Patent ID: 6266447
Filing Date: 2001-07-24
Classification: H04N

Abstract:
A coding apparatus comprising:a) block forming means for forming a block of sample values of an input signal;b) coding means having a first coding mode in which the block of sample values of the input signal is coded by using data representative of a difference between prediction values and the sample values of the block, and a second coding mode in which the block of the input signal is coded without using the data representative of the difference;c) a buffer memory for temporarily storing the coded data to be read out at a predetermined transmission rate;d) comparing means for comparing a data quantity of the data representative of the difference with a data quantity of data representing the sample values; ande) selecting means for selecting the coding mode according to a level of occupancy of the coded data stored in said buffer memory and a comparison result of said comparing means, said selecting means selecting the second coding mode as a current coding mode after the first coding mode has been selected consecutively for a predetermined number of times according to the level of occupancy of the coded data stored in said buffer memory and the comparison result of said comparing means.