[FFmpeg-devel] [PATCH] lavfi: port mp test source

[Stefano Sabatini]

On date Tuesday 2011-08-09 21:51:50 +0200, Michael Niedermayer encoded:
> On Tue, Aug 09, 2011 at 08:59:53PM +0200, Stefano Sabatini wrote:
> > On date Tuesday 2011-08-09 16:09:47 +0200, Michael Niedermayer encoded:
> > > On Mon, Aug 08, 2011 at 02:43:15PM +0200, Stefano Sabatini wrote:
> > > > ---
> > > >  doc/filters.texi             |   57 ++++++
> > > >  libavfilter/Makefile         |    1 +
> > > >  libavfilter/allfilters.c     |    1 +
> > > >  libavfilter/vsrc_mptestsrc.c |  392 ++++++++++++++++++++++++++++++++++++++++++
> > > >  4 files changed, 451 insertions(+), 0 deletions(-)
> > > >  create mode 100644 libavfilter/vsrc_mptestsrc.c
> > > 
> > > if it produces same output
> > > then ok
> > 
> > After some comparation with showinfo, I had to change M_PI in my code
> > with 3.141592654, at this point they issue the same output but with
> > some behavior difference, for mp=test frames with number frame%30 are
> > skipped, with mptestsrc they are not (which looks more correct).
> 
> the filter was used to reverse engeneer 8x8 dct based codecs and the
> all black frames can be used to quickly spot where the different
> parts of the test patterns start

I used showinfo for that ;-). Anyway how should look the sequence?

How about
TEST1 TEST1 ... TEST1 BLACK TEST2 ... TEST2 BLACK ...
?

Consider also that I'm adding the possibility to run separately each
single test, in that case having a separation frame is pointless.
 
> > mp=test tests offset ranges from 1 to 30, for mptestsrc it is from 0
> > to 29.
> > 
> > Apart from that, the output with the same parameters is exactly the
> > same with both sources. Are you fine with this?
> >
> 
> 
> > Should I use the vf_test.c 3.141592654 constant or prefer the more
> > exact M_PI? (this will change the output)
> 
> definitly the more exact one
> 
> 
> > 
> > Let me also know if it is ok to relicense GPL -> LGPL, and if I can
> > remove the corresponding mp=test code once I commit this.
> 
> you can remove the corresponding mp=test code

> about LGPL, do you see a use case in a commercial application ?

I suppose you can find a commercial application for almost anything,
but I don't think anyone is going to ask/pay for relicensing
mptestsrc. Anyway your choice.

> The original use case was reverse engeneering closed source codecs
-- 
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