一种新的JPEG2000多图像片压缩率预分配算法

New Compression Ratio Pre-Dispensation Algorithm for Multi-Tiles Images in JPEG2000

针对JPEG2000协议中未提及的多图像片间压缩率预分配问题进行了详尽的分析,提出一种以图像片信息含量为依据进行压缩率预分配的实用算法,并首次引入边缘检测和预测模板来衡量图像的信息含量,且深入探讨了多种图像信息含量的评价方法.大量的实验结果表明,使用压缩率预分配算法,重建图像的视觉效果可以得到不同程度的改善和加强,均方误差(MSE)显著降低,对于目标具有区域集中性的图像尤为有效;用JPEG LS、PNG预测算法和小模板的边缘检测算子来衡量图像片的信息量具有较好的实时性和有效性,能够满足硬件要求.

The problem that JPEG2000 fails to specify how to allocate the specific compression ratio among image tiles is analyzed in detail, and a novel compression ratiopredispensation algorithm based on the information of each image tile is presented. The prediction and edge detection modules are firstly used to estimate the inner information of an image tile. Several different methods of image information measurement have also been discussed and compared. With a large number of exper iment results, it is shown that the quality of the reconstructed image has been greatly improved, and for some specific images whose object has the characteristic of precinct convergence, the result could be incredibly better than we expected. For the hardware implement of JPEG 2000, JPEGLS, PNG, the small edge detection module can meet the standard of highspeed and highperformance. 