| In recent decades, the unprecedented development and application of digital image compression technology has been promoted by the rapid development of computer technology. Currently, digital image compression technology has been widely used in industrial, military, transportation, agriculture and other fields and has become the object of study in various disciplines. How to transmit the large image data within the limited network bandwidth become the people's increasing demand, which makes the image compression has become essential. The traditional image compression and coding method can not meet the needs of image processing. Therefore, this paper uses the popular wavelet image compression and coding methods to further improve the image compression performance.This article first briefly outlines the necessity and history of image compression, then introduces the basic theory of wavelet transform, and then focuses on two classical wavelet coding method-zero-tree coding and embedded zero-tree coding and proposes new quantization and coding scheme and the combination of Huffman coding of DPCM predictive coding based on embedded zero tree coding. Finally, the embedded zero-tree decoding methods are briefly described. Taking an example of the international standard test image, a detailed description of the research program has been proposed in this paper.This paper, based on Visual C++6.0 development platform, programmes and implements the image compression and coding system. The results of the international standard test image showed that:the improved compression algorithm proposed in this paper has the characteristics of high compression efficiency and short runtime. Comparing with the traditional compression method, the scheme can enhance the image compression ratio and also ensure the quality of the image. Therefore, the use of wavelet compression and coding is suited for the occasion of higher image compression ratio and quality requirements. |
