Patent Document ID: 8107753
Application ID: 12863727
Patent Status: 1

Claim One:
1. A method of compressing a block of multiple pixels each having a respective property value, said method comprising the steps of: hierarchically defining a subblock in said block based on property values of a subset of said multiple pixels or of a set of hierarchically lower subblocks in said block; determining a property value for said subblock based on at least a portion of said property values of said subset of said multiple pixels or of said set of hierarchically lower subblocks; providing a prediction of said determined property value by: a) determining a first variance representation of property value(s) of at least one neighboring pixel or subblock in a first prediction direction in said block and property value(s) of at least one neighboring pixel or subblock in a second prediction direction in said block; b) determining said prediction based on a weighted combination of at least one property value of said at least one neighboring pixel or subblock in said first prediction direction and at least one property value of said at least one neighboring pixel or subblock in said second prediction direction if said first variance representation is smaller than a first variance threshold; c) selecting a prediction direction of said first and second prediction directions if said first variance representation is not smaller than said first variance threshold; d) determining said prediction to be based on at least one property value of said at least one neighboring pixels or subblocks in said selected prediction direction if said first variance representation is not smaller than said first variance threshold; e) providing a first guiding bit associated with said selected prediction direction if said first variance representation is not smaller than said first variance threshold; calculating a prediction error based on said determined property value and said provided prediction; and determining an encoded representation of said prediction error, wherein a compressed representation of said block comprises said encoded representation and said optional first guiding bit.