[FFmpeg-devel] [PATCH] wmapro decoder

[Sascha Sommer]

Hi,

On Sonntag, 6. September 2009, Michael Niedermayer wrote:
> On Sat, Sep 05, 2009 at 05:21:48PM +0200, Sascha Sommer wrote:
> > Hi,
> >
> > > > > > > > +            /** save transmitted scale factors so that they
> > > > > > > > can be reused for +                the next subframe */
> > > > > > > > +            memcpy(s->channel[c].saved_scale_factors,
> > > > > > > > +                   s->channel[c].scale_factors, s->num_bands
> > > > > > > > * +                  
> > > > > > > > sizeof(*s->channel[c].saved_scale_factors));
> > > > > > >
> > > > > > > what happens with s->channel[c].scale_factors so that it cant
> > > > > > > just be used?
> > > > > >
> > > > > > The saved scale factors might be resampled for several subframes
> > > > > > before some new values are transmitted and saved_scale_factors is
> > > > > > updated. If the resampled scale factors would be used for the
> > > > > > resampling, the output would change. Therefore two buffers are
> > > > > > needed.
> > > > >
> > > > > understood, please document this though, also isnt it possible to
> > > > > just exchange 2 pointers instead of a memcpy?
> > > >
> > > > I documented it. Is the attached pointer exchange code ok or did you
> > > > have something different in mind?
> > >
> > > [...]
> > >
> > > >              } else {
> > > >                  int i;
> > > > +                memcpy(s->channel[c].scale_factors,
> > > > +                       s->channel[c].resampled_scale_factors,
> > > > s->num_bands * +
> > > > sizeof(*s->channel[c].saved_scale_factors)); /** run level decode
> > > > differences to the resampled factors */ for (i = 0; i < s->num_bands;
> > > > i++) {
> > > >                      int idx;
> > >
> > > thats still a memcpy ...
> > >
> > > i had in mind, no mempcpy at all, am i missing something tha makes that
> > > impossible?
> >
> > No. Attached patch should do.
>
> ok

Applied.

Regards

Sascha