This also switches to using a separate AVCodecContext for the inner mjpeg decoder
which is cleaner and avoids fields from being overwritten with wrong values
Fixes Ticket162
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
The special cases in demuxers and decoders are a mess otherwise (and more
would be needed to support it fully)
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>