DEVICE AND METHOD FOR SCALABLY ENCODING AND DECODING AN IMAGE DATA STREAM, A SIGNAL, COMPUTER PROGRAM AND AN ADAPTATION MODULE FOR A CORRESPONDING IMAGE QUALITY

A method is provided for encoding a sequence of images generating a data stream in the form of a structure of embedded data layers of n successive levels each of which corresponds to the predetermined resolution of said images. Said method comprises an encoding stage, which encodes at least one of said layers of an n+1 level by prediction on the basis of said level n layer and encodes each data layer of the level n in the form of a base sub-stream and, optionally, in the form of at least one enhancement sub-stream enabling to obtain at least one version of the enhanced quality of said images. The method also encodes, for at least one data layer of the n level, at least one single sub-stream enabling to reconstruct the version of said images at said level n resolution with a quality higher than said enhanced qualities, wherein said single sub-steam of the level n layer is not used during the prediction encoding of the layers of a level other than the level n.