基于小波阈值去噪的CT图像重建

CT Image Reconstruction based on Wavelets Threshold Denoising

实际扫描过程中投影数据不可避免地受到各种噪声的干扰,进而影响了图像重建的精度。提出了一种基于小波阈值去噪的图像重建方法,首先对不同角度下的投影数据进行小波分解,并对分解后的小波系数进行阀值化去噪处理,然后经过逆小波变换得到去噪后的投影数据,再由这些去噪后的投影数据进行图像重建。实验结果表明本文的方法非常有效,与传统的重建方法相比,由去噪处理后的投影数据所重建的图像质量明显改善。

The projection data usually suffer from noise during practical scanning, which will sequentially influence the precision of image reconstruction. In this paper, an image reconstruction method based on wavelet threshold denoising is proposed. Firstly, wavelet decomposition on projection data of different views is performed and the decomposed wavelet coefficient is denoised by a threshold, then by inverse wavelet transformation, the denoised projection data is got, finally use the denoised projection data to reconstruction image. Experimental result shows that this method is very effective, compared with traditional reconstruction method, the quality of reconstructed image has been imoroved greatlv.