Method for decoding a data stream that is representative of at least one image or a sequence of at least one image, an image being formed from blocks of pixels grouped into groups of predefined size, said method implementing the following steps, for at least one group of coded blocks in said data stream (F, 4000): - extracting at least one item of information on partitioning of said group, said item of information being present in said data stream and defining a border, within said group, separating, in said group of blocks, what are called exterior blocks from blocks forming at least one cluster, a cluster being formed of blocks of said group having at least one similar characteristic parameter, an exterior block belonging to no cluster of said group, said characteristic parameter belonging to the group comprising: - a value of type of predictive coding; - a movement vector value; - a zero prediction residue value; - a value of type of transform; - an illumination compensation coefficient value; and - a value of a coefficient of weighting of various predictions; - decoding the blocks forming at least one cluster of said group on the basis of cluster coding information present in said data stream, this comprising: - a step of decoding a block of said cluster, implementing a decoding of said characteristic parameter or parameters encoded only once for said cluster; and - a step of decoding the other blocks of said cluster, taking into account said previously decoded characteristic parameter or parameters; and - decoding the exterior blocks on the basis of exterior block coding information present in said data stream, taking into account at least one characteristic parameter of the previously decoded neighbouring blocks. - extracting at least one item of information on partitioning of said group, said item of information being present in said data stream and defining a border, within said group, separating, in said group of blocks, what are called exterior blocks from blocks forming at least one cluster, a cluster being formed of blocks of said group having at least one similar characteristic parameter, an exterior block belonging to no cluster of said group, said characteristic parameter belonging to the group comprising: - a value of type of predictive coding; - a movement vector value; - a zero prediction residue value; - a value of type of transform; - an illumination compensation coefficient value; and - a value of a coefficient of weighting of various predictions; - a value of type of predictive coding; - a movement vector value; - a zero prediction residue value; - a value of type of transform; - an illumination compensation coefficient value; and - a value of a coefficient of weighting of various predictions; - decoding the blocks forming at least one cluster of said group on the basis of cluster coding information present in said data stream, this comprising: - a step of decoding a block of said cluster, implementing a decoding of said characteristic parameter or parameters encoded only once for said cluster; and - a step of decoding the other blocks of said cluster, taking into account said previously decoded characteristic parameter or parameters; and - a step of decoding a block of said cluster, implementing a decoding of said characteristic parameter or parameters encoded only once for said cluster; and - a step of decoding the other blocks of said cluster, taking into account said previously decoded characteristic parameter or parameters; and - decoding the exterior blocks on the basis of exterior block coding information present in said data stream, taking into account at least one characteristic parameter of the previously decoded neighbouring blocks.