This should fix several issues with odd dimensions inputs.
lut, vflip, pad and crop video filters also need to be checked for such
issues. It's possible sws is also affected.
dsputil_init() is deprecated and not meant to be exported.
ff_dsputil_init() is internal to libavcodec and thus can not be used.
avpriv_dsputil_init() is the version shared between libraries.
This commit fixes 3 unjustified libavfilter deprecated warnings.
The next commit will introduce a proper decimation filter to be used
along with the field matching filter. To avoid confusion with this
filter which has currently a very limited usage (and will not work
properly with the fieldmatching filter), the new decimation filter will
take the decimate name, and this filter is renamed to mpdecimate.
