Research And Implementation Of SPIHT Algorithm Based On Lifting Wavelet Transform

Image is the most important carrier among the information intercommunion in people's life, and it is the biggest media containing information. As we all know, the data quantity is very large in a digital image. If the data couldn't be compressed efficiently, it will be a great obstacle to the development of communication and multimedia technologies when high transmission speed and large memory are needed in multimedia communication system. Iniage compression technology, as crucial technology in the fields of communication and multimedia, is very important to information technology nowadays and future.Wavelet-based compression scheme has been put into practice in the areas of compression of static images and motive images as well as a key part in some international standards such as JPEG2000. The basic ideology of the wavelet-based compression scheme is multi-resolution. Analyzing the image in the different space and different frequency is the first process, then we carry coefficient coding on the sub-block. Coefficient coding is the core of wavelet-based compression scheme, and the substance of the compression is carry quantity-compression on coefficient. One image is divided into four frequency thought wavelet-transformation. However, it is still a research hotspot that how to deal with the coefficients transformed from a digital image with wavelet in a more efficient way.This paper focuses on SPIHT algorithm based on lifting wavelet transform. Simulated experimental results show that great detail information is loss when high frequency images at low bit rate are compressed, reconstructive image is blur. A new scheme using DCT(Discrete Cosine Transform), DWT(Discrete Wavelet Transform) and SPIHT algorithm is put forward and experimental results in this paper indicate the scheme can improve the quality of image reconstruction and PSNR. Then this explains that the improved scheme mentioned in this essay has got fine effect, and it makes full combination of the advantages of wavelet transformation, DCT and SPIHT algorithm so that it has formed an image compression scheme which is effective in operation and excellent in capability.