Patent ID: 7805018

Claim:
A method of processing a sequence of digital images, intended to detect a grid (SG, RG) corresponding to blocking artifacts within said sequence of digital images using a circuit suitably programmed to perform the steps of: detecting a spatial grid (SG) within a portion of the image, determining a current reference grid (RG(t)) from a current spatial grid (SG(t)) and a preceding reference grid (RG(t- 1 )), based on a row comparison between said current reference grid and said preceding reference grid, wherein a number of grid rows differing between the current spatial grid SG(t) and the preceding reference grid RG(t- 1 ) is smaller than one third a number of grid rows of the preceding reference grid RG(t- 1 ); determining corrected blocking artifacts in said current reference grid (RG(t)) based on artefacts within said current spatial grid SG(t) and artefacts within said preceding reference grid RG(t- 1 ); assigning said corrected blocking artefacts to said current reference grid RG(t); and outputting said current reference grid RG(t), wherein said grid (SG, RG) comprises sets of at least one block artefact within each row and, wherein an indicator of the current reference grid (RG(t)) is updated from the corresponding indicator of the preceding reference grid (RG(t- 1 )) and from a presence or absence of the set of at least one block artefact associated with said indicator in the corresponding row of said current spatial grid (SG(t)), said indicator (ind) being associated with a set of at least one block artefact.