1. A data encoding system comprising: an encoder for receiving input data and generating corresponding encoded output data, the encoder including: processing means for processing the input data to generate, for each input data therein, a plurality of corresponding data layers including at least one base layer and at least one enhancement layer, wherein the processing means includes encoding means for receiving the input data and generating therefrom the encoded output data, the encoding means further comprising: block selecting means for selecting one or more sub-regions of the at least one enhancement layer, wherein the selected one or more sub-regions comprise regions determined suitable for having their enhancement layer residual data implemented by way of a parameter model, further wherein non-selected sub-regions comprise unsuitable sub-regions for modelling, and model extraction means for modelling the one or more suitable sub-regions for representation thereof in the encoded output data by way of descriptive model parameters.