[M4IF Technotes] (video_object_layer_width / height) not a mu ltiple of 16

Robert Beattie r.beattie indigovision.com
Tue May 21 12:56:48 EDT 2002


> Well I tried that too, but the artifacts seem to exist
> even then. This is what I did:
> I allocated frame buffers to store 22 x 16 MB data
> And tried clipping the motion vectors when they
> pointed to regions beyond 241 and 256 lines.

By clipping I take it you mean you padded the data from outside the active
image area with the boundary value ? Just clipping the vectors is not really
sufficient.
> What surprises me most is that the artifacts are not
> limited to the last row of MBs but are present over
> the entire VOP.

Sound's worryingly like a proper bug rather than just a misinterpretation of
the standard. I cant think why it would get through the conformance tests
though.
Sorry I cant be more help,
Dr Rob Beattie
Indigo
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