同步辐射光源具有高斯分布特性,能使生物样品重建图像呈灰度分布不均匀和对比度低的特点,同时重建图像受背景噪声影响,进而造成重建生物样品的一些细节特征难以被观察和分析。针对该问题,提出了一种基于图像重建的同步辐射CT图像对比度增强方法。首先基于滤波反投影(FBP)重建算法和联合代数迭代重建技术(SART)算法分别重建图像,得到两种重建算法的重建数值区间范围,然后将FBP的数值区间映射到SART的数值区间,最后将经过映射之后的重建图像结合内容自适应图像增强算法以提高重建图像的质量。实验结果表明,所提算法不仅能够有效消除背景中的噪声,而且提高了重建图像的对比度,能更清晰地显示出重建样品的细节。

The reconstructed images of biological samples display uneven gray distribution and low contrast, since the synchrotron radiation light source possesses Gaussian distribution characteristics. Moreover, the reconstructed images are also affected by background noise, causing difficulty in observing and analyzing various details of reconstructed images of the biological samples. In order to address this situation, a synchrotron radiation CT image contrast enhancement method, based on image reconstruction, is proposed in this paper. First, the filtered back projection (FBP) reconstruction algorithm and simultaneous algebra reconstruction technique (SART) algorithm are used to reconstruct the image respectively, and the reconstructed numerical range of the two algorithms is obtained; then, the numerical interval reconstructed by the FBP algorithm is mapped to the numerical interval reconstructed by the SART. Finally, the image reconstructed by mapping is combined with a content-adaptive image enhancement algorithm to improve the reconstructed image quality. The experimental results demonstrate that the proposed algorithm can not only effectively eliminate the background noise, but also improve the contrast of the reconstructed image; therefore, allowing for more optimal visualization of the details in the reconstructed samples.