/* * 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 "avformat.h" #include "flv.h" 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) { 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_BE: acodec->codec_id = acodec->bits_per_sample == 8 ? CODEC_ID_PCM_S8 : CODEC_ID_PCM_S16BE; break; case FLV_CODECID_PCM_LE: acodec->codec_id = acodec->bits_per_sample == 8 ? CODEC_ID_PCM_S8 : CODEC_ID_PCM_S16LE; break; case FLV_CODECID_ADPCM: acodec->codec_id = CODEC_ID_ADPCM_SWF; break; case FLV_CODECID_MP3 : acodec->codec_id = CODEC_ID_MP3 ; astream->need_parsing = AVSTREAM_PARSE_FULL; break; case FLV_CODECID_NELLYMOSER_8HZ_MONO: acodec->sample_rate = 8000; //in case metadata does not otherwise declare samplerate case FLV_CODECID_NELLYMOSER: 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_VP6 : vcodec->codec_id = CODEC_ID_VP6F ; 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() 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, unsigned int 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) { if(!strcmp(key, "stereo") && acodec) acodec->channels = num_val > 0 ? 2 : 1; } else if(amf_type == AMF_DATA_TYPE_NUMBER) { if(!strcmp(key, "duration")) s->duration = num_val * AV_TIME_BASE; // else if(!strcmp(key, "width") && vcodec && num_val > 0) vcodec->width = num_val; // else if(!strcmp(key, "height") && vcodec && num_val > 0) vcodec->height = num_val; else if(!strcmp(key, "audiocodecid") && acodec) flv_set_audio_codec(s, astream, (int)num_val << FLV_AUDIO_CODECID_OFFSET); else if(!strcmp(key, "videocodecid") && vcodec) flv_set_video_codec(s, vstream, (int)num_val); else if(!strcmp(key, "audiosamplesize") && acodec && num_val >= 0) { acodec->bits_per_sample = num_val; //we may have to rewrite a previously read codecid because FLV only marks PCM endianness. if(num_val == 8 && (acodec->codec_id == CODEC_ID_PCM_S16BE || acodec->codec_id == CODEC_ID_PCM_S16LE)) acodec->codec_id = CODEC_ID_PCM_S8; } else if(!strcmp(key, "audiosamplerate") && acodec && num_val >= 0) { //some tools, like FLVTool2, write consistently approximate metadata sample rates switch((int)num_val) { case 44000: acodec->sample_rate = 44100 ; break; case 22000: acodec->sample_rate = 22050 ; break; case 11000: acodec->sample_rate = 11025 ; break; case 5000 : acodec->sample_rate = 5512 ; break; default : acodec->sample_rate = num_val; } } } } return 0; } static int flv_read_metabody(AVFormatContext *s, unsigned int next_pos) { AMFDataType type; AVStream *stream, *astream, *vstream; ByteIOContext *ioc; int i, keylen; char buffer[11]; //only needs to hold the string "onMetaData". Anything longer is something we don't want. astream = NULL; vstream = NULL; keylen = 0; 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 == CODEC_TYPE_AUDIO) astream = stream; else if(stream->codec->codec_type == CODEC_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 int flv_read_header(AVFormatContext *s, AVFormatParameters *ap) { int offset, flags; AVStream *st; 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){ st = av_new_stream(s, 0); if (!st) return AVERROR_NOMEM; st->codec->codec_type = CODEC_TYPE_VIDEO; av_set_pts_info(st, 24, 1, 1000); /* 24 bit pts in ms */ } if(flags & FLV_HEADER_FLAG_HASAUDIO){ st = av_new_stream(s, 1); if (!st) return AVERROR_NOMEM; st->codec->codec_type = CODEC_TYPE_AUDIO; av_set_pts_info(st, 24, 1, 1000); /* 24 bit pts in ms */ } offset = get_be32(&s->pb); url_fseek(&s->pb, offset, SEEK_SET); s->start_time = 0; return 0; } static int flv_read_packet(AVFormatContext *s, AVPacket *pkt) { int ret, i, type, size, pts, flags, is_audio, next, pos; AVStream *st = NULL; for(;;){ pos = url_ftell(&s->pb); url_fskip(&s->pb, 4); /* size of previous packet */ type = get_byte(&s->pb); size = get_be24(&s->pb); pts = get_be24(&s->pb); // av_log(s, AV_LOG_DEBUG, "type:%d, size:%d, pts:%d\n", type, size, pts); if (url_feof(&s->pb)) return AVERROR_IO; url_fskip(&s->pb, 4); /* reserved */ 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); } else if (type == FLV_TAG_TYPE_VIDEO) { is_audio=0; flags = get_byte(&s->pb); } else { if (type == FLV_TAG_TYPE_META && size > 13+1+4) flv_read_metabody(s, next); else /* skip packet */ av_log(s, AV_LOG_ERROR, "skipping flv packet: type %d, size %d, flags %d\n", type, size, flags); url_fseek(&s->pb, next, SEEK_SET); 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(NULL, AV_LOG_ERROR, "invalid stream\n"); url_fseek(&s->pb, next, SEEK_SET); continue; } // av_log(NULL, 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, pts, 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==AV_NOPTS_VALUE){ int size; const int pos= url_ftell(&s->pb); const int 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){ s->duration= get_be24(&s->pb) * (int64_t)AV_TIME_BASE / 1000; } url_fseek(&s->pb, pos, SEEK_SET); } if(is_audio){ if(!st->codec->sample_rate || !st->codec->bits_per_sample || (!st->codec->codec_id && !st->codec->codec_tag)) { st->codec->channels = (flags & FLV_AUDIO_CHANNEL_MASK) == FLV_STEREO ? 2 : 1; if((flags & FLV_AUDIO_CODECID_MASK) == FLV_CODECID_NELLYMOSER_8HZ_MONO) st->codec->sample_rate= 8000; else st->codec->sample_rate = (44100 << ((flags & FLV_AUDIO_SAMPLERATE_MASK) >> FLV_AUDIO_SAMPLERATE_OFFSET) >> 3); st->codec->bits_per_sample = (flags & FLV_AUDIO_SAMPLESIZE_MASK) ? 16 : 8; flv_set_audio_codec(s, st, flags & FLV_AUDIO_CODECID_MASK); } }else{ size -= flv_set_video_codec(s, st, flags & FLV_VIDEO_CODECID_MASK); } ret= av_get_packet(&s->pb, pkt, size - 1); if (ret <= 0) { return AVERROR_IO; } /* note: we need to modify the packet size here to handle the last packet */ pkt->size = ret; pkt->pts = pts; pkt->stream_index = st->index; if (is_audio || ((flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_KEY)) pkt->flags |= PKT_FLAG_KEY; return ret; } static int flv_read_close(AVFormatContext *s) { return 0; } static int flv_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags) { AVStream *st = s->streams[stream_index]; int index = av_index_search_timestamp(st, timestamp, flags); if (index < 0) return -1; url_fseek(&s->pb, st->index_entries[index].pos, SEEK_SET); return 0; } AVInputFormat flv_demuxer = { "flv", "flv format", 0, flv_probe, flv_read_header, flv_read_packet, flv_read_close, flv_read_seek, .extensions = "flv", .value = CODEC_ID_FLV1, };