[FFmpeg-devel] [PATCH] wmapro decoder

Sascha Sommer saschasommer
Sun Sep 6 11:00:10 CEST 2009


Hi,

On Samstag, 5. September 2009, Vitor Sessak wrote:
> Sascha Sommer wrote:
> > Hi,
> >
> > On Mittwoch, 2. September 2009, Vitor Sessak wrote:
> >> Sascha Sommer wrote:
> >>> Hi,
> >>>
> >>> On Dienstag, 1. September 2009, Michael Niedermayer wrote:
> >>>> On Mon, Aug 31, 2009 at 09:55:25PM +0200, Sascha Sommer wrote:
> >>>>> Hi,
> >>>>>
> >>>>>>> +    uint32_t         frame_num;                     ///< current
> >>>>>>> frame number
> >>>>>>
> >>>>>> unused
> >>>>>
> >>>>> It is used for error output and some debugging messages. Does it
> >>>>> waste too many resources?
> >>>>
> >>>> no, but fields of structs that are unused in the decoding process
> >>>> should be documented as such IMHO
> >>>
> >>> Done.
> >>>
> >>>>>>> +            /** 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?
> >>>
> >>>> [..]
> >>>>
> >>>>> New patch attached...
> >>>>
> >>>> except above, iam ok with the patch
> >>>
> >>> Ok. Commited with the mentioned changes.
> >>>
> >>> Thanks to you and everyone else who helped me to get this code into
> >>> SVN.
> >>
> >> Great! Patch to ffmpeg.org/trunk/src/index missing ;)
> >
> > If someone wants to write an entry please wait until the
> > MAX_AUDIO_FRAMESIZE change is discussed. Without this change the code
> > will fail on many multichannel files afaik.
>
> ping?
>

The MAX_AUDIO_FRAMESIZE chang is no longer required. Any volunteers for the 
news entry?

Regards

Sascha





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