The HD-MAC (High Definition-Multiple Analog Components) TV system is based on the multiple sub-Nyquist sampling techniques, depending on the amount of scene motion as in other HDTV systems. The system performance is very much dependent on the methods of motion estimation and decision of sub-sampling modes.
In this thesis, the symmetrical three step BMA (block matching algorithm) is used for motion estimation of the skipped field in the 40ms sub-sampling mode. To reduce computational complexity in block matching, additional 2:1 sub-sampling is applied to the 40ms video data.
To increase the temporal correlation among the selected modes of sub-sampling after the a posteriori decision step, a modified method is investigated in the branch signal comparison.
In the a priori decision step, a sub-block based motion detection method is proposed for reduced complexity and better reliability.
Simulation results show that the sub-sampling modes after decision step have a higher temporal correlation, and that the amount of computation for a priori decision is reduced to less than one eighth of conventional method.
