Basically this causes the data to be in IYUV format but the file has the
fourcc 'yv12'. Discussions on the lqt mailinglist brought out the fact this
is on purpose to maintain compatility with the broken quicktime4linux (from
where the old yv12 codec came).
The default for this program is to put YV12 data into a YV12 file. If brokeness
is desired then use the -k option.
Note: nothing much outside some bt8x8 capture cards support uncompressed 4:2:0
anyhow.
