[Ffmpeg-cvslog] r6231 - trunk/libavcodec/vp56.c

[Michael Niedermayer]

Hi

On Tue, Sep 12, 2006 at 02:11:40PM +0200, Aurelien Jacobs wrote:
> On Tue, 12 Sep 2006 09:42:26 +0200
> Luca Barbato <lu_zero at gentoo.org> wrote:
> 
> > Guillaume POIRIER wrote:
> > > Hi,
> > > 
> > > On 9/12/06, aurel <subversion at mplayerhq.hu> wrote:
> > > 
> > > 
> > >> don't use dsp.put_pixels_tab[0][0] with unaligned ptr (fix artifacts
> > >> on altivec)
> > > 
> > > Isn't there a way to make sure the arrays passed to put_pixelsXY are
> > > aligned?
> > > Even though the MMX version of put_pixel doesn't care, it would still
> > > be faster...
> > > 
> > > As a side note, I imagine this has been discussed in another thread,
> > > but it's not so easy to find where because there's no link to it in
> > > the commit msg. :-P
> > > 
> > > Guillaume
> > 
> > The problem is the stride that isn't 16 multiple
> 
> I don't think so.
> stride here is the linesize field from the AVFrame so I expect it to be
> 16 multiple. Note that this stride can then be negated. Could that be
> the problem ?
> 
> > put_pixel should handle unaligned load just fine.
> 
> Well, the src pointer is unaligned and we can't change this as it points
> to a random pixel in the reference frame.
> I thought that's what caused trouble with altivec isn't it ?

the src pointer shouldnt have to be aligned, put_pixels is used by other
codecs with unaligned src

[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

In the past you could go to a library and read, borrow or copy any book
Today you'd get arrested for mere telling someone where the library is