A study on transmission of low bit-rate coded video over radio links

Reports on a new method to transmit video signals over the digital cordless telephone system. Employing a video coding system H.261, a new coding control method optimized to visual characteristics, and a method developed to prevent broad frame skipping due to burst errors particular to mobile communication systems, are proposed. Though the spatial resolution (quantization-step) and the time resolution (coding frame-rate) are in a trade-off relationship, the coding control system is developed from the view point of visually optimum frame-rate and quantization step size derived from a subjective evaluation experiment. It is also shown that visually undesirable broad frame skipping can be prevented by providing a preframe buffer in the coding system.<<ETX>>