Fast segmented image coding using weakly separable bases

In segmented image coding (SIC) images are segmented and the texture of a segment is expanded as a weighted sum of polynomial base functions, orthogonal on that segment. At very low bit rates, SIC produces images of better subjective quality than standard techniques such as JPEG. The computational requirements of traditional SIC are huge since the number of operations for computing b orthogonal base functions increases faster than quadratically with b. This paper presents a new class of orthogonal bases which can be computed extremely quickly because they are weakly separable (WS). The number of operations needed for generating them grows nearly linearly with b. Typically, WS bases can be generated 8 to 30 times faster than their traditional counterparts. A coding example shows that their use does not affect subjective image quality