[FFmpeg-devel] [PATCH] ffmpeg: raise level for message printed in case of auto-select pixel format

[Stefano Sabatini]

On date Monday 2013-07-29 21:04:00 +0200, Reimar Döffinger encoded:
> On Mon, Jul 29, 2013 at 10:18:07AM -0800, Lou Logan wrote:
> > On Mon, 29 Jul 2013 12:04:09 +0200, Hendrik Leppkes wrote:
> > 
> > > On Mon, Jul 29, 2013 at 11:50 AM, Carl Eugen Hoyos <cehoyos at ag.or.at> wrote:
> > > > Stefano Sabatini <stefasab <at> gmail.com> writes:
> > > >
> > > >> On date Monday 2013-07-29 09:36:06 +0000, Carl Eugen Hoyos encoded:
> > > >> > Stefano Sabatini <stefasab <at> gmail.com> writes:
> > > >> >
> > > >> > > Will push the change in a day.
> > > >> >
> > > >>
> > > >> > You still haven't explained why raising the level
> > > >> > of a purely informational message makes any sense.
> > > >>
> > > >> I did it extensively and repeatedly in the past thread.
> > > >
> > > > While I can't really follow you with this message,
> > > > please do not commit, this patch does no good.
> > > >
> > > 
> > > Luckily, everyone is entitled to their own opinion.
> > > 
> > > I think the patch is useful, since it warns the user about an
> > > assumption the code makes, which in quite a lot of cases may not be
> > > what the user really wants.
> > > To ensure the user sees this warning, it should also be marked as a
> > > warning, or it might be missed, resulting in questions and/or
> > > complaints later.
> > > 
> > > So IMHO, just go ahead and push.
> > > 
> > > - Hendrik
> > 
> > Agreed. After helping dozens of users with this issue, and observing
> > others spending their time to do the same, making the message more
> > likely to be seen is something that I support.
> 
> I know I am being pedantic, but what is "this issue"? Certainly
> not the fact that a format was auto-selected.
> So in principle it seems likely an even better solution would
> be to only print this message when there is reason to believe
> it might cause issues - which I think might address Carl's
> objection (in particular I guess that it clutters the output with something
> that is actually not a warning or in any way indicative of any issue).
> Not that I say I believe it worth implementation effort.

Exact, the point is that there is nothing intrinsically wrong with
yuv444 in H.264, and ffmpeg can create many outputs which can only be
played by ffmpeg.

The only difference is that there are lot of people who do that
specific conversion (RGB -> H-264) and realize the output seems
"broken" and players usually don't care giving sensible feedback why
they can't play the file.

So I agree that it would be more correct to keep the current INFO
level, on the practical side raising the log level might avoid user
reports, since it will increase the chance that people will notice the
message.

I have no strong opinion on this and will leave the choice to the
ffmpeg tool maintainer.
-- 
FFmpeg = Faithless and Frenzy Minimalistic Portable Elected Gargoyle