Method for realizing three-dimensional back projection by graphics processor

Abstract

The invention relates to a method for realizing three-dimensional back projection by a graphics processor, comprising the following steps: storing projection data collected by a CT (Computed Tomography) processor in a host memory; meanwhile, calculating the Hermite coefficient of each pixel point and the sampling value of a spiral weight in a CT image to be reconstructed, i.e. a target image; copying the projection data in the host memory, the Hermite coefficient of each pixel point and the sampling value of the spiral weight into the display cache of the graphics processor; carrying out texture binding to data in the display cache; carrying out three-dimensional back projection in GPU (Graphics Processing Unit) to obtain a CT reconstruction image; and copying the obtained CT reconstruction image into the host memory. By applying the method disclosed by the invention, the three-dimensional back projection is realized in the GPU, and figures are chosen by virtue of a GPU three-dimensional array storage and three-dimensional texture binding technology based on a float4 data type as the basic element of a two-dimensional parameter array, thereby avoiding the problem that the figures are slowly chosen because parameter arrays are excessive so as to cause that GPU cache utilization is low so that operation efficiency is further improved and a satisfied result is obtained.

Description

technical field [0001] The invention relates to medical image reconstruction technology, in particular to a method for realizing three-dimensional back projection by using a graphics processor. Background technique [0002] The speed of 3D reconstruction of CT images has always been a hot topic in the field of reconstruction algorithms. At present, the main bottleneck restricting the speed of 3D reconstruction is the back projection part. How to improve the calculation speed of this part from the aspects of software and hardware has always been the focus of attention. [0003] Currently, processors in mainstream computers are mainly central processing units (CPUs) and graphics processing units (GPUs). Traditionally, the GPU is only responsible for graphics rendering, while most of the processing is handed over to the CPU. As early as 2000, some people began to put part of the CPU work on the GPU to accelerate the completion of certain large-scale data parallel tasks with hi...

AI Technical Summary

Problems solved by technology

[0007] Aiming at the disadvantages that the methods in the prior art are not suitable for the reconstruction of medical CT images with higher layers or the image reconstruction speed is slow, the technical problem to be solved by the present invention is to provide a method that can significantly improve the calculation speed of back projection and adapt to more Method of Realizing 3D Back Projection Using Graphics Processor in High Level

Images