Patent ID: 10181207

Abstract:
Methods, devices, and apparatus, including computer programs encoded on a computer storage medium for reconstructing an image are provided. An example method includes: acquiring Computed Tomography (CT) projection data of a subject, determining an image cutoff frequency Fimg according to a CT image matrix size for reconstructing a CT image and an imaging field of view size, obtaining a convolution kernel and a cutoff frequency Fker of the convolution kernel, using the convolution kernel as a reconstruction convolution kernel when Fker<Fimg; adjusting Fker to a product of a preset value k and Fimg and truncating the convolution kernel to obtain a portion of the convolution kernel having a cutoff frequency no more than the adjusted Fker as the reconstruction convolution kernel when Fker≥Fimg, and reconstruct the CT image with the CT projection data and the reconstruction convolution kernel by using a convolution back-projection algorithm.