System and method for image reconstruction
The present disclosure relates to a system, method and storage medium for generating an image. At least one processor, when executing instructions, may perform one or more of the following operations. When raw data is received, a plurality of iterations may be implemented. During each iteration, a first voxel value relating to a first voxel in an image is calculated; at least a portion of a second voxel may be continuously changed with respect to at least a portion of the first voxel value; the image may be transformed to a projection domain to generate an estimated projection based on the first voxel value and the second voxel value; a projection error may be obtained based on the estimated projection and the raw data; and the image may be corrected or updated based on the projection error.
1. A method implemented on a computing device having at least one processor and a non-transitory storage medium for image reconstruction, the method comprising:
receiving raw data relating to a subject;
generating a first image based on the raw data;
constructing a noise model that indicates a noise distribution of the first image;
generating a second image by reducing noise from the first image based on the noise model;
generating a third image by subtracting the second image from the first image, wherein the third image indicates the noise in the first image;
generating a fourth image by improving a luminance or color of at least a portion of the second image; and
generating a fifth image by combining the fourth image and the third image to add an amount of noise to the fourth image.
2. The method of claim 1 , wherein the generating the first image comprises:
performing a plurality of iterations.
3. The method of claim 2 , further comprising generating an updated image during each of the plurality of iterations.
4. The method of claim 3 , further comprising transforming the updated image to a projection domain to generate an estimated projection during each of the plurality of iterations.
5. The method of claim 1 , wherein the third image is generated based on the noise model.