[FFmpeg-devel] [PATCH] libavfilter-soc: implement pad filter

vmrsss vmrsss
Tue Apr 28 12:33:32 CEST 2009

Hi Stefano,

	I am glad you resurrected this, well done. Apart lacking RGB support,  
the way I remember it is that the filter worked well, but Michael  
wanted memcpy removed in favour or direct rendering and I did not know  
how to achieve that. (Also, at the time some necessary info about the  
input stream was missing from the AVFilter structures, but this might  
not be the case now.)


PS.	Besides the padcolor option (yes, it would be nice to extract some  
of the code I had written to a colourutil.[hc]), I still think that  
some of the other options I had originally considered add flexibility  
and although not vital may still be useful, in particular:

	w / h = - N or h=-N to enlarge by N pixels

	a = r to require expansion to fit a particular aspect ratio (rather  
than size)

for instance

  	pad=w=-32:a=16/9 (enlarge width by 32 pixel and then height
		as required to yield overall aspect ratio 16/9).

  	pad=w=-32:a=-1 (enlarge width by 32 pixel and then height
		as required to keep original aspect ratio).

I suppose the first form you could write as "pad=w=-32:h=w*9/16",  
which is very pretty, how about the second?

More information about the ffmpeg-devel mailing list