Worst case H.264 CABAC testing

Hi,
I want to test a H.264 CABAC decoding engine for the worst-case.
Is there any bitstream available that I can use for testing the worst
case scenerio? I know that it would be very difficult to get the worst
case bitstream, but still worth asking for. Also, is there any
bitstream which may not be for the worst case bitstream, but still
very computationally extensive to decode using CABAC?
Alternatively, is there any technqiue using which I can analyze if a
specific CABAC decoder can achieve required throughput in the worst
case.
I was thinking of using random totally bitstream to get maximum
uncorrelation, encode that bitstream, and try decoding it with CABAC
decoder. Any ideas if such scheme has already been employed and any
sound results for such schemes?
Any other tips related to CABAC testing, not necessarily related to
worst case testing, would be really helpful.
Thanks,
Sharjeel Saeed

Also, H.264 searches for patterns to later encode as vectors. The
common one is the hexagonal search or the variable hex search, so if
you got animation that avoids any pattern that can be detected
linearly (such as the video in the link) then there's your worst case
scenario.


I have a question: Using such video, would the motion vectors be
quite large in size or would the next frame be also coded as intra.
And that leads to my 2nd question: Is it possible that two successive
frames (frame i and frame i+1) are both I-Pictures?
Also, encoding of motion vectors might be helpful in case of overall
compression achieved by H.264 for a given video.
However, In my case, I am concerned about testing for worst case
CABAC performance only and not for complete H.264. Shouldn't decoding
of an Intra frame provide me with a better worst case estimate (i.e.
without motion vectors)? Decoding of even a single Intra frame should
give me an idea if the computational power of my resources is enough
or not. Am I correct in thinking that way or am I missing something?
Thanks,
Sharjeel Saeed