基于matlab的fbp滤波反投影算法-Based on the fbp matlab filter back projection algorithm

通过对投影数据进行滤波反投影从而得到图像的FBP算法，设置的滤波器可以自行更改为其他的-Through the projection data is filtered back-projection algorithm to obtain an image of the FBP, the filter settings can be changed to other self-

二维图像的投影和图像重建，直接傅里叶反变换法，先反投影后滤波，先滤波后反投影，卷积反投影(Two dimensional image projection and image reconstruction, direct Fourier inverse method, first backprojection, after filtering, first filter, back projection, convolution back projection)

小程序测试，生成butterwords滤波器并进行滤波反投影测试，用于测试matlab是否正常(program test for validation of Butterwords filter and Filter Back-projection by the Matlab)