[XviD-devel] "Generic" plugin mechanism

[Christoph Lampert]

Hi,

I noticed that my "idea" of passing a function pointer to XviD core 
is just the first part of a generic plugin system. Let me just "think
aloud": 

There could be slots within encoding, in particular _before_ and _after_ 
the main encoding step, where generic functions could be called with
access to internal encoder data. Either just one, doing everything it
wants, or several, read from a linked list, etc. 

My idea are things like prefiltering of the input image e.g. with access
to adaptive quantization information, maybe also with access to motion
data. 
A PSNR-filter would also be possible (without the codec providing extra
infrastructure), by using a pre-slot (buffering the input), and a
post-slot (calculating PSNR) together. 

Of course, such filters could become a part of XVID itself, but since
there are so many possible filters around, it might be easier to just
write a small wrapper and use a routine which is not a part of the core. 
XVID could contain a "library" of default filters, but if somebody wants
to add and test a new one... no problem. 

I would like slots for "plugins" as a part of the core, not of VfW etc,
because that way, things are more portable to non-Windows plattforms. 

What do you think? 

gruel