[FFmpeg-devel] [PATCH]lavc/amrwbdec: Do not ignore NO_DATA frames

[Carl Eugen Hoyos]

Am So., 5. Apr. 2020 um 16:45 Uhr schrieb James Almer <jamrial at gmail.com>:
>
> On 1/30/2019 10:47 AM, Carl Eugen Hoyos wrote:
> > 2019-01-29 22:47 GMT+01:00, Carl Eugen Hoyos <ceffmpeg at gmail.com>:
> >> Hi!
> >>
> >> Attached patch fixes decoding NO_DATA amr-wb frames.
> >
> > Now with patch.
> >
> > Carl Eugen
>
> > From 0a8c318c49ec358ad646ed601588154cf7d7da37 Mon Sep 17 00:00:00 2001
> > From: Carl Eugen Hoyos <ceffmpeg at gmail.com>
> > Date: Tue, 29 Jan 2019 22:46:37 +0100
> > Subject: [PATCH] lavc/amrwbdec: Do not ignore NO_DATA frames.
> >
> > Fixes the actual output duration of the sample in ticket #7113.
> > ---
> >  libavcodec/amrwbdata.h |    2 +-
> >  libavcodec/amrwbdec.c  |    9 ++++++++-
> >  2 files changed, 9 insertions(+), 2 deletions(-)
> >
> > diff --git a/libavcodec/amrwbdata.h b/libavcodec/amrwbdata.h
> > index 8a8cbfd..95c0aaa 100644
> > --- a/libavcodec/amrwbdata.h
> > +++ b/libavcodec/amrwbdata.h
> > @@ -1884,7 +1884,7 @@ static const float lpf_7_coef[31] = { // low pass, 7kHz cutoff
> >  /** Core frame sizes in each mode */
> >  static const uint16_t cf_sizes_wb[] = {
> >      132, 177, 253, 285, 317, 365, 397, 461, 477,
> > -    40 /// SID/comfort noise frame
> > +    40, 0, 0, 0, 0, 0, 0
> >  };
> >
> >  #endif /* AVCODEC_AMRWBDATA_H */
> > diff --git a/libavcodec/amrwbdec.c b/libavcodec/amrwbdec.c
> > index 47fe7eb..b488a5d 100644
> > --- a/libavcodec/amrwbdec.c
> > +++ b/libavcodec/amrwbdec.c
> > @@ -1119,12 +1119,19 @@ static int amrwb_decode_frame(AVCodecContext *avctx, void *data,
> >      buf_out = (float *)frame->data[0];
> >
> >      header_size      = decode_mime_header(ctx, buf);
> > +    expected_fr_size = ((cf_sizes_wb[ctx->fr_cur_mode] + 7) >> 3) + 1;
> > +
> > +    if (ctx->fr_cur_mode == NO_DATA) {
> > +        for (i = 0; i < frame->nb_samples; i++)
> > +            buf_out[i] = 0.f;
>
> You can use av_samples_set_silence() for this.

(Is memset(0) valid for floats?)

Patch sent, thank you!

Carl Eugen