avfilter: replaygain scanner

Signed-off-by: Paul B Mahol <onemda@gmail.com>
avformat/bintext: protect against potential overflow of chars_per_frame

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
h263dec: use init_get_bits8() and check its return code

Fixes null pointer dereference

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