCARD_ALL ){ url_fseek(s->pb, next, SEEK_SET); continue; } if ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY) av_add_index_entry(st, pos, dts, size, 0, AVINDEX_KEYFRAME); break; } // if not streamed and no duration from metadata then seek to end to find the duration from the timestamps if(!url_is_streamed(s->pb) && (!s->duration || s->duration==AV_NOPTS_VALUE)){ int size; const int64_t pos= url_ftell(s->pb); const int64_t fsize= url_fsize(s->pb); url_fseek(s->pb, fsize-4, SEEK_SET); size= get_be32(s->pb); url_fseek(s->pb, fsize-3-size, SEEK_SET); if(size == get_be24(s->pb) + 11){ uint32_t ts = get_be24(s->pb); ts |= get_byte(s->pb) << 24; s->duration = ts * (int64_t)AV_TIME_BASE / 1000; } url_fseek(s->pb, pos, SEEK_SET); } if(is_audio){ if(!st->codec->channels || !st->codec->sample_rate || !st->codec->bits_per_coded_sample) { st->codec->channels = (flags & FLV_AUDIO_CHANNEL_MASK) == FLV_STEREO ? 2 : 1; st->codec->sample_rate = (44100 << ((flags & FLV_AUDIO_SAMPLERATE_MASK) >> FLV_AUDIO_SAMPLERATE_OFFSET) >> 3); st->codec->bits_per_coded_sample = (flags & FLV_AUDIO_SAMPLESIZE_MASK) ? 16 : 8; } if(!st->codec->codec_id){ flv_set_audio_codec(s, st, flags & FLV_AUDIO_CODECID_MASK); } }else{ size -= flv_set_video_codec(s, st, flags & FLV_VIDEO_CODECID_MASK); } if (st->codec->codec_id == CODEC_ID_AAC || st->codec->codec_id == CODEC_ID_H264) { int type = get_byte(s->pb); size--; if (st->codec->codec_id == CODEC_ID_H264) { int32_t cts = (get_be24(s->pb)+0xff800000)^0xff800000; // sign extension pts = dts + cts; if (cts < 0) { // dts are wrong flv->wrong_dts = 1; av_log(s, AV_LOG_WARNING, "negative cts, previous timestamps might be wrong\n"); } if (flv->wrong_dts) dts = AV_NOPTS_VALUE; } if (type == 0) { if ((ret = flv_get_extradata(s, st, size)) < 0) return ret; if (st->codec->codec_id == CODEC_ID_AAC) { MPEG4AudioConfig cfg; ff_mpeg4audio_get_config(&cfg, st->codec->extradata, st->codec->extradata_size); st->codec->channels = cfg.channels; if (cfg.ext_sample_rate) st->codec->sample_rate = cfg.ext_sample_rate; else st->codec->sample_rate = cfg.sample_rate; dprintf(s, "mp4a config channels %d sample rate %d\n", st->codec->channels, st->codec->sample_rate); } ret = AVERROR(EAGAIN); goto leave; } } /* skip empty data packets */ if (!size) { ret = AVERROR(EAGAIN); goto leave; } ret= av_get_packet(s->pb, pkt, size); if (ret < 0) { return AVERROR(EIO); } /* note: we need to modify the packet size here to handle the last packet */ pkt->size = ret; pkt->dts = dts; pkt->pts = pts == AV_NOPTS_VALUE ? dts : pts; pkt->stream_index = st->index; if (is_audio || ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY)) pkt->flags |= AV_PKT_FLAG_KEY; leave: url_fskip(s->pb, 4); return ret; } static int flv_read_seek(AVFormatContext *s, int stream_index, int64_t ts, int flags) { return av_url_read_fseek(s->pb, stream_index, ts, flags); } #if 0 /* don't know enough to implement this */ static int flv_read_seek2(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags) { int ret = AVERROR(ENOSYS); if (ts - min_ts > (uint64_t)(max_ts - ts)) flags |= AVSEEK_FLAG_BACKWARD; if (url_is_streamed(s->pb)) { if (stream_index < 0) { stream_index = av_find_default_stream_index(s); if (stream_index < 0) return -1; /* timestamp for default must be expressed in AV_TIME_BASE units */ ts = av_rescale_rnd(ts, 1000, AV_TIME_BASE, flags & AVSEEK_FLAG_BACKWARD ? AV_ROUND_DOWN : AV_ROUND_UP); } ret = av_url_read_fseek(s->pb, stream_index, ts, flags); } if (ret == AVERROR(ENOSYS)) ret = av_seek_frame(s, stream_index, ts, flags); return ret; } #endif AVInputFormat flv_demuxer = { "flv", NULL_IF_CONFIG_SMALL("FLV format"), sizeof(FLVContext), flv_probe, flv_read_header, flv_read_packet, .read_seek = flv_read_seek, #if 0 .read_seek2 = flv_read_seek2, #endif .extensions = "flv", .value = CODEC_ID_FLV1, };