mirror of https://github.com/FFmpeg/FFmpeg.git
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
342 lines
12 KiB
342 lines
12 KiB
/* |
|
* 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 { |
|
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(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(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, out_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 (;;){ |
|
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_init_packet(&out_pkt); |
|
av_parser_parse2(parser, st->internal->avctx, |
|
&out_pkt.data, &out_pkt.size, pkt.data, pkt.size, |
|
pkt.pts, pkt.dts, *ppos); |
|
|
|
av_packet_unref(&pkt); |
|
if (out_pkt.size){ |
|
int size = out_pkt.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; |
|
} |
|
|
|
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), |
|
};
|
|
|