Fig. 5-2 Hardware verification for BRD optimized motion estimation algorithm
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6. 6 . C C o o nc n cl lu us s io i o n n a an n d d f fu u tu t u re r e w wo or r k k
6. 6 .1 1 . . C Co on nc cl lu u si s io on n
In this thesis, we proposed a bandwidth-rate-distortion (B-R-D) optimized motion estimation algorithm to maximize rate distortion efficiency while can dynamically meet the available bandwidth. Compared with JM12.2, our B-R-D design could improve the bandwidth saving up to 70% under average search range size 16 due to appropriate MB-level bandwidth allocation by our B-R-D model calculation and bandwidth budget estimation; while the bandwidth saving up to 84% with further skip design added. In addition, while coding in high motion sequence, the simulation result shows our design could save average bit rate up to 13% and increase average PSNR up to 0.1dB at the same time under low bandwidth constraint.
In summary, our design could not only achieve the same and sometimes even better performance under various bandwidth constraints, but also fully utilize bandwidth for better quality maintain. Thus our design is suitable for video application nowadays.
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6. 6 .2 2 . . F Fu ut tu u re r e w wo or rk k
We have proposed rate distortion optimized motion estimation under the available memory bandwidth constraint, while there are several issues should be analyzed to further improve the performance of the B-R-D design. We find that the bandwidth can be determined in another ways. For example, we can adopt other fast algorithms, such as three-step search [25], four-step search [26], or diamond search [27] to reduce the checking points. Another example is like “pixel truncation scheme” [28], which truncates lower bits of a coefficient during ME search, and “sub-sampling scheme” [29], which sub-sample the image to a small one for ME search. All these skills mentioned above make a trade-off between the performances and the bandwidth requirement to support more flexible design in an efficient way. This is another challenge need to study in the future.
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7. 7 . Re R ef fe er r en e nc ce e
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