[FFmpeg-devel] Why is writing the colr atom not the default in the mov muxer?

[Michael Niedermayer]

On Tue, Feb 24, 2015 at 08:00:07AM +0000, tim nicholson wrote:
> On 21/02/15 01:34, Dave Rice wrote:
> > Hi Robert, Kevin,
> > 
> >> On Feb 20, 2015, at 9:56 AM, Robert Krüger <krueger at lesspain.de> wrote:
> >>
> >> Am Freitag, 20. Februar 2015 schrieb Kevin Wheatley :
> >>
> >>> On Fri, Feb 20, 2015 at 1:30 PM, Robert Krüger <krueger at lesspain.de
> >>> <javascript:;>> wrote:
> >>>> if I read the code correctly, the colr atom is only written in the mov
> >>>> muxer if the flag write_colr is specified. Was that behaviour chosen to
> >>>> have better backward compatibility or is there another reason not to
> >>> write
> >>>> this standard atom by default?
> >>>
> >>> I chose that way to preserve the older behaviour, as it can change how
> >>> files will be interpreted.
> >>>
> >>> I assumed that but isn't the change then a change for the better (then
> >> maybe requiring a version bump and an entry in the release notes)? After
> >> all Apple muxers write it by default as well and not trusting the input
> >> metadata seems to me like something that should be opt-out rather than
> >> opt-in but that's just my 2c.
> > 
> > That's also my two cents and I also wondered why users have to opt-in to a correctly written file. The QuickTime spec says that colr is required with some streams (such as raw uyvy422 and v210), see: https://developer.apple.com/library/mac/technotes/tn2162/_index.html#//apple_ref/doc/uid/DTS40013070-CH1-TNTAG9.
> > 
> > I'd propose that colr be written by default. The interpretation may be different but, since a file with a colr atom is more self-descriptive, the interpretation is more likely to be correct.
> 
> +1

if someone posts a patch, ill apply it

[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

You can kill me, but you cannot change the truth.
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