The fourth chapter discusses the huffman coding method , anticipating coding method and wavelet transform coding method used in this paper 第四章討論了課題中采用的霍夫曼編碼、預測編碼和小波變換編碼的理論和方法。
Frequently used major coding methods include predical code , transform code , vectol quantization , wavelet transform code , fractal code , ect 常見的主要編碼方法有預測編碼、變換編碼、矢量量化編碼、小波編碼、分形編碼等等。
But there is obvious " block noise " in this transform coding method useing dct . and it is difficult to improve the compression performance 然而利用dct作為主要技術的變換編碼方法存在著明顯的方塊效應,而且進一步提高壓縮性能很困難。
But be careful . as our example demonstrates , it is very easy to introduce bugs by transforming code in this way , whether it is altered by human hands or by software 但是請注意:就象我們的示例所演示的那樣,以這種方式轉換代碼時很容易引入錯誤,不論是由人工還是由軟件來完成這種轉換。
In the second part : the emphasis of this part lies in discussing subband coding , wavelet transform coding and fractal coding , whose coding functions are better than the coding of having dct as the core 因此本文第二部分重點討論了編碼性能要優(yōu)于離散余弦編碼的子帶編碼、小波變換編碼和分形編碼。
Transform coding is a type of data compression for "natural" data like audio signals or photographic images. The transformation is typically lossy, resulting in a lower quality copy of the original input.