The spec I found says "16 bits".
The existing code used log2(somevalue)+1.
ffmpeg uses log2(somevalue-1)+1.
The code now uses log2(somevalue-1)+1, and this makes it work with
some sample video without breaking another sample.
Now, I'm far from certain I've got the right spec, I found it by
searching the internet, so...
https://bugzilla.gnome.org/show_bug.cgi?id=654666
GET_BITS is a macro for gst_bit_reader_get_bits_uint32, which cannot
read more than 32 bits and will fail in this case where it is called
to read 79 bits. Since we want to skip those bits, gst_bit_reader_skip
is more appropriate in this case.
