[FFmpeg-devel] [PATCH 5/8] ffmdec: break infinite resync loop

[Michael Niedermayer]

On Mon, Mar 09, 2015 at 12:17:38PM +0100, Andreas Cadhalpun wrote:
> On 09.03.2015 03:13, Michael Niedermayer wrote:
> >On Mon, Mar 09, 2015 at 12:04:13AM +0100, Andreas Cadhalpun wrote:
> >>Hi,
> >>
> >>some broken files can lead to an endless resync loop, which is
> >>avoided by attached patch.
> >>
> >>Best regards,
> >>Andreas
> >
> >>  ffmdec.c |   10 +++++++++-
> >>  1 file changed, 9 insertions(+), 1 deletion(-)
> >>048852d2d9b0c25157015a4befd76323fc4b2cc6  0005-ffmdec-break-infinite-resync-loop.patch
> >> From 5682ffffa0cafbaf9339352f3147ef7c494dea47 Mon Sep 17 00:00:00 2001
> >>From: Andreas Cadhalpun <Andreas.Cadhalpun at googlemail.com>
> >>Date: Sun, 8 Mar 2015 23:29:42 +0100
> >>Subject: [PATCH 5/8] ffmdec: break infinite resync loop
> >>
> >>If resyncing leads to the same position as previously, it will again
> >>lead to a resync attempt, resulting in an infinite loop.
> >
> >iam not sure this is sufficient and loops over more than 1 resync
> >point arent possible
> >maybe its better to never allow resync to start before
> >or at the previous resync point
> 
> I don't think this is possible, but it shouldn't hurt to change the
> check to '<='. This forces the syncpoints to always increase.

i was thinking more about limiting the backward seek before resync
to the last resync position +1 if there was a previous resync
so that resync which moves forward could not end before. This would
avoid the failure and allow the demuxer to continue, or at least thats
the idea

[...]

-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

Freedom in capitalist society always remains about the same as it was in
ancient Greek republics: Freedom for slave owners. -- Vladimir Lenin
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