[FFmpeg-devel] [PATCH] swscale: Support setting filters through AVOptions

Stefano Sabatini stefasab at gmail.com
Mon Oct 21 17:24:32 CEST 2013


On date Monday 2013-10-14 19:28:41 +0200, Stefano Sabatini encoded:
> On date Sunday 2013-10-13 20:57:40 +0200, Stefano Sabatini encoded:
[...]
> Updated and more tested, and with some docs.
> 
> I still need sane documentation telling exactly what source and
> destination filter are, and some relevant use cases/examples (I'm not
> the best person to tell).

>From what I can understand the filters are applied this way:

val(x) = (Sum_i=0:n-1 coeff(i)*val(x-n/2+i)) / n

Is this correct? Shouldn't we require that the size of the filter must
be odd?

> Also, what happens if the filter are not specified, what if the input
> is not scaled (pixel format conversion?)? Is it possible to apply the
> filters *without* rescaling?

When no rescaling and/or conversion is selected no filter is
applied. Should I file this as a bug?
-- 
FFmpeg = Forgiving Formidable Mean Philosophical Exploitable Gadget


More information about the ffmpeg-devel mailing list