[FFmpeg-devel] [PATCH] Fix to prevent runaway ac3 detection by looking at the actual frame rather than the first detected frame.

[Michael Niedermayer]

On Sat, Jan 28, 2017 at 09:33:35PM +0100, Marijn Meijles wrote:
> On Sat, Jan 28, 2017 at 07:56:51PM +0100, Michael Niedermayer wrote:
> > On Sat, Jan 28, 2017 at 01:52:30PM +0100, Marijn Meijles wrote:
> > > Signed-off-by: Marijn Meijles <marijn at bitpit.net>
> > > ---
> > >  libavformat/ac3dec.c | 8 ++++----
> > >  1 file changed, 4 insertions(+), 4 deletions(-)
> > 
> > the previous mail contains a description but the patch itself lacks
> > a commit message beyond the first line, the patch should contain a
> > commit message
> > 
> 
> strange, git must have eaten it. Anyway, here is an untouched patch file from git.
> 
> Marijn

>  ac3dec.c |    8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> b0db85d47bad47ca779e1748c7f0d4e97bd32e6b  0001-Fix-to-prevent-runaway-ac3-detection-by-looking-at-t.patch
> From 27e9209c1094b24bcc45ef3ff174b80cb17db775 Mon Sep 17 00:00:00 2001
> From: Marijn Meijles <marijn at bitpit.net>
> Date: Fri, 27 Jan 2017 22:08:15 +0100
> Subject: [PATCH] Fix to prevent runaway ac3 detection by looking at the actual
>  frame rather than the first detected frame.
> 
> When detecting a swapped AC3 marker the data of the frame is swapped. However, in subsequent frames the data swapped is taken from the first frame rather than the current frame.
> 
> Signed-off-by: Marijn Meijles <marijn at bitpit.net>
> ---
>  libavformat/ac3dec.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/libavformat/ac3dec.c b/libavformat/ac3dec.c
> index 363a32e..e85b0ac 100644
> --- a/libavformat/ac3dec.c
> +++ b/libavformat/ac3dec.c
> @@ -49,8 +49,8 @@ static int ac3_eac3_probe(AVProbeData *p, enum AVCodecID expected_codec_id)
>                  buf2+=16;
>              if (buf[0] == 0x77 && buf[1] == 0x0B) {

these could be changed to buf2 too but i guess its kind of making
sense to keep them so as to count stable endianness

patch applied

thx

[...]

-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

I have often repented speaking, but never of holding my tongue.
-- Xenocrates
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