Patent ID: 6847739

Claim:
Method for processing compressed image data for reducing blocking artefacts, comprising the steps: deriving from a received set of primary image data (PID) of an image containing blocking artefacts at least a first and second set of intermediate image data (IID 1 , IID 2 ) the first (IID 1 ) of which substantially containing details of said set of primary image data (PID) which are smaller than said blocking artefacts and the second (IID 2 ) of which substantially containing details of said set of primary image data (PID) which are not smaller than said blocking artefacts, so as to separate image details being smaller than said blocking artefacts from image details being not smaller than said blocking artefacts, and applying a filtering process (F 3 ) at least to said second set of intermediate image data (IID 2 ), so as to substantially reduce the amplitude of signals representing said blocking artefacts, thereby yielding a modified second set of intermediate image data (IID 2 ′) and superimposing at least said first set of intermediate image data (IID 1 ) and said modified second set of intermediate image data (IID 2 ′), thereby yielding a set of post-processed image data (PPID) containing blocking artefacts at most in a reduced form, wherein at least the step of deriving said sets of intermediate image data (IID 1 , IID 2 ) involves at least a first non-linear filtering process (F 1 ).