公开(公告)号：US06345113B1

公开(公告)日：2002-02-05

申请号：US09228379

申请日：1999-01-12

申请人： Carl R. Crawford ,  Ibrahim M. Bechwati ,  Sergey Simanovsky ,  Muzzafer Hiraoglu

发明人： Carl R. Crawford ,  Ibrahim M. Bechwati ,  Sergey Simanovsky ,  Muzzafer Hiraoglu

IPC分类号： G06K900

CPC分类号： G06K9/00771 ,  G06K9/00201 ,  G06K2209/09

摘要： An apparatus and method for identifying and classifying objects represented in CT data for a region using the shape of the objects are disclosed. An object represented by CT data for a region is identified. Next, a two-dimensional projection of the object along a principal axis of the object is generated. The principal axis can be identified by computing eigenvectors of a covariance matrix of spatial locations of voxels in the CT data that are associated with the object. The smallest eigenvector can be selected as the principal axis of the object along which the two-dimensional projection is generated. The identification of the object can be used in the classification of the object such as by altering one or more discrimination parameters.

摘要翻译： 公开了一种用于使用对象的形状来识别和分类在用于区域的CT数据中表示的对象的装置和方法。 识别由区域的CT数据表示的对象。 接下来，生成物体沿物体的主轴的二维投影。 可以通过计算与对象相关联的CT数据中的体素的空间位置的协方差矩阵的特征向量来识别主轴。 可以选择最小的特征向量作为生成二维投影的物体的主轴。 对象的识别可以用于对象的分类，例如通过改变一个或多个辨别参数。

公开(公告)号：US06195444B1

公开(公告)日：2001-02-27

申请号：US09228380

申请日：1999-01-12

申请人： Sergey Simanovsky ,  Ibrahim M. Bechwati ,  Muzzafer Hiraoglu ,  Carl R. Crawford

发明人： Sergey Simanovsky ,  Ibrahim M. Bechwati ,  Muzzafer Hiraoglu ,  Carl R. Crawford

IPC分类号： G06K900

CPC分类号： G06K9/00771 ,  G06K2209/09

摘要： A method and apparatus for detecting concealed objects in computed tomography data are disclosed. Sheet-shaped objects such as sheet explosives can be detected by a CT scanning system, in particular, a CT baggage scanning system. The invention analyzes CT voxels in a subregion in proximity to the sheet object to determine if the sheet object is concealed in an electronic device or is “sandwiched” within an item such as a book or magazine. To detect electronic concealment, the number of voxels in a subregion that contains the object having a density above a predetermined threshold is counted and the ratio of that number of voxels to the number of object voxels is computed. If the ratio exceeds a threshold, then it is concluded that the object is concealed in electronics. In response, the CT scanning system can alter discrimination parameters to allow the object to be classified as a threat. For “sandwich” concealment, layers on opposite sides of a sheet object are examined. The mean and standard deviation of density values for the voxels are computed. Where the mean density exceeds a predetermined threshold and the standard deviation is below a different threshold, for at least one of the layers, then it is concluded that the sheet object is sandwiched within an innocuous object such as a magazine or a book.

摘要翻译： 公开了一种用于检测计算机断层摄影数据中的隐藏对象的方法和装置。 CT扫描系统，特别是CT行李扫描系统可以检测片状物体，如片状炸药。 本发明分析在片材对象附近的子区域中的CT体素，以确定片材物体是否被隐藏在电子设备中，或者被“夹在”诸如书籍或杂志的物品内。 为了检测电子隐藏，对包含密度高于预定阈值的对象的子区域中的体素数进行计数，并计算该体素数与对象体素数之比。 如果比值超过阈值，则得出结论，该物体被隐藏在电子设备中。 作为响应，CT扫描系统可以改变辨别参数以允许对象被分类为威胁。 对于“三明治”隐蔽，检查片材对象的相对侧上的层。 计算体素密度值的平均值和标准偏差。 在平均密度超过预定阈值并且标准偏差低于不同阈值的情况下，对于至少一个层，则得出结论，片材物体被夹在诸如杂志或书籍的无害物体内。