1) central projection
中心投影
1.
In this paper, according to the characteristics of central projection, aerial photographs were analyzed to discuss displacement of images under tilt conditin or caused by ground undulation, based on which the principles of tilt error and projection error were summarized.
根据中心投影的特性,论述了像片在倾斜条件下所引起的像点位移和像片因地面起伏而引起的像点位移,在对其进行分析的基础上总结出倾斜误差和投影误差的规律,从而说明了不能把像片当作地形图使用。
2.
Based on the analysis of Kruppas theorem and geometric methods sufficient and necessary conditions that figure Φ is a central projection of the space affine coordinate system are put forward in this paper.
本文通过对库鲁巴定理的分析,采用几何方法得出了图形Φ为空间给定仿射坐标系中心投影的充要条件。
2) projection center
投影中心
1.
This paper proposes an iterative golden section search method based on reconstructed slices evaluation of a string to achieve precise projection center,as well as detector s rotate/tilt angle and distance from x-ray spot to rotate center.
为此,文章提出了一种基于细琴弦重建图像评估的黄金分割迭代搜索法来精确确定投影中心,还可确定射线源与旋转中心距离以及探测器安装旋转角、倾斜角等参数,实验证明了该方法的有效性。
2.
The privipal steps of constructing of diagram for perspective reversion are to find out the projection center and to locate the perspective axis at suitable position.
透视反转作图的主要步骤是找出投影中心和确定透视轴的位置。
3) center projection
中心投影法
1.
Brief discussion on drawing method of utilizing center projectionto make declined intersecting line;
用中心投影法求作截交线作图方法初探
4) Multi-center projection
多中心投影
6) perspective imagery
中心投影影像
1.
Various methods for producing orthophoto out of perspective imagery;
从中心投影影像制作正射影像的多种方法研究
补充资料:滤波反投影或卷积反投影
滤波反投影或卷积反投影
影像学术语。当代影像学设备进行影像重建的数学方法。在直接用扫描后所获得的投影轨迹剖面图反投影重建出的CT图像中,无法避免角度卷入条纹伪影(angular aliasing streaks)造成的模糊和失真。这种现象与被扫描层面的空间频率中高频信息的损失有关。使用一种精密的数学方法去除这种模糊。称为“展现”(unfolding)或去卷积(deconvolution),即在反投影前使用一种数学的“滤器”或卷积函数对原始数据进行修正,然后再进行反投影。两步数学处理过程合称为滤波(修正后)反投影或卷积(后)反投影。这种方法的优点是处理过程简单,速度快,所得图像逼真、清晰。
说明:补充资料仅用于学习参考,请勿用于其它任何用途。
参考词条