Browsing by Author "CHERN, MG"

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IMAGE COMPRESSION BY CARDINALITY DISTRIBUTION
(1994-09-01)
CHU, CH
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CHERN, MG
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HSUEH, YC
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資訊工程學系
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Department of Computer Science
Cardinality distribution is an efficient technique to display images with different gray level systems. In this paper, we extend the application of cardinality distribution to image compression. Image is first quantized to an image with fewer gray levels. Because the cardinality-distributed images possess the desired dithering patterns, the quantized images have the more compact forms. In the decompression, gray level expansion by cardinality distribution is proposed to reconstruct the images. Therefore, cardinality distribution not only has the ability to quantize images with different gray levels but also has the potential to compress images.
IMAGE REQUANTIZATION BY CARDINALITY DISTRIBUTION
(1991)
HSUEH, YC
;
CHERN, MG
;
CHU, CH
;
交大名義發表
;
資訊工程學系
This article presents a new approach to image requantization, called cardinality distribution. The new method introduces dithering patterns as ordered dither does; however, it provides a smoothing parameter p between 0 and 1. When p is chosen to be near 0.5, the new method can capture very sharp details of images. Therefore, the major deficiency of ordered dither can be avoided. Moreover, the reordering technique and its modified version are used to code bilevel and higher gray-level requantized images, respectively.