[M4IF Technotes] Few Queries on streaming video profile!!!
Hutter Andreas
Andreas.Hutter mchp.siemens.de
Sat Dec 1 01:59:40 EST 2001
Dear Rob, all,
sorry for my delayed reply, but I just noticed the following statement:
> > 2) does level 0 puts restriction on the size of frame to be
> > multiple of 16 ?
> > (ofcourse size should not be more that QCIF)
>
> yes.
>
> Length <= 176
> Height <= 144
> It only works in multiples of full macroblocks.
>
I believe we need to be more precise here:
To my understanding (following a discussion arising from the interop
tests)video_object_layer_width / video_object_layer_height (being the
displayable area of the VOP) do not have to be multiples of 16. However,
for the decoding process these values are automatically extended to full
macroblocks as described in clause 6.3.3. Otherwise it would not be possible
to code e.g. QSIF resolution ...
Best regards,
Andreas
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