Gray-scale image compression with wavelet transforms
Timothy S. Wilkinson, Martin Matthew Malarkey · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1994
The wavelet transform has recently become popular as a tool for multiresolution image decomposition. Simultaneous localization of spatial and spectral information makes the wavelet transform an excellent candidate for the decorrelation stage of an image compression algorithm. This paper describes a simple but effective method of grayscale image compression that uses the wavelet transform. Nonuniform quantizers are applied to the detail subimages of the transform. Detail subimages are then grouped by decomposition level and entropy coded. The lowest resolution image, which results from the all low-pass path through the decomposition, is uniformly quantized and coded directly. Reductions in output bit rate to those of interest to the NITF low bitrate evaluation are achieved through simple scaling of the quantizers and inclusion of run-length coding.