Locally adaptive resolution method for progressive still image coding

This paper presents a still image coding scheme combining both a spatial and a spectral encoder. The first one is based on a new fast and simple nonuniform sub-sampling method adapting the resolution to the local image activity, and leading to the local texture removal. This encoder can be used as a stand-alone technique for data compression at low bit rate. To improve the image quality, the error image can be passed through a second encoder, JPEG based, but where the blocks layout is provided by the first encoder. This method constitutes a generalization of the standard JPEG, which appears as a particular case of uniform sub-sampling