| Summary: | 碩士 === 國立高雄應用科技大學 === 電子與資訊工程研究所碩士班 === 93 === With the extensive application of internet and image, some new requirements on image coding, such as high compression rate, pregressive codec, and compression from lossy to lossless, are to be satisfied. These functions can be performed well by Embedded Wavelets coding. On the bases of Embedded Wavelets coding, mamy newly improved algorithms have been developed in recent years. They can illustrated by algorithms like EZW, SPIHT, SPECK etc.. They need several lists during coding process. It goes without saying this process will comsume large memory space and increase time complexity. All these perplexities however raise the hardware design and manufacture costs.
In this paper, we propose an embedded wavelet image coding algorithm based on zero-blocks and array (EBZA) structures. In comparison with other methods, this EBZA is simple to realize and has higher compression efficiency. The proposed EBZA algorithm uses an array structure to build significance map of subbands. The significance map can reduce the requirement of memory space and can simplify the process. In addition, EBZA can let the significant bits and refined bits exist in 2x2 blocks that make the arithmetic coding more efficient, It will be a benefit to increase the image compression ratio.
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