基于块的比特分配的无损图像压缩算法

A Lossless Image Compression Algorithm Based on Block Bit Allocation

为了获得最佳的无损图像压缩效果,提出一种基于块的比特分配技术(block bit allocation,BBA)的图像无损压缩算法,并采用三种数字图像模式:CT、MR和DR来评价该算法.实验结果显示,此算法对比标准LempelZiv和Huffman压缩算法能将CT图像的压缩比平均增加11%到19%,在MR图像中,平均增加12%到28%.对于DR图像,此方法比Huffman算法差9%.但是,压缩和解压缩速度会更快并且可用于在线医学图像压缩.

To achieve an optimal lossless image compression , an improved method using block bit allocation technology was proposed .Images from three digital modalities of computed tomography （ CT） ,magnetic resonance imaging （ MR） and digital radiography （ DR） were used to evaluate the technique .Preliminary results showed that this method could achieve a 11%to 19% increase in the compression ratio for CT images and a 12% to 28%increase in the compression ratio for MR images as compared to standard Lempel-Ziv and Huffman coding methods.For DR images,this method performed about 9% worse than Huffman coding .However,the compression and decompression of this method was much faster and could be implemented on -line for teleradiology application .