Nonuniform visual pattern image sequence coding
Peter L. Silsbee, Alan Conrad Bovik · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1991
Visual Pattern Image Sequence Coding (VPISC) is a pyramidal image coding scheme which utilizes human visual system (HVS) properties to achieve low bit rates while maintaining a good perceived image quality, all with extremely low computational cost. This paper describes extensions of VPISC, termed Foveal VPISC (FVPISC) and Adaptive VPISC (AVPISC). Both algorithms produce decreased bit rates by selectively allowing some image regions to be coded at low resolution. In FVPISC, a foveation criterion is used to select a region of interest. In AVPISC, the algorithm adaptively determines which regions require high-resolution coding in order to maintain uniform image quality over the entire image. After coding but before transmission, the encoder examines its own output, and reduced the transmission bit rate by eliminating high- resolution information about low-resolution portions of the image. The method is adaptive in the sense that the bit rate is locally adjusted to match the level of detail present in an image region.