3 results about "Back projection" patented technology

The invention provides a lung 4D-CT image super-resolution processing method based on variational optical flow estimation. A variational optical flow model used for solving an optical flow field among different lung 4D-CT phase images is constructed; the model is solved through utilizing a fast alternating direction multiplier method to acquire the optical flow field among the different phase images; based on the optical flow field, a non-local iteration back projection super-resolution reconstruction algorithm is utilized to realize reconstruction of the high resolution lung images. The method is advantaged in that on the condition that the image texture structure is enhanced, image contours can be better preserved; the main factor which influences the super-resolution reconstruction algorithm effect is image registration precision, the combined local and global CLG variational optical flow estimation model is utilized to acquire the more precise and dense optical flow field, and the fast alternating direction multiplier method is further employed to realize fast solution of the optical flow model; secondly, the non-local iteration back projection algorithm based on an edge is employed, so edges and fine grains of the super-resolution images are effectively enhanced.

The invention relates to digital rear-projection light displayú¼presenting a protection method of the bulb of digital rear-projection light displayú¼which involves the following steps: the step of power monitor and control, which means when the standby signal is detected, the abnormal shutdown mark will be cleared and a power-forbidden signal will be sent to temporary power supply module; and the step of temporary power supply, which means when the step of power monitor and control is interrupted and the signal of main-power-off is received, the temporary power supply module will be started to power the CPU, and the abnormal shutdown mark will be cleared. In the invention, a button cell is added to the control mainboard of digital rear-projection light display, functioning as a temporary power after an abnormal shutdown, thus protecting the bulbs as well as shortening the wait time of users if unnecessary.

The invention discloses a method, a device and equipment for accelerating CT iterative reconstruction. The method comprises the following steps of constructing a mask image Mask of an object based on a positioning sheet, initializing a reconstructed image f0, calculating residual projection data delta b of the forward projection data b' and the actual measurement projection data b, based on the residual error projection data deltab, only conducting back projection on object image pixels in the mask image Mask, and acquiring a residual error reconstruction image deltaf, updating the reconstructed image f0 by using the residual reconstructed image deltaf, and iterating to obtain a reconstructed image f1, judging whether the reconstruction algorithm model meets a convergence condition or not, and if yes, outputting a reconstructed image f1, or otherwise, continuing iterative computation based on the reconstructed image f1 until the reconstruction algorithm model meets a convergence condition, and outputting a reconstructed image fn, wherein n is the number of iterations. According to the method, on the premise of not additionally introducing hardware equipment and not reducing the image quality, the process of reconstructing the CT image by using an iterative reconstruction algorithm is accelerated by accelerating the process of back projection operation.