[MPlayer-dev-eng] PATCH to support theora-exp in mplayer

[Timothy B. Terriberry]

> Flip is deprecated and must not be used anymore. Instead use negative
> strides if your codec outputs upside-down pictures.

The problem is this: the library outputs right-side up pictures, but
they are decoded from bottom to top, as this is how they are stored in
the bitstream. However, mplayer's filters (most notably vf_scale) do not
handle slice rendering unless it is done from top to bottom. So the
codec uses negative strides to flip the image, performs slice rendering
from top to bottom, and uses the flip flag to restore the image to its
proper orientation.

If you have a better suggestion, I'm all ears.