[FFmpeg-devel] [PATCH] Added integer 32 bits support to wavpack

Laurent Aimar fenrir
Sat May 2 20:42:41 CEST 2009

On Sat, May 02, 2009, Kostya wrote:
> On Sat, May 02, 2009 at 08:03:17PM +0200, Laurent Aimar wrote:
> > On Sat, May 02, 2009, Kostya wrote:
> > > >  I thought that the bitstream layer ensured that no read could go beyond the
> > > > provided buffer.
> > > >  Looking at get_bits.h it does not seems to, so I have attached a patch that
> > > > check that the provided buffer is wide enought.
> > > 
> > > Why not check it once during initialization? Decoder always read
> > > extra_bits*channels*samples+32, doesn't it?
> >  From wv docs, it does not seems that the order of the chunks is imposed, so
> > I cannot suppose that INT32INFO (needed to know the number of bits)
> > is received before EXTRA_BITS.
> On the second thought this check is not really needed - we may be more
> or less sure that we got right CRC so wrong bits will be catched by it.
 That's not the issue, get_bits cannot be called if the buffer is not wide
enough (at least it is my understanding).
> Checking it for each sample is an overkill IMO.
 It is not what I do, the check is done only once per input packet.

> You can always check
> that after all chunks are parsed but before real decode has started but
 It is done like that, sorry if I wasn't clear, I just meant that I had to wait
for all chunks to be parsed as I cannot check it when I received the EXTRA_BITS


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