[FFmpeg-devel] [PATCH] probetest.c

Kostya kostya.shishkov
Mon Sep 14 19:05:59 CEST 2009


On Mon, Sep 14, 2009 at 06:11:20PM +0200, Reimar D?ffinger wrote:
> On Mon, Sep 14, 2009 at 06:51:59PM +0300, Kostya wrote:
> > On Mon, Sep 14, 2009 at 05:19:03PM +0200, Michael Niedermayer wrote:
> > > Some simple probe testing code should be attached
> > > 
> > > its output, aka formats that detect random data with a score >25 are:
> > > Failure of h261 probing code with score=50 type=0 p=B53 size=2
> > > Failure of vc1test probing code with score=50 type=0 p=40E size=4
> > > Failure of h263 probing code with score=50 type=0 p=C1E size=4
> > > Failure of idcin probing code with score=50 type=0 p=E93 size=8
> > > Failure of mm probing code with score=50 type=0 p=FC0 size=128
> > > Failure of dv probing code with score=75 type=1 p=E85 size=256
> > > Failure of vmd probing code with score=50 type=0 p=AF4 size=512
> > > Failure of mpeg probing code with score=52 type=0 p=D9C size=4096
> > > Failure of dts probing code with score=51 type=1 p=B8F size=8192
> > > 
> > > maintainers of the listed formats should look into fixing their probe
> > > code!
> > 
> > Ahem, are you sure it's possible? For example, I maintain vc1test, vmd
> > and dts. First two demuxers just test 2-6 bytes and return
> > AVPROBE_SCORE_MAX / 2, for DTS you can have sync marker after some junk,
> > I suspect H.26[13] have the same troubles. If you have random-looking
> > data without clearly define header to check, you have such scores.
> 
> Well, the problem with vc1test is that it has a > 1 in 256 chance of
> recognizing random data as "good".
> Looking and the vc1t_read_header code, are you sure you haven't just
> confused && and || in the probe function?

I did, thanks for spotting.

> And there is another get_le32(pb) != 0xC in vc1t_read_header you could
> add to probe if still necessary...

I hope it is not be needed now.



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