avutil: move av_get_time_base_q() after include rational.h

Fix compilation

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
fic: Simplify alpha blending

Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
fic: Remove redundant clips

The equations can't overflow or underflow anyway.

Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
fic: Make warning message more accurate

Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
On2 AVC decoder
on2avc: change a comment at #endif to match actual define