Adaptive subsampling for image data compression
Won-Yong Chong · 2002
Describes a two-to-one subsampler which allows an image to be transmitted in a layered format. Subsampling can be made adaptive to local activities of the image by using gradient measurements. Simulation results show that, for a typical outdoor scene, the picture quality in terms of the PSNR ranges from about 50 dB at 10% to 30 dB at 95% of the blocks of the image being subsampled. The DCT coefficients of the low-pass subsampled output remain highly compacted, so that further data reduction is possible.>