[FFmpeg-devel] [PATCH] Make h264idct.c compilation optional
Tue May 22 19:42:04 CEST 2007
On Tue, 22 May 2007 11:23:15 +0200
Panagiotis Issaris <takis.issaris at uhasselt.be> wrote:
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> Panagiotis Issaris wrote:
> > Loren Merritt wrote:
> >> On Mon, 14 May 2007, Aurelien Jacobs wrote:
> >>> Panagiotis Issaris wrote:
> >>>> The attached patch tries to make the h264idct.c compilation optional.
> >>>> Not meant for direct inclusion, as I am not sure about the correctness...
> >>>> In dsputil_init() currently , for lowres decoding, when idct_algo's
> >>>> other than FF_IDCT_INT or FF_IDCT_AUTO are selected, h264 related
> >>>> functions (ff_h264_lowres_idct_put|add_c) are being used. Are these two
> >>>> functions in fact more generic then their name implies (in fact just
> >>>> misnamed), and should they be relocated to some other common file?
> >>>> Or are they really H.264 specific functions? ... but in that case it
> >>>> seems weird that selecting f.e. FF_IDCT_VP3 or FF_IDCT_SIMPLEMMX would
> >>>> result in using these H.264 specific functions.
> >>> Patch seems ok, but I also would like to hear first what's the purpose
> >>> of ff_h264_lowres_idct_put/add_c (is it h264 only or more general ?).
> >> ff_h264_lowres_idct* are not used in h264. They're so named because
> >> they apply h264's idct algo to other codecs, when whe user requests
> >> non-standards-compliant speedups. They're not the default because they're
> >> even less precise than the other lowres idct.
> > I see; thanks for the explanation.
> > So, I could:
> > * Move both functions to dsputil.c as they are only used there.
> > * Keep them in h264idct.c, but disable their usage when H.264 decoder
> > support is not compiled in. This shouldn't break anything as in that
> > case ff_jref_idct4_put() would be used instead for lowres==1.
> > Any opinions?
> This is an updated patch of above mentioned option 2, which was what the
> patch that started this thread did.
After some thought, this solution looks ok to me.
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