[FFmpeg-devel] [PATCH] libswresample: Use channel count if channel layout is undefined

[Marcin Gorzel]

Hi Tobias,

Sounds good, thanks a lot!

Regards,

Marcin

On Thu, Jul 19, 2018 at 12:53 PM Tobias Rapp <t.rapp at noa-archive.com> wrote:

> On 18.07.2018 19:31, Marcin Gorzel wrote:
> > Rematrixing supports up to 64 channels. However, there is only a limited
> number of channel layouts defined. Since the in/out channel count is
> obtained from the channel layout, for undefined layouts (e.g. for 9, 10, 11
> channels etc.) the rematrixing fails.
> >
> > In ticket #6790 the problem has been partially addressed by applying a
> patch to swr_set_matrix() in rematrix.c:72.
> > However, a similar change must be also applied to swri_rematrix_init()
> in rematrix.c:389 and swri_rematrix_init_x86() in rematrix_init.c:36.
> > ---
> >   libswresample/rematrix.c          | 6 ++++--
> >   libswresample/x86/rematrix_init.c | 6 ++++--
> >   2 files changed, 8 insertions(+), 4 deletions(-)
> >
> > diff --git a/libswresample/rematrix.c b/libswresample/rematrix.c
> > index 8227730056..d1a0cfe7f8 100644
> > --- a/libswresample/rematrix.c
> > +++ b/libswresample/rematrix.c
> > @@ -384,8 +384,10 @@ av_cold static int auto_matrix(SwrContext *s)
> >
> >   av_cold int swri_rematrix_init(SwrContext *s){
> >       int i, j;
> > -    int nb_in  = av_get_channel_layout_nb_channels(s->in_ch_layout);
> > -    int nb_out = av_get_channel_layout_nb_channels(s->out_ch_layout);
> > +    int nb_in = (s->in.ch_count > 0) ? s->in.ch_count :
> > +        av_get_channel_layout_nb_channels(s->in_ch_layout);
> > +    int nb_out = (s->out.ch_count > 0) ? s->out.ch_count :
> > +        av_get_channel_layout_nb_channels(s->out_ch_layout);
> >
> >       s->mix_any_f = NULL;
> >
> > diff --git a/libswresample/x86/rematrix_init.c
> b/libswresample/x86/rematrix_init.c
> > index d71b41a73e..4f9c92e4ab 100644
> > --- a/libswresample/x86/rematrix_init.c
> > +++ b/libswresample/x86/rematrix_init.c
> > @@ -33,8 +33,10 @@ D(int16, sse2)
> >   av_cold int swri_rematrix_init_x86(struct SwrContext *s){
> >   #if HAVE_X86ASM
> >       int mm_flags = av_get_cpu_flags();
> > -    int nb_in  = av_get_channel_layout_nb_channels(s->in_ch_layout);
> > -    int nb_out = av_get_channel_layout_nb_channels(s->out_ch_layout);
> > +    int nb_in = (s->in.ch_count > 0) ? s->in.ch_count :
> > +        av_get_channel_layout_nb_channels(s->in_ch_layout);
> > +    int nb_out = (s->out.ch_count > 0) ? s->out.ch_count :
> > +        av_get_channel_layout_nb_channels(s->out_ch_layout);
> >       int num    = nb_in * nb_out;
> >       int i,j;
> >
> >
>
> Patch looks good to me, except that the title should be updated to
> reflect the new logic. I suggest something like "swresample: Use channel
> count for rematrix initialization if defined".
>
> If nobody objects within the next days I will amend the title, push the
> patch to master and backport the fix to release branches.
>
> Regards,
> Tobias
>
>

-- 

Marcin Gorzel |  Software Engineer |  gorzel at google.com |