METHOD AND DEVICE FOR ENCODING AND DECODING AN IMAGE, IN PARTICULAR A SEQUENCES OF VIDEO IMAGES, CORRESPONDING SIGNAL AND PROGRAMME-PRODUCT

摘要

The invention concerns a method and a device for encoding and decoding a digitized image, in particular a sequence of video images. The method for encoding a digitized image using a pixel block transformation, consists in defining permutations of pixels for sizes of blocks Bj (22) : rectifying (23) the orientation of the blocks Bj is carried out according to each defined permutation; encoding (24) each of said rectified blocks Bj is simulated to calculate the rate of data stream after encoding and the distortion of the reconstructed image after encoding and decoding; one permutation is selected according to a given criterion based on the rate and the distortion, the transformation being applied to the rectified blocks depending on their selected permutation. The invention is particularly useful for improving the ratio between the rate and the distortion of the decoded video images.