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mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-12-23 12:43:46 +02:00

flac demuxer: improve seeking

This commit is contained in:
Rainer Hochecker 2014-04-12 18:13:32 +02:00
parent e89f3d0ed2
commit e1fcd3a007
2 changed files with 58 additions and 0 deletions

View File

@ -489,6 +489,14 @@ static int get_best_header(FLACParseContext* fpc, const uint8_t **poutbuf,
&fpc->wrap_buf,
&fpc->wrap_buf_allocated_size);
if (fpc->pc->flags & PARSER_FLAG_USE_CODEC_TS){
if (header->fi.is_var_size)
fpc->pc->pts = header->fi.frame_or_sample_num;
else if (header->best_child)
fpc->pc->pts = header->fi.frame_or_sample_num * header->fi.blocksize;
}
fpc->best_header_valid = 0;
fpc->last_fi_valid = 1;
fpc->last_fi = header->fi;
@ -516,6 +524,11 @@ static int flac_parse(AVCodecParserContext *s, AVCodecContext *avctx,
s->duration = fi.blocksize;
if (!avctx->sample_rate)
avctx->sample_rate = fi.samplerate;
if (fpc->pc->flags & PARSER_FLAG_USE_CODEC_TS){
fpc->pc->pts = fi.frame_or_sample_num;
if (!fi.is_var_size)
fpc->pc->pts *= fi.blocksize;
}
}
*poutbuf = buf;
*poutbuf_size = buf_size;

View File

@ -162,12 +162,57 @@ static int flac_probe(AVProbeData *p)
return AVPROBE_SCORE_EXTENSION;
}
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];
int ret;
if (avio_seek(s->pb, *ppos, SEEK_SET) < 0)
return AV_NOPTS_VALUE;
av_init_packet(&pkt);
st->parser = av_parser_init(st->codec->codec_id);
if (!st->parser){
return AV_NOPTS_VALUE;
}
st->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
return AV_NOPTS_VALUE;
}
av_init_packet(&out_pkt);
ret = av_parser_parse2(st->parser, st->codec,
&out_pkt.data, &out_pkt.size, pkt.data, pkt.size,
pkt.pts, pkt.dts, *ppos);
if (out_pkt.size){
int size = out_pkt.size;
av_free_packet(&out_pkt);
if (st->parser->pts != AV_NOPTS_VALUE){
// seeking may not have started from beginning of a frame
// calculate frame start position from next frame backwards
*ppos = st->parser->next_frame_offset - size;
return st->parser->pts;
}
}
}
return AV_NOPTS_VALUE;
}
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_timestamp = flac_read_timestamp,
.flags = AVFMT_GENERIC_INDEX,
.extensions = "flac",
.raw_codec_id = AV_CODEC_ID_FLAC,