On Wed, 5 Oct 2016 10:42:13 -0700 Jon Toohill <jtoohill-at-google....@ffmpeg.org> wrote:
> On Wed, Oct 5, 2016 at 10:40 AM, Jon Toohill <jtooh...@google.com> wrote: > > > On Tue, Oct 4, 2016 at 7:19 AM, wm4 <nfx...@googlemail.com> wrote: > > > >> On Mon, 3 Oct 2016 17:45:08 -0700 > >> Jon Toohill <jtoohill-at-google....@ffmpeg.org> wrote: > >> > >> > Muxers can check AVCodecParameters.initial_padding for the > >> > encoder+decoder delay, and read the AV_PKT_DATA_SKIP_SAMPLES > >> > side data from the last packet for the encoder padding. > >> > > >> > This change also fixes the first_discard_sample calculation > >> > which erroneously included the decoder delay. Decoder delay > >> > is already accounted for in st->skip_samples. The affected > >> > FATE tests have been updated accordingly. > >> > --- > >> > libavformat/mp3dec.c | 3 ++- > >> > tests/ref/fate/audiomatch-square-mp3 | 2 +- > >> > tests/ref/fate/gapless-mp3 | 10 +++++----- > >> > 3 files changed, 8 insertions(+), 7 deletions(-) > >> > > >> > diff --git a/libavformat/mp3dec.c b/libavformat/mp3dec.c > >> > index 56c7f8c..e8b2428 100644 > >> > --- a/libavformat/mp3dec.c > >> > +++ b/libavformat/mp3dec.c > >> > @@ -239,9 +239,10 @@ static void mp3_parse_info_tag(AVFormatContext > >> *s, AVStream *st, > >> > > >> > mp3->start_pad = v>>12; > >> > mp3-> end_pad = v&4095; > >> > + st->codecpar->initial_padding = mp3->start_pad + 528 + 1; > >> > st->start_skip_samples = mp3->start_pad + 528 + 1; > >> > if (mp3->frames) { > >> > - st->first_discard_sample = -mp3->end_pad + 528 + 1 + > >> mp3->frames * (int64_t)spf; > >> > + st->first_discard_sample = -mp3->end_pad + mp3->frames * > >> (int64_t)spf; > >> > >> How does mixing these even make sense? > >> > > > > mp3enc.c already uses initial_padding for the encoder delay, and as you > > previously pointed out, mp3dec.c already uses AV_PKT_START_SKIP_SAMPLES for > > the encoder delay. I'm not attempting to solve the inconsistency in this > > patch set. > > > > err, *mp3dec.c already uses AV_PKT_DATA_SKIP_SAMPLES for the encoder > padding. Sorry for the confusion. > Not solving the inconsistency is problematic - but the worse issue is that you seem to introduce inconsistencies. In my current opinion, the packet side data and the initial_padding fields do the same (i.e. duplicated API), so only one of them can or should be used. Your patch seems to require the decoder to use them both, though. _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel