oysteikt/mpd
0
0
Fork 0
Code Issues Pull Requests Releases Activity

decoder/opus: add API docs

Browse Source
This commit is contained in:
Max Kellermann 2020-07-01 20:51:44 +02:00
parent 760238fe16
commit 5ca137c73c
1 changed files with 20 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

21
src/decoder/plugins/OpusDecoderPlugin.cxx
View File

@ -75,7 +75,18 @@ class MPDOpusDecoder final : public OggDecoder {
OpusDecoder *opus_decoder = nullptr;
opus_int16 *output_buffer = nullptr;
unsigned pre_skip, skip;
/**
* The pre-skip value from the Opus header. Initialized by
* OnOggBeginning().
*/
unsigned pre_skip;
/**
* The number of decoded samples which shall be skipped. At
* the beginning of the file, this gets set to #pre_skip (by
* OnOggBeginning()), and may also be set while seeking.
*/
unsigned skip;
/**
* If non-zero, then a previous Opus stream has been found
@ -240,6 +251,7 @@ MPDOpusDecoder::HandleAudio(const ogg_packet &packet)
opus_strerror(nframes));
if (nframes > 0) {
/* apply the "skip" value */
if (skip >= (unsigned)nframes) {
skip -= nframes;
return;
@ -250,6 +262,7 @@ MPDOpusDecoder::HandleAudio(const ogg_packet &packet)
nframes -= skip;
skip = 0;
/* submit decoded samples to the DecoderClient */
const size_t nbytes = nframes * frame_size;
auto cmd = client.SubmitData(input_stream,
data, nbytes,
@ -274,6 +287,12 @@ MPDOpusDecoder::Seek(uint64_t where_frame)
try {
SeekGranulePos(where_granulepos);
/* since all frame numbers are offset by the file's
pre-skip value, we need to apply it here as well;
we could just seek to "where_frame+pre_skip" as
well, but I think by decoding those samples and
discard them, we're safer */
skip = pre_skip;
return true;
} catch (...) {