3 * Copyright (c) 2001 Fabrice Bellard
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 #include "libavcodec/flac.h"
24 #include "flac_picture.h"
28 #include "vorbiscomment.h"
29 #include "replaygain.h"
31 static int flac_read_header(AVFormatContext *s)
33 int ret, metadata_last=0, metadata_type, metadata_size, found_streaminfo=0;
36 AVStream *st = avformat_new_stream(s, NULL);
38 return AVERROR(ENOMEM);
39 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
40 st->codec->codec_id = AV_CODEC_ID_FLAC;
41 st->need_parsing = AVSTREAM_PARSE_FULL_RAW;
42 /* the parameters will be extracted from the compressed bitstream */
44 /* if fLaC marker is not found, assume there is no header */
45 if (avio_rl32(s->pb) != MKTAG('f','L','a','C')) {
46 avio_seek(s->pb, -4, SEEK_CUR);
50 /* process metadata blocks */
51 while (!avio_feof(s->pb) && !metadata_last) {
52 avio_read(s->pb, header, 4);
53 flac_parse_block_header(header, &metadata_last, &metadata_type,
55 switch (metadata_type) {
56 /* allocate and read metadata block for supported types */
57 case FLAC_METADATA_TYPE_STREAMINFO:
58 case FLAC_METADATA_TYPE_CUESHEET:
59 case FLAC_METADATA_TYPE_PICTURE:
60 case FLAC_METADATA_TYPE_VORBIS_COMMENT:
61 buffer = av_mallocz(metadata_size + FF_INPUT_BUFFER_PADDING_SIZE);
63 return AVERROR(ENOMEM);
65 if (avio_read(s->pb, buffer, metadata_size) != metadata_size) {
66 RETURN_ERROR(AVERROR(EIO));
69 /* skip metadata block for unsupported types */
71 ret = avio_skip(s->pb, metadata_size);
76 if (metadata_type == FLAC_METADATA_TYPE_STREAMINFO) {
80 /* STREAMINFO can only occur once */
81 if (found_streaminfo) {
82 RETURN_ERROR(AVERROR_INVALIDDATA);
84 if (metadata_size != FLAC_STREAMINFO_SIZE) {
85 RETURN_ERROR(AVERROR_INVALIDDATA);
88 st->codec->extradata = buffer;
89 st->codec->extradata_size = metadata_size;
92 /* get sample rate and sample count from STREAMINFO header;
93 * other parameters will be extracted by the parser */
94 samplerate = AV_RB24(st->codec->extradata + 10) >> 4;
95 samples = (AV_RB64(st->codec->extradata + 13) >> 24) & ((1ULL << 36) - 1);
97 /* set time base and duration */
99 avpriv_set_pts_info(st, 64, 1, samplerate);
101 st->duration = samples;
103 } else if (metadata_type == FLAC_METADATA_TYPE_CUESHEET) {
106 const uint8_t *offset;
107 int i, chapters, track, ti;
108 if (metadata_size < 431)
109 RETURN_ERROR(AVERROR_INVALIDDATA);
110 offset = buffer + 395;
111 chapters = bytestream_get_byte(&offset) - 1;
113 RETURN_ERROR(AVERROR_INVALIDDATA);
114 for (i = 0; i < chapters; i++) {
115 if (offset + 36 - buffer > metadata_size)
116 RETURN_ERROR(AVERROR_INVALIDDATA);
117 start = bytestream_get_be64(&offset);
118 track = bytestream_get_byte(&offset);
119 bytestream_get_buffer(&offset, isrc, 12);
122 ti = bytestream_get_byte(&offset);
123 if (ti <= 0) RETURN_ERROR(AVERROR_INVALIDDATA);
125 avpriv_new_chapter(s, track, st->time_base, start, AV_NOPTS_VALUE, isrc);
128 } else if (metadata_type == FLAC_METADATA_TYPE_PICTURE) {
129 ret = ff_flac_parse_picture(s, buffer, metadata_size);
132 av_log(s, AV_LOG_ERROR, "Error parsing attached picture.\n");
136 /* STREAMINFO must be the first block */
137 if (!found_streaminfo) {
138 RETURN_ERROR(AVERROR_INVALIDDATA);
140 /* process supported blocks other than STREAMINFO */
141 if (metadata_type == FLAC_METADATA_TYPE_VORBIS_COMMENT) {
142 AVDictionaryEntry *chmask;
144 ret = ff_vorbis_comment(s, &s->metadata, buffer, metadata_size, 1);
146 av_log(s, AV_LOG_WARNING, "error parsing VorbisComment metadata\n");
147 } else if (ret > 0) {
148 s->event_flags |= AVFMT_EVENT_FLAG_METADATA_UPDATED;
151 /* parse the channels mask if present */
152 chmask = av_dict_get(s->metadata, "WAVEFORMATEXTENSIBLE_CHANNEL_MASK", NULL, 0);
154 uint64_t mask = strtol(chmask->value, NULL, 0);
155 if (!mask || mask & ~0x3ffffULL) {
156 av_log(s, AV_LOG_WARNING,
157 "Invalid value of WAVEFORMATEXTENSIBLE_CHANNEL_MASK\n");
159 st->codec->channel_layout = mask;
160 av_dict_set(&s->metadata, "WAVEFORMATEXTENSIBLE_CHANNEL_MASK", NULL, 0);
168 ret = ff_replaygain_export(st, s->metadata);
179 static int raw_flac_probe(AVProbeData *p)
181 if ((p->buf[2] & 0xF0) == 0) // blocksize code invalid
183 if ((p->buf[2] & 0x0F) == 0x0F) // sample rate code invalid
185 if ((p->buf[3] & 0xF0) >= FLAC_MAX_CHANNELS + FLAC_CHMODE_MID_SIDE << 4)
186 // channel mode invalid
188 if ((p->buf[3] & 0x06) == 0x06) // bits per sample code invalid
190 if ((p->buf[3] & 0x01) == 0x01) // reserved bit set
192 return AVPROBE_SCORE_EXTENSION / 4 + 1;
195 static int flac_probe(AVProbeData *p)
197 if ((AV_RB16(p->buf) & 0xFFFE) == 0xFFF8)
198 return raw_flac_probe(p);
199 if (p->buf_size < 4 || memcmp(p->buf, "fLaC", 4))
201 return AVPROBE_SCORE_EXTENSION;
204 static av_unused int64_t flac_read_timestamp(AVFormatContext *s, int stream_index,
205 int64_t *ppos, int64_t pos_limit)
207 AVPacket pkt, out_pkt;
208 AVStream *st = s->streams[stream_index];
209 AVCodecParserContext *parser;
211 int64_t pts = AV_NOPTS_VALUE;
213 if (avio_seek(s->pb, *ppos, SEEK_SET) < 0)
214 return AV_NOPTS_VALUE;
216 av_init_packet(&pkt);
217 parser = av_parser_init(st->codec->codec_id);
219 return AV_NOPTS_VALUE;
221 parser->flags |= PARSER_FLAG_USE_CODEC_TS;
224 ret = ff_raw_read_partial_packet(s, &pkt);
226 if (ret == AVERROR(EAGAIN))
231 av_init_packet(&out_pkt);
232 ret = av_parser_parse2(parser, st->codec,
233 &out_pkt.data, &out_pkt.size, pkt.data, pkt.size,
234 pkt.pts, pkt.dts, *ppos);
236 av_free_packet(&pkt);
238 int size = out_pkt.size;
239 if (parser->pts != AV_NOPTS_VALUE){
240 // seeking may not have started from beginning of a frame
241 // calculate frame start position from next frame backwards
242 *ppos = parser->next_frame_offset - size;
248 av_parser_close(parser);
252 AVInputFormat ff_flac_demuxer = {
254 .long_name = NULL_IF_CONFIG_SMALL("raw FLAC"),
255 .read_probe = flac_probe,
256 .read_header = flac_read_header,
257 .read_packet = ff_raw_read_partial_packet,
258 .read_timestamp = flac_read_timestamp,
259 .flags = AVFMT_GENERIC_INDEX,
260 .extensions = "flac",
261 .raw_codec_id = AV_CODEC_ID_FLAC,