- samples from mplayer ftp in the "adv" profile seem to have profile=2,

which isn't the advanced one; and indeed, using adv. profile parser fails.
Using normal parser works, and that's what is done
- attempt at taking care of stride for NORM2 bitplane decoding
- duplication of much code from msmpeg4.c; this code isn't yet used, but
goes down as far as the block layer (mainly Transform Type stuff, the
remains are wild editing without checking). Unusable yet, and lacks the AC
decoding (but a step further in bitstream parsing)
patch by anonymous

Originally committed as revision 3931 to svn://svn.ffmpeg.org/ffmpeg/trunk