Hybrid KLT-SVD image compression

Abstract

This paper investigates a transform adaptation technique, applied to transform coding of images, as a way of exploiting the variation in local statistics within an image. The method makes use of the relationship between the Karhunen-Loeve transform (KLT) and singular value decomposition (SVD), and their energy compaction properties. We compare this approach to a standard KLT coding system. Motivated by increased coding efficiency an analysis-by-synthesis approach using switching between the KLT coding system and the hybrid KLT-SVD system is proposed. The switching is implemented using a global rate-distortion criterion. The results are encouraging and the proposed techniques provide new insights on how to use SVD in an image compression system.