[Ffmpeg-devel] Re: [Ffmpeg-cvslog] CVS: ffmpeg/libavcodec dv.c, 1.72, 1.73

Dan Maas dmaas
Fri Feb 24 03:21:57 CET 2006

>   for(a=2; a==2 || vs_total_ac_bits < size[0]; a+=a){
>        b = blks;
>        size[0] = 0;

I could be wrong, but shouldn't that be
size[0] = (6*5)*4;
to account for the 4-bit EOB code in each block?

> Are you sure that we need this chunk of code ? My concern is -- in case
> where encoder maxes out on all QNOs being 0s -- there's very little we
> can to do salvage the situation anyway. Or did you have another idea 
> when creating this chunk of code ?

Actually I like that addition... IMHO it is better to zero out the
high frequencies rather than run out of space and get essentially
random/undefined results.

You can see this by trying to encode pure noise. Most blocks run out
of space before encoding all the coefficients, which creates some odd
visual patterns. IMHO blurring out the noise is preferable to creating
structured artifacts.


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