| /* |
| * Raw FLAC demuxer |
| * Copyright (c) 2001 Fabrice Bellard |
| * |
| * 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 "libavcodec/flac.h" |
| #include "avformat.h" |
| #include "flac_picture.h" |
| #include "internal.h" |
| #include "rawdec.h" |
| #include "oggdec.h" |
| #include "vorbiscomment.h" |
| #include "replaygain.h" |
| |
| #define SEEKPOINT_SIZE 18 |
| |
| typedef struct FLACDecContext { |
| AVClass *class; |
| int raw_packet_size; |
| int found_seektable; |
| } FLACDecContext; |
| |
| static void reset_index_position(int64_t metadata_head_size, AVStream *st) |
| { |
| /* the real seek index offset should be the size of metadata blocks with the offset in the frame blocks */ |
| int i; |
| for(i=0; i<st->nb_index_entries; i++) { |
| st->index_entries[i].pos += metadata_head_size; |
| } |
| } |
| |
| static int flac_read_header(AVFormatContext *s) |
| { |
| int ret, metadata_last=0, metadata_type, metadata_size, found_streaminfo=0; |
| uint8_t header[4]; |
| uint8_t *buffer=NULL; |
| FLACDecContext *flac = s->priv_data; |
| AVStream *st = avformat_new_stream(s, NULL); |
| if (!st) |
| return AVERROR(ENOMEM); |
| st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO; |
| st->codecpar->codec_id = AV_CODEC_ID_FLAC; |
| st->need_parsing = AVSTREAM_PARSE_FULL_RAW; |
| /* the parameters will be extracted from the compressed bitstream */ |
| |
| /* if fLaC marker is not found, assume there is no header */ |
| if (avio_rl32(s->pb) != MKTAG('f','L','a','C')) { |
| avio_seek(s->pb, -4, SEEK_CUR); |
| return 0; |
| } |
| |
| /* process metadata blocks */ |
| while (!avio_feof(s->pb) && !metadata_last) { |
| if (avio_read(s->pb, header, 4) != 4) |
| return AVERROR(AVERROR_INVALIDDATA); |
| flac_parse_block_header(header, &metadata_last, &metadata_type, |
| &metadata_size); |
| switch (metadata_type) { |
| /* allocate and read metadata block for supported types */ |
| case FLAC_METADATA_TYPE_STREAMINFO: |
| case FLAC_METADATA_TYPE_CUESHEET: |
| case FLAC_METADATA_TYPE_PICTURE: |
| case FLAC_METADATA_TYPE_VORBIS_COMMENT: |
| case FLAC_METADATA_TYPE_SEEKTABLE: |
| buffer = av_mallocz(metadata_size + AV_INPUT_BUFFER_PADDING_SIZE); |
| if (!buffer) { |
| return AVERROR(ENOMEM); |
| } |
| if (avio_read(s->pb, buffer, metadata_size) != metadata_size) { |
| RETURN_ERROR(AVERROR(EIO)); |
| } |
| break; |
| /* skip metadata block for unsupported types */ |
| default: |
| ret = avio_skip(s->pb, metadata_size); |
| if (ret < 0) |
| return ret; |
| } |
| |
| if (metadata_type == FLAC_METADATA_TYPE_STREAMINFO) { |
| uint32_t samplerate; |
| uint64_t samples; |
| |
| /* STREAMINFO can only occur once */ |
| if (found_streaminfo) { |
| RETURN_ERROR(AVERROR_INVALIDDATA); |
| } |
| if (metadata_size != FLAC_STREAMINFO_SIZE) { |
| RETURN_ERROR(AVERROR_INVALIDDATA); |
| } |
| found_streaminfo = 1; |
| st->codecpar->extradata = buffer; |
| st->codecpar->extradata_size = metadata_size; |
| buffer = NULL; |
| |
| /* get sample rate and sample count from STREAMINFO header; |
| * other parameters will be extracted by the parser */ |
| samplerate = AV_RB24(st->codecpar->extradata + 10) >> 4; |
| samples = (AV_RB64(st->codecpar->extradata + 13) >> 24) & ((1ULL << 36) - 1); |
| |
| /* set time base and duration */ |
| if (samplerate > 0) { |
| avpriv_set_pts_info(st, 64, 1, samplerate); |
| if (samples > 0) |
| st->duration = samples; |
| } |
| } else if (metadata_type == FLAC_METADATA_TYPE_CUESHEET) { |
| uint8_t isrc[13]; |
| uint64_t start; |
| const uint8_t *offset; |
| int i, chapters, track, ti; |
| if (metadata_size < 431) |
| RETURN_ERROR(AVERROR_INVALIDDATA); |
| offset = buffer + 395; |
| chapters = bytestream_get_byte(&offset) - 1; |
| if (chapters <= 0) |
| RETURN_ERROR(AVERROR_INVALIDDATA); |
| for (i = 0; i < chapters; i++) { |
| if (offset + 36 - buffer > metadata_size) |
| RETURN_ERROR(AVERROR_INVALIDDATA); |
| start = bytestream_get_be64(&offset); |
| track = bytestream_get_byte(&offset); |
| bytestream_get_buffer(&offset, isrc, 12); |
| isrc[12] = 0; |
| offset += 14; |
| ti = bytestream_get_byte(&offset); |
| if (ti <= 0) RETURN_ERROR(AVERROR_INVALIDDATA); |
| offset += ti * 12; |
| avpriv_new_chapter(s, track, st->time_base, start, AV_NOPTS_VALUE, isrc); |
| } |
| av_freep(&buffer); |
| } else if (metadata_type == FLAC_METADATA_TYPE_PICTURE) { |
| ret = ff_flac_parse_picture(s, buffer, metadata_size); |
| av_freep(&buffer); |
| if (ret < 0) { |
| av_log(s, AV_LOG_ERROR, "Error parsing attached picture.\n"); |
| return ret; |
| } |
| } else if (metadata_type == FLAC_METADATA_TYPE_SEEKTABLE) { |
| const uint8_t *seekpoint = buffer; |
| int i, seek_point_count = metadata_size/SEEKPOINT_SIZE; |
| flac->found_seektable = 1; |
| if ((s->flags&AVFMT_FLAG_FAST_SEEK)) { |
| for(i=0; i<seek_point_count; i++) { |
| int64_t timestamp = bytestream_get_be64(&seekpoint); |
| int64_t pos = bytestream_get_be64(&seekpoint); |
| /* skip number of samples */ |
| bytestream_get_be16(&seekpoint); |
| av_add_index_entry(st, pos, timestamp, 0, 0, AVINDEX_KEYFRAME); |
| } |
| } |
| av_freep(&buffer); |
| } |
| else { |
| |
| /* STREAMINFO must be the first block */ |
| if (!found_streaminfo) { |
| RETURN_ERROR(AVERROR_INVALIDDATA); |
| } |
| /* process supported blocks other than STREAMINFO */ |
| if (metadata_type == FLAC_METADATA_TYPE_VORBIS_COMMENT) { |
| AVDictionaryEntry *chmask; |
| |
| ret = ff_vorbis_comment(s, &s->metadata, buffer, metadata_size, 1); |
| if (ret < 0) { |
| av_log(s, AV_LOG_WARNING, "error parsing VorbisComment metadata\n"); |
| } else if (ret > 0) { |
| s->event_flags |= AVFMT_EVENT_FLAG_METADATA_UPDATED; |
| } |
| |
| /* parse the channels mask if present */ |
| chmask = av_dict_get(s->metadata, "WAVEFORMATEXTENSIBLE_CHANNEL_MASK", NULL, 0); |
| if (chmask) { |
| uint64_t mask = strtol(chmask->value, NULL, 0); |
| if (!mask || mask & ~0x3ffffULL) { |
| av_log(s, AV_LOG_WARNING, |
| "Invalid value of WAVEFORMATEXTENSIBLE_CHANNEL_MASK\n"); |
| } else { |
| st->codecpar->channel_layout = mask; |
| av_dict_set(&s->metadata, "WAVEFORMATEXTENSIBLE_CHANNEL_MASK", NULL, 0); |
| } |
| } |
| } |
| av_freep(&buffer); |
| } |
| } |
| |
| ret = ff_replaygain_export(st, s->metadata); |
| if (ret < 0) |
| return ret; |
| |
| reset_index_position(avio_tell(s->pb), st); |
| return 0; |
| |
| fail: |
| av_free(buffer); |
| return ret; |
| } |
| |
| static int raw_flac_probe(const AVProbeData *p) |
| { |
| if ((p->buf[2] & 0xF0) == 0) // blocksize code invalid |
| return 0; |
| if ((p->buf[2] & 0x0F) == 0x0F) // sample rate code invalid |
| return 0; |
| if ((p->buf[3] & 0xF0) >= FLAC_MAX_CHANNELS + FLAC_CHMODE_MID_SIDE << 4) |
| // channel mode invalid |
| return 0; |
| if ((p->buf[3] & 0x06) == 0x06) // bits per sample code invalid |
| return 0; |
| if ((p->buf[3] & 0x01) == 0x01) // reserved bit set |
| return 0; |
| return AVPROBE_SCORE_EXTENSION / 4 + 1; |
| } |
| |
| static int flac_probe(const AVProbeData *p) |
| { |
| if ((AV_RB16(p->buf) & 0xFFFE) == 0xFFF8) |
| return raw_flac_probe(p); |
| |
| /* file header + metadata header + checked bytes of streaminfo */ |
| if (p->buf_size >= 4 + 4 + 13) { |
| int type = p->buf[4] & 0x7f; |
| int size = AV_RB24(p->buf + 5); |
| int min_block_size = AV_RB16(p->buf + 8); |
| int max_block_size = AV_RB16(p->buf + 10); |
| int sample_rate = AV_RB24(p->buf + 18) >> 4; |
| |
| if (memcmp(p->buf, "fLaC", 4)) |
| return 0; |
| if (type == FLAC_METADATA_TYPE_STREAMINFO && |
| size == FLAC_STREAMINFO_SIZE && |
| min_block_size >= 16 && |
| max_block_size >= min_block_size && |
| sample_rate && sample_rate <= 655350) |
| return AVPROBE_SCORE_MAX; |
| return AVPROBE_SCORE_EXTENSION; |
| } |
| |
| return 0; |
| } |
| |
| static av_unused int64_t flac_read_timestamp(AVFormatContext *s, int stream_index, |
| int64_t *ppos, int64_t pos_limit) |
| { |
| AVPacket pkt; |
| AVStream *st = s->streams[stream_index]; |
| AVCodecParserContext *parser; |
| int ret; |
| int64_t pts = AV_NOPTS_VALUE; |
| |
| if (avio_seek(s->pb, *ppos, SEEK_SET) < 0) |
| return AV_NOPTS_VALUE; |
| |
| av_init_packet(&pkt); |
| parser = av_parser_init(st->codecpar->codec_id); |
| if (!parser){ |
| return AV_NOPTS_VALUE; |
| } |
| parser->flags |= PARSER_FLAG_USE_CODEC_TS; |
| |
| for (;;){ |
| uint8_t *data; |
| int size; |
| |
| ret = ff_raw_read_partial_packet(s, &pkt); |
| if (ret < 0){ |
| if (ret == AVERROR(EAGAIN)) |
| continue; |
| else { |
| av_packet_unref(&pkt); |
| av_assert1(!pkt.size); |
| } |
| } |
| av_parser_parse2(parser, st->internal->avctx, |
| &data, &size, pkt.data, pkt.size, |
| pkt.pts, pkt.dts, *ppos); |
| |
| av_packet_unref(&pkt); |
| if (size) { |
| if (parser->pts != AV_NOPTS_VALUE){ |
| // seeking may not have started from beginning of a frame |
| // calculate frame start position from next frame backwards |
| *ppos = parser->next_frame_offset - size; |
| pts = parser->pts; |
| break; |
| } |
| } else if (ret < 0) |
| break; |
| } |
| av_parser_close(parser); |
| return pts; |
| } |
| |
| static int flac_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags) { |
| int index; |
| int64_t pos; |
| AVIndexEntry e; |
| FLACDecContext *flac = s->priv_data; |
| |
| if (!flac->found_seektable || !(s->flags&AVFMT_FLAG_FAST_SEEK)) { |
| return -1; |
| } |
| |
| index = av_index_search_timestamp(s->streams[0], timestamp, flags); |
| if(index<0 || index >= s->streams[0]->nb_index_entries) |
| return -1; |
| |
| e = s->streams[0]->index_entries[index]; |
| pos = avio_seek(s->pb, e.pos, SEEK_SET); |
| if (pos >= 0) { |
| return 0; |
| } |
| return -1; |
| } |
| |
| FF_RAW_DEMUXER_CLASS(flac) |
| AVInputFormat ff_flac_demuxer = { |
| .name = "flac", |
| .long_name = NULL_IF_CONFIG_SMALL("raw FLAC"), |
| .read_probe = flac_probe, |
| .read_header = flac_read_header, |
| .read_packet = ff_raw_read_partial_packet, |
| .read_seek = flac_seek, |
| .read_timestamp = flac_read_timestamp, |
| .flags = AVFMT_GENERIC_INDEX, |
| .extensions = "flac", |
| .raw_codec_id = AV_CODEC_ID_FLAC, |
| .priv_data_size = sizeof(FLACDecContext), |
| .priv_class = &flac_demuxer_class, |
| }; |
