[Mp4-tech] MPEG-4 Visual conformance bitstream problem

[toshi.horie conexant.com]

I have found a problem with the motion vectors on the 
following MPEG-4 visual V1 Simple Profile short header 
conformance bitstreams:
Name        Resolution  Frames  Profile Level 
san021.m4v   352x288      99      Simple L2
san022.m4v   176x144     100      Simple L1
san023.m4v   352x288      49      Simple L2
san024.m4v   352x288     127      Simple L3
These bitstreams have have unrestricted motion vectors even though 
14496-2, section 7.6.4 says "Motion vectors are allowed to point 
outside the decoded area of a reference VOP when (and only when) 
the short video header format is not in use (i.e., when 
short_video_header is 0)."
For example, on san021.m4v on the third VOP at macroblock 110,
vop=2 MB=110 comp=0 (refx,refy)=(-5,72) horiz out of range
vop=2 MB=110 comp=2 (refx,refy)=(-5,80) horiz out of range
vop=2 MB=110 comp=4 (refx,refy)=(-3,36) horiz out of range
Best Regards,
Toshi Horie
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