[FFmpeg-devel] [PATCH] avcodec/version: Postpone FF_API_DEBUG_MV

[Ronald S. Bultje]

Hi,

On Sun, Oct 22, 2017 at 9:43 AM, James Almer <jamrial at gmail.com> wrote:

> On 10/22/2017 8:26 AM, Ronald S. Bultje wrote:
> > Hi,
> >
> > On Sat, Oct 21, 2017 at 9:23 PM, Michael Niedermayer
> <michael at niedermayer.cc
> >> wrote:
> >
> >> On Sat, Oct 21, 2017 at 08:52:26PM -0400, Ronald S. Bultje wrote:
> >>> Hi,
> >>>
> >>> On Sat, Oct 21, 2017 at 8:37 PM, Michael Niedermayer
> >> <michael at niedermayer.cc
> >>>> wrote:
> >>>
> >>>> This is different from FF_API_VISMV which is supported through
> >> codecview.
> >>>>
> >>>> Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
> >>>> ---
> >>>>  libavcodec/version.h | 2 +-
> >>>>  1 file changed, 1 insertion(+), 1 deletion(-)
> >>>>
> >>>> diff --git a/libavcodec/version.h b/libavcodec/version.h
> >>>> index 8584bb7006..25696690d7 100644
> >>>> --- a/libavcodec/version.h
> >>>> +++ b/libavcodec/version.h
> >>>> @@ -79,7 +79,7 @@
> >>>>  #define FF_API_SET_DIMENSIONS    (LIBAVCODEC_VERSION_MAJOR < 58)
> >>>>  #endif
> >>>>  #ifndef FF_API_DEBUG_MV
> >>>> -#define FF_API_DEBUG_MV          (LIBAVCODEC_VERSION_MAJOR < 58)
> >>>> +#define FF_API_DEBUG_MV          (LIBAVCODEC_VERSION_MAJOR < 59)
> >>>>  #endif
> >>>>
> >>>
> >>> Can you give an explanation for why this should be delayed? (It's
> missing
> >>> in the commit message, and this is hard to evaluate without a
> >>> justification/explanation.)
> >>
> >> It was not agreed on ffmpeg-devel to remove this feature.
> >>
> >> Its used for example by me occasionally to analyze videos in bug
> >> reports for debuging them.
> >>
> >> There is no replacement or alternative iam aware of
> >>
> >
> > The replacement will never be written if:
> > a) nobody cares; AND
> > b) we keep delaying the removal
> >
> > I'm considering veto'ing this patch.
>
> Personally I'm with Clement in this. The deprecation was poorly handled,
> and the feature currently has no replacement. Michael uses it for
> debugging, so removing it does not seem productive.
>
> But, also agreeing with Clement, this should absolutely be ported to the
> codecview filter before the next bump, or it will be removed.
>

But this is the whole problem. We're stuck in a stalemate between nothing
and nobody. As with ffserver, we'll keep postponing this forever more until
the stalemate is broken.

What incentive is there for anyone to write a replacement for this feature?
And stack that incentive against the pool of available developers that have
time and interest in this feature, and what are you left with?

Nothing.

==

We need to move away from this stalemate-driven development. "ffserver"
shows how that can work. What we could propose is to accept this patch,
based on the understanding that we also - at the same time - agree on
timeline for final, conclusive, non-veto'able removal of this feature
within half a year, either replaced with an improved version that went
through real review and is for once not a total hack, or just not replaced
with anything at all.

==

If debugging using this feature really only happens once in a blue moon,
why not debug on a release branch? I'm thinking of Kieran complaining about
how hard it is to work on mpegvideo (10-bits anyone?) and all of this is
just not helping at all...

Ronald