Allow different interpolation to VideoFrame.reformat

Created by: legraphista

Overview

There is no way to scale a video frame with other interpolation methods. SWS_BILINEAR is the best fit as a default, but for speed you would want SWS_FAST_BILINEAR, and SWS_POINT(neighbor) for up-scaling small frames (64x64) to better visualize them and keeping the information clean.

Using OpenCV would be an option but there are too many hoops to jump through. It's way faster to do in the native libav API.

Desired Behavior

Ability to use different interpolation for resizing a video frame. Right now it's hardcoded to use SWS_BILINEAR

Example API

frame.reformat(width=width,
               height=height,
               interpolation='neighbor')
# or maybe even better
frame.reformat(width=width,
               height=height,
               interpolation=av.video.interpolation.NEIGHBOR)

Additional context

Location of hardcoded flags: https://github.com/mikeboers/PyAV/blob/ae64e1ba52bea3cb72cfec473233f5137d0c1bda/av/video/frame.pyx#L200-L212