Enable x264 visualizations during encoding. If the x264 on your
system supports it, a new window will be opened during the en-
coding process, in which x264 will attempt to present an over-
view of how each frame gets encoded. Each block type on the vi-
sualized movie will be colored as follows:
red/pink
intra block
blue
inter block
green
skip block
yellow
B-block
This feature can be considered experimental and subject to
change. In particular, it depends on x264 being compiled with
visualizations enabled. Note that as of writing this, x264
pauses after encoding and visualizing each frame, waiting for
the user to press a key, at which point the next frame will be
encoded.