Patent ID: 6853753

Claim:
An image sequence coding method for coding input image to coded data by adaptively selectively using either intra-frame coding or inter-frame predictive coding in units of blocks as coding units, comprising: an error computing step of computing, in frame-by-frame coding of the input image, the error between decoded image obtained by decoding the coded data and the input image and the error between deteriorated image in the case of assuming the missing of data and the input image; an image quality deterioration degree estimating step of block-by-block estimating the image quality deterioration degree representing the image quality deterioration degree in the case of occurrence of error in the coded data with a certain probability on the basis of both the errors; a block coding mode control step of block-by-block controlling the coding mode to either the intra-frame coding or the inter-frame predictive coding according to the image quality deterioration degree; and a frame coding step of coding all the blocks in the pertinent frame in the controlled coding modes.