Grayscale Compression Based on Image Gradient in Medical Image Registration
Tao Zhang · Jisuanji gongcheng · 2011
The accuracy of medical image registration based on mutual information can reach sub-pixel level,with high accuracy and good robustness.However,frequent involving a huge amount of floating-point calculation,the rate of registration is very slow and can not achieve real-time requirements of clinical use.Because the rate of mutual information is relative to the amount of gray-scales,this paper presents a method based on a nonlinear grayscale mapping method which uses the gradient information of the image.A different image is decomposited and recomposited by a wavelet.Experimental result shows the method can reduce the gray scale of a image at the premise of preserving the image details.Moreover,this algorithm reduces the registration time and maintain the accuracy of registration.