[M4IF Technotes] Few Queries on streaming video profile!!!

[Rob Koenen]

Gautam,
> 1) level 0 specification is in amd 3 or amd 4, as i can infer from
> http://mpeg.telecomitalialab.com/workplan.htm 
> 	that amd 4 is not in the list.

That is because amendments got renumbered as new versions are issued.
Difficult to follow at times, but we need to live with it.
The numbers in the workplan are now relative to the 2001 edition
of MPEG-4 Visual. You are now looking at AMD2 (Simple   L0) and
AMD3 (Simple Scalable @ L0)
> 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.
MPEG-4 Simple Profile Level 0 has the following restrictions
when compared to Level 1:
 a)	The maximum frame rate shall be 15 frames per second;
 b)	The maximum f_code shall be 1;
 c)	The intra_dc_vlc_threshold shall be 0;
 d)	The maximum horizontal luminance pixel resolution shall be 176
 pels/line;
 e)	The maximum vertical luminance pixel resolution shall 
 be 144 pels/VOP;
 f)	If AC prediction is used, the following restriction 
 applies : QP value
 shall not be changed within a VOP (or within a video packet if video
 packets are used in a VOP). If AC prediction is not used, there are no
 restrictions to changing QP value.
> 3) Regarding motion estimation and compensation, does it support:
> 	a) mb_type = 2 ; that is does it support different motion vectors
> for all 4 luminance blocks within the same macroblock,

Yes
> 	b) half pel motion compensation and

yes 
> 	c) unrestricted motion compensation.

yes
Best,
Rob