[FFmpeg-devel] [PATCH] probetest.c
Mon Sep 14 18:11:20 CEST 2009
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 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?
And there is another get_le32(pb) != 0xC in vc1t_read_header you could
add to probe if still necessary...
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