公开(公告)号：US06333991B1

公开(公告)日：2001-12-25

申请号：US09190311

申请日：1998-11-12

申请人： Bernd Schreiber ,  Frank Kreuder

发明人： Bernd Schreiber ,  Frank Kreuder

IPC分类号： G06K900

CPC分类号： G06T5/50 ,  A61N5/10

摘要： Two analysis methods for a portal image are disclosed, one to check apparatus setup and the other to check patient positioning. The first involves preparing a reference radiation field image and a sample radiation field image from a reference image and a sample image respectively by, in order, (i) defining a threshold value and (ii) setting pixels within the respective images to a dark or a bright state if darker or brighter than the threshold value, (optionally) comparing the reference radiation field image and the sample radiation field image to determine at least one of their relative rotation, translation and scaling, subtracting one of the radiation field images from the other thereby to obtain a difference image, and inspecting the difference image to ascertain changes in the radiation field between preparation of the reference image and the sample image. The second comprising the steps of filtering at least the sample image to remove low frequency variations, selecting a region of interest (ROI) within the reference and sample images, correlating the ROI of the reference image with the ROI of the sample image, and determining the relative displacements of the reference image and the sample image.

摘要翻译： 公开了门式图像的两种分析方法，一种用于检查装置设置，另一种用于检查患者定位。 首先涉及通过以下步骤从参考图像和样本图像分别准备参考辐射场图像和样本辐射场图像：（i）定义阈值，以及（ii）将各个图像内的像素设置为暗或 如果比阈值更暗或更亮，则明亮状态（可选地）比较参考辐射场图像和样本辐射场图像以确定其相对旋转，平移和缩放中的至少一个，从其中减去一个辐射场图像 从而获得差分图像，并且检查差分图像以确定准备参考图像和样本图像之间的辐射场的变化。 第二个步骤包括以下步骤：至少过滤样本图像以去除低频变化，选择参考和样本图像内的感兴趣区域（ROI），将参考图像的ROI与样本图像的ROI相关联，以及确定 参考图像和样本图像的相对位移。