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30 May 2000 Variable-block-size double predictor DPCM image coding
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Proceedings Volume 4067, Visual Communications and Image Processing 2000; (2000)
Event: Visual Communications and Image Processing 2000, 2000, Perth, Australia
This study is to improve double predictor differential pulse code modulation (DP-DPCM) algorithm for image data compression. A variable block-size double predictor DPCM (VBDP-DPCM) image coding system operates on an image that has been preprocessed into segments of variable size, square blocks, and each block is separately encoded by a DP-DPCM system. Quadtree segmentation algorithm is utilized to divide a given real-world image into variable size image blocks. The detail regions of a given image is segmented into blocks with smaller block size, and the background regions of the image will be assigned larger block size to the image blocks. After quadtree segmentation procedure, the differential values between the nearby pixels within an image block are reduced. Therefore, we can decrease the distribution range of the prediction error as well as reduce the quantization levels and the bit rate. We then adopt the double predictor DPCM image coding system to reduce the effect from the fed-back quantization error and not to increase the system complexity. The source coding performance of this proposed variable block-size DP-DPCM image encoder/decoder system is about 5 dB (or greater) coding gain in Signal-to-Noise Ratio than that of a conventional DPCM system.
© (2000) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Jia-Chyi Wu, Hong-Bing Chen, and Ren-Jean Liu "Variable-block-size double predictor DPCM image coding", Proc. SPIE 4067, Visual Communications and Image Processing 2000, (30 May 2000);

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