Updated encoding notes wrt newer ffmpeg.
Updated encoding notes wrt newer ffmpeg.

pauldoo/scratch,pauldoo/scratch,pauldoo/scratch,pauldoo/scratch,pauldoo/scratch,pauldoo/scratch,pauldoo/scratch,pauldoo/scratch,pauldoo/scratch,pauldoo/scratch,pauldoo/scratch,pauldoo/scratch,pauldoo/scratch,pauldoo/scratch