A video coding method considering cell losses in ATM-based networks

摘要

This paper describes a video coding method which is capable of compensating for information losses due to cell discard. The proposed method separates picture elements into two groups by using quincunx subsampling. Separated picture elements are coded severally. Picture elements in one group are called higher priority pixels and their coded data are transmitted in higher priority cells, while ones in the other called lower priority pixels and their coded data are transmitted in lower priority cells. In case of network congestion, the proposed method prevents fatal degeneration in image quality by selectively discarding lower priority cells. Furthermore we take into consideration that higher priority cells are not always free from discard. As a countermeasure against losses of higher priority cells, we examine two schemes, one of which is called intrablock prediction and the other is cyclic refreshing. Experimental results show that the proposed method effectively suppresses degradation in image quality compared with conventional coding methods.