DCT transform coding of stereo images for multimedia applications

One form of multimedia finding increasing utility in factory automation is stereo imaging. Its uses include remote operation, telepresence, and object positioning. Stereo imaging, with doubled frames, requires high data-rate collection and transmission. Image compression techniques can be utilized to reduce the transmission bandwidth and/or storage space requirements of the stereo pair. This paper develops image compression techniques specific to stereo imaging and compares the performance with nonstereo methods. Disparity compensated residual image coding exploits the redundancy between the two images in a stereo pair. Stereo residuals possess special features that can be exploited within a discrete cosine transform (DCT) image coding framework. Use of these features results in several decibels of performance enhancement across a range of scene types. This approach provides its best performance below 0.75 b/pixel bitrate for 8-b grayscale imagery and below 2 b/pixel for 24-b color imagery.