[FFmpeg-devel] [PATCH 1/5] tests/fate-run: only support le format result on pixfmts

[Muhammad Faiz]

On Sun, Jan 27, 2019 at 10:53 PM Michael Niedermayer
<michael at niedermayer.cc> wrote:
>
> On Sun, Jan 27, 2019 at 04:36:15PM +0700, Muhammad Faiz wrote:
> > regardless of the actual supported formats.
> > This allows filters to support only native-endian formats,
> > and also allows consistency checks between little-endian
> > and big-endian implementation.
> >
> > This also reveals bugs on gbrap10, p010, p016 format, and
> > super2xsai filter (mismatched checksums between little-endian
> > and big-endian).
> >
> > Suggested-by: Hendrik Leppkes <h.leppkes at gmail.com>
> > Signed-off-by: Muhammad Faiz <mfcc64 at gmail.com>
> > ---
> > Old thread is here: https://ffmpeg.org/pipermail/ffmpeg-devel/2016-June/195930.html
> >
> >  tests/fate-run.sh                        |   6 +-
> >  tests/ref/fate/filter-pixfmts-copy       | 112 +++++++++++------------
> >  tests/ref/fate/filter-pixfmts-crop       | 112 +++++++++++------------
> >  tests/ref/fate/filter-pixfmts-field      | 112 +++++++++++------------
> >  tests/ref/fate/filter-pixfmts-fieldorder |  88 +++++++++---------
> >  tests/ref/fate/filter-pixfmts-hflip      | 112 +++++++++++------------
> >  tests/ref/fate/filter-pixfmts-il         | 112 +++++++++++------------
> >  tests/ref/fate/filter-pixfmts-null       | 112 +++++++++++------------
> >  tests/ref/fate/filter-pixfmts-scale      | 112 +++++++++++------------
> >  tests/ref/fate/filter-pixfmts-super2xsai |   8 +-
> >  tests/ref/fate/filter-pixfmts-swapuv     |  56 ++++++------
> >  tests/ref/fate/filter-pixfmts-transpose  |  90 +++++++++---------
> >  tests/ref/fate/filter-pixfmts-vflip      | 112 +++++++++++------------
> >  13 files changed, 573 insertions(+), 571 deletions(-)
> >
> > diff --git a/tests/fate-run.sh b/tests/fate-run.sh
> > index aece90a01d..faa4285e71 100755
> > --- a/tests/fate-run.sh
> > +++ b/tests/fate-run.sh
> > @@ -297,8 +297,10 @@ pixfmts(){
> >
> >      outertest=$test
> >      for pix_fmt in $pix_fmts; do
> > -        test=$pix_fmt
> > -        video_filter "${prefilter_chain}format=$pix_fmt,$filter=$filter_args" -pix_fmt $pix_fmt -frames:v $nframes
> > +        # force little endian format on result
> > +        pix_fmt_le=`echo $pix_fmt | sed 's/be$/le/'`
> > +        test=$pix_fmt_le
> > +        video_filter "${prefilter_chain}format=$pix_fmt,$filter=$filter_args" -pix_fmt $pix_fmt_le -frames:v $nframes
> >      done
>
> if the input to a filter is a big endian format and the output is little
> endian. Then there really isnt a gurantee that the filter will work with
> big endian data. The libavfilter core could convert before or after the filter
> as it preferrs. At least thats how i remember it from the last time i looked
> at the code.
> This also makes sense, as there are very good reasons to convert before,
> for example when doing so results in better quality or higher speed
> or fewer converts overall in multi input or multi output filters...

Of course, this can be easily fixed by adding format=$pix_fmt after
$filter=$filter_args.

>
> So if the output is always forced to LE then this may unintentionally
> remove testing a range of cases.
> also this removes testing the codepath for big endian formats after the
> convert. Or do we have remaining cases that test these ?

Do you suggest to duplicate test to output BE and LE simultaneously?

>
> I am in favor of adding more and better tests but please make sure
> no codepathes drop out of all tests. (and not just by chance of the
> format negotiation randomly picking the intended choice, which it
> very well might)