Switched Segmented Image Coding - JPEG Schemes for Progressive Image Transmission

Abstract

This chapter discusses that progressive image transmission (PIT) involves the gradual improvement in the quality of an image as more information is transmitted. In recent years, PIT has been proposed as a means of providing the user with an interpretable image as soon as possible in the specific situation where he/she is interactively interrogating an image database over a low capacity transmission channel—such as the public switched telephone network (PSTN). This allows the user to decide whether to wait for a more detailed reconstruction, or to abort the transmission. Access to large image databases—such as those emerging in the medical world—will benefit from progressive coding. The chapter describes two schemes that combine JPEG and segmented image coding (SIC) for progressive image transmission. Compared to JPEG-based progressive transmission schemes, the new schemes produce reconstructed images of better quality during all the stages of transmission, and never transmit more bits. Also, the computational complexity of the new schemes is lower than that of the SIC-only approach.