[FFmpeg-devel] [PATCH] avformat/mov: remove hack breaking creation time parsing

[Michael Niedermayer]

On Sun, Apr 09, 2023 at 03:49:33PM +0200, Marton Balint wrote:
> 
> 
> On Sat, 8 Apr 2023, Michael Niedermayer wrote:
> 
> > On Sat, Apr 08, 2023 at 08:37:24PM +0200, Marton Balint wrote:
> > > Commit 23eeffcd48a15e73fb2649b712870b6d101c5471 added a hack to support invalid
> > > files where the creation date was encoded as a classic unix timestamp. This
> > > broke however valid files having creation dates before the unix epoch.
> > > 
> > > Signed-off-by: Marton Balint <cus at passwd.hu>
> > > ---
> > >  libavformat/mov.c | 3 +--
> > >  1 file changed, 1 insertion(+), 2 deletions(-)
> > 
> > This results in:
> > @@ -1,11 +1,11 @@
> > -    creation_time   : 2012-06-20T20:58:31.000000Z
> > -      creation_time   : 2012-06-20T20:58:31.000000Z
> > -      creation_time   : 2012-06-20T20:58:31.000000Z
> > +    creation_time   : 1946-06-20T20:58:31.000000Z
> > +      creation_time   : 1946-06-20T20:58:31.000000Z
> > +      creation_time   : 1946-06-20T20:58:31.000000Z
> > 
> > Are you sure that 1946 is the correct creation date and not 2012 ?
> 
> If you are referring to the file in ticket #1471, yes, 1946 is consistent
> with what mediainfo shows for creation time. Obviously 1946 was not the
> intended creation time, but that does not warrant us to break files where
> 1946 is the *intended* creation time. Proper way to fix the original issue
> would be to detect the device and software version which produces the
> invalid files, and only apply the hack there. But I don't think that is
> doable here, the file does not seem to contain any device or software
> information.

what do you mean by intended creation time?
the file format did not exist in 1946. and all the codecs also didnt exist
so when you encounter a file that says its from that time it must be crafted
later and backdated or that bug.
we know the bug is a real thing
do you want to support crafted and backdatred files? if so can you explain
the usecase for that ?
maybe iam missing something

thx

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

Does the universe only have a finite lifespan? No, its going to go on
forever, its just that you wont like living in it. -- Hiranya Peiri
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