Vector-Embedded Karhunen-Loève Transform and Its Application in Orientation Adaptive Coding of Images∗

In this paper, the theory and the design of a new class of orthogonal transforms are presented. The novel transform is derived from a correlation matrix in which an arbitrary orthonormal system is embedded. By embedding an orthonormal system designed empirically, we obtain the transform that is not only adapted for perceptual information but also possess statistical property like the Karhunen-Loève transform. Our main motivation is the application in block-based adaptive transform coding of images. We show a design example of the transform, which is adapted for directionality such as edges and lines. Using this transform, we perform orientation adaptive coding. Experimental results show that image coding using the transform is effective in rate-distortion sense and subjective quality. key words: Karhunen-Lo eve transform, orientation adaptive