ffmpeg video filters missing

[David Liontooth]

I'd like to use the vf blackframe filter in ffmpeg, but the current 
available version does not include any filters (ffmpeg -filters shows no 
filters). In the ffmpeg documentation, it looks like filters are built 
unless they're explicitly disabled (--disable-filters), which is not 
done in the port file. Why are all the filters missing?

Cheers,
David