An Image Compression Algorithm Based On DCT Coefficients Rearranged By Wavelet Structure

Image compression coding includes loss compression coding and lossless compression coding. The image compressed can save space and its quality can be better. Discrete Cosine Transform (DCT) works simple and is similar to wavelet transform. It is practical to study image coding technique based on DCT.In image compression coding based on wavelet technique, embedded coding produces code streams that it can be truncated randomly. This character has application value in transmitting the images and videos. The typical representations of embedded coding are which Using Zero-Trees of wavelet coefficients (EZW) and Set Partitioning In Hierarchical Trees (SPIHT). SPIHT is a best transmission coding. It uses Spatial Orientation Tree (SOT), which effectively shows wavelet structure and improves coding efficiency. This paper introduces a embedded coding method based on the similar wavelet coefficients structure, which is said MSESPIHT. The method rearranges coefficients of 8*8 block DCT and reduces high correlation between low frequency coefficients by a mean-subtract method. Then, image is compressed by SPIHT coding with high PSNR at high compression ratios.