用Matlab实现的后向投影算法，一个经典的投影算法，常用语CT断层成像中-After using Matlab implementation of the algorithm to the projection, the projection of a classical algorithm, commonly used terms in CT tomography

使用了颜色直方图和后映射的方法对图像中的model进行识别。即输入model,和待分析图像，在图像中找到此model.-Use color histogram and backprojection to recognize models in the input image.