MAINTAINERS: Add my GPG fingerprint
pngdec: do not release buffer on failure instead report full progress

Should fix heap-use-after-free as reported by Address Sanitizer.

Signed-off-by: Paul B Mahol <onemda@gmail.com>
snowenc: change a bunch of assert() to av_assert()

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
mpeg4videodec: fix GEOV/GEOX fliping

Fixes Ticket317
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>