[FFmpeg-devel] [PATCH] Added integer 32 bits support to wavpack
Sat May 2 14:47:13 CEST 2009
On Sat, May 02, 2009 at 12:07:42AM +0200, Laurent Aimar wrote:
> On Fri, May 01, 2009, Reimar D?ffinger wrote:
> > On Fri, May 01, 2009 at 07:39:37PM +0300, Kostya wrote:
> > > On Fri, May 01, 2009 at 06:08:37PM +0200, Laurent Aimar wrote:
> > > > > I'd use s->crc_extra = AV_RL32(buf) and open bit buffer after that but this
> > > > > looks fine too. Oh, and please add block size check.
> > > > Using the bitstream reader here seems simpler to me, and additionnaly
> > > > avoid the need of buffer size checks ;)
> > >
> > > It's not - if size <=4 (as WavPack source code says), it should be treated as
> > > error, so check is needed anyway (not for bits reading though).
> > Huh? Where does that idea that using the bitstream reader means you can
> > skip the size checks come from?
> There is a CRC anyway, but I added the check to ensure detecting error as
> soon as possible (and to avoid the possibility of a false positive CRC in this
> particuliar case).
I can't see how the CRC would avoid crashes. And actually I am not 100%
sure the committed code avoids crashes if the extrabits buffer is too
small (though it is possible it can't be too small because the
compressed data comes after it).
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