Variable block visual pattern image coding

A variable block visual pattern image coding scheme that offers high-fidelity images, high compression ratio (29.50:1), and extremely low complexity is proposed. A set of visual patterns was designed by applying spatial constraints and considering their visual importance. A subset of the patterns may be chosen for an application. A block of pixels can be represented by either a uniform pattern or one of the edge patterns. A weighted block gradient is introduced as a criterion to judge whether an image block is roughly uniform or contains a visible edge. Image coding is simplified to coding of the pattern index and one or two related parameters.<>