Annex 5 to AVC-553R

Report of the small group work to sort out the discrepancies in proposed solutions for the spatial scalable syntax
(by Mr. Ali Tabatabai)

In our small group meeting, we addressed the following two issues:

1) Dummy motion vector

Two solutions were suggested to deal with dummy motion vector.

First solution is by Japan (AVC-518).  In this solution, a new entry in frame_motion_type Table is defined with assigned code word of "00".  This code was previously identified as "reserved" code.  We feel the use of this code word may increase the potential of start_code word emulation.  

The proposal outlined in BT contribution (AVC-540) is based on macroblock_ype VLC Table expansion.  This solution may have an impact on hardware complexity, because of using longer VLC code words.

2) Full-spatial compatibility for B pictures

We recognized the need to add two new entries into the macroblock_type Table for B pictures to show "full-spatial" compatibility.  The VLC codes corresponding to these entries are listed in Doc. AVC-518, Annex 1.

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