Transmitting digital video signals at such a low bit-rate as 1.5 Mbps needs very efficient data compression techniques.
In this paper, two compression techniques, which reduce frame-to-frame redundancy, are studied.
Firstly, Conditional Replenishment Coding (CRC), which classifies each frame into moving and stationary areas and then transmits information only about moving area, is considered. 1.5Mbps codec based on this consideration has been simulated and the result shows good picture quality at 0.4 bit/pel.
Secondly, Motion Compensation Coding (MCC), which estimates motion vector from moving area and then exploits it for coding, is considered. Here, performances of various motion vector estimation algorithms are compared on artificial and real images. The best algorithm for coding purpose is applied to 1.5Mbps codec and the resulting system shows good picture quality at 0.3 bit/pel.
