[FFmpeg-devel] [PATCH 8/9] x86: dct-test: add 10 bits versions.
christophe.gisquet at gmail.com
Sat Oct 10 18:14:13 CEST 2015
2015-10-10 13:20 GMT+02:00 Michael Niedermayer <michael at niedermayer.cc>:
> On Fri, Oct 09, 2015 at 11:53:45PM +0200, Christophe Gisquet wrote:
>> libavcodec/x86/dct-test.c | 13 ++++++++++++-
>> 1 file changed, 12 insertions(+), 1 deletion(-)
> with this patch
> libavcodec/dct-test -i 0 10
> end in "Error: 1." after testing SIMPLE10-C
Well, the source of the error is omse > 0.02. What a pity that
simple10-c was implemented but fails that (omse=0.03060703). The x86
implementation simply tries to be bit-exact to it, so if there's
something to fix, that's the C version first.
We can probably get one more bit of precision from it by changing the
scaling (dct-test passing with omse=0.01663750 and no change to PSNR
in dnxhd fate tests although the hashes change), but I would assume
the persons that chose those coefficients had reasons... And that
would break prores and its extra shift.
> libavcodec/dct-test 0 10
> tests IJG-LLM-INT10:which looks like it fails the test
Huh? Even on master, I don't see a IJG-LLM-INT10 being tested when I
run this command. IJG-LLM-INT is indeed ran, but fails utterly.
> the FAAN dct would pass and was tested previously but is not tested
> anymore (this was possibly caused by the previous patch not this one)
Yes it passes, and the patch should be so that this doesn't change.
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