Research On Compression Method Adopted For Panorama Image On Region Of Interest

For panorama image including a lot of information, the enhancement of image compression efficiency is taken by the drop of image quality.But according to the observers' different needs, low compression ratio or lossless compression is adopted on region of interest, and high compression ratio is taken on background, which guarantees the image quality of ROI, but also improves the compression efficiency of the whole image.Aiming at the characteristics of panorama image, the image coding method based on wavelet theory is adopted in the paper, based on the analysis of the advantages of the image coding of all kinds.The method is used to code the panorama image on ROI. First, the SPIHT algorithm based on wavelet theory is studied in the article.And then relative flexible coding controlling method is researched, in the analysis of the advantages and disadvantages of General scaling based method and Maxshift method in JPEG2000.Finally, the bit lifting on ROI is combined with SPIHT algorithm, accomplishing the image coding. The method has high compression effiency and adjustable image snr .The bit-stream could be decoded at any bit.The method proposed in the paper has flexible adjustability for the lifting bit S on ROI.Though General scaling based method in JPEG2000 could control the lifting bit S, the snr of the whole image is very low in the case of high compression ratio. Maxshift method has the same disadvantage and the lifting bit S could not be controlled.