homography

问题 I'm detecting markers on images captured by my iPad. Because of that I want to calculate translations and rotations between them, I want to change change perspective on images these image, so it would look like I'm capturing them directly above markers. Right now I'm using points2D.push_back(cv::Point2f(0, 0)); points2D.push_back(cv::Point2f(50, 0)); points2D.push_back(cv::Point2f(50, 50)); points2D.push_back(cv::Point2f(0, 50)); Mat perspectiveMat = cv::getPerspectiveTransform(points2D,

问题 I'm detecting markers on images captured by my iPad. Because of that I want to calculate translations and rotations between them, I want to change change perspective on images these image, so it would look like I'm capturing them directly above markers. Right now I'm using points2D.push_back(cv::Point2f(0, 0)); points2D.push_back(cv::Point2f(50, 0)); points2D.push_back(cv::Point2f(50, 50)); points2D.push_back(cv::Point2f(0, 50)); Mat perspectiveMat = cv::getPerspectiveTransform(points2D,

问题 I'm detecting markers on images captured by my iPad. Because of that I want to calculate translations and rotations between them, I want to change change perspective on images these image, so it would look like I'm capturing them directly above markers. Right now I'm using points2D.push_back(cv::Point2f(0, 0)); points2D.push_back(cv::Point2f(50, 0)); points2D.push_back(cv::Point2f(50, 50)); points2D.push_back(cv::Point2f(0, 50)); Mat perspectiveMat = cv::getPerspectiveTransform(points2D,

问题 I want to apply homography to the following points: array([[-7.4894, 1.8873], [-7.4973, 1.8543], [-7.5375, 1.6725], [-7.5681, 1.522 ], [-7.5961, 1.371 ], [-7.6252, 1.2013], [-7.6504, 1.031 ], [-7.667 , 0.8985], [-7.6817, 0.7657], [-7.6954, 0.613 ], [-7.7054, 0.4786], [-7.7124, 0.3452], [-7.7182, 0.1931], [-7.7215, 0.0866], [-7.7716, 0.0872], [-7.7715, 0.0929], [-7.7651, 0.2884], [-7.7587, 0.4269], [-7.7528, 0.5233], [-7.7418, 0.6616], [-7.7275, 0.8116], [-7.7048, 1.0032], [-7.6916, 1.0988], [

问题 In OpenCV for Android, the function org.opencv.Calib3d.findHomography(..) returns the homogeneous transformation matrix. For example, this only returns the homography: Mat homography = Calib3d.findHomography(points1, points2, Calib3d.RANSAC, 0.5); Is there a way to return the points that RANSAC actually uses from the Android OpenCV API? 回答1: Update I am not sure whether it's a new addition to OpenCV or I've just missed it, but the findHomography() function actually can give you the inliers

问题 I am using to compile and run code from Features2D + Homography to find a known object tutorial, and I am getting this OpenCV Error: Assertion failed (npoints >= 0 && points2.checkVector(2) == npoint s && points1.type() == points2.type()) in unknown function, file c:\Users\vp\wor k\ocv\opencv\modules\calib3d\src\fundam.cpp, line 1062 run-time error. after debugging I find that the program is crashing at findHomography function. Unhandled exception at 0x760ab727 in OpenCVTemplateMatch.exe:

问题 I've got an algorithm that calculates the homography of a number of markers in a single image, using OpenCV's findHomography . This works fine, but due to the size of the markers/resolution of the images, the rotation calculated is often quite inaccurate (mainly around the x and z axes of the marker, assuming y is up). I'd love to find a way to improve this. I have a hypothesis that the fact that I know all the markers are on the same plane (they're on a table) should help improve the

问题 I've got an algorithm that calculates the homography of a number of markers in a single image, using OpenCV's findHomography . This works fine, but due to the size of the markers/resolution of the images, the rotation calculated is often quite inaccurate (mainly around the x and z axes of the marker, assuming y is up). I'd love to find a way to improve this. I have a hypothesis that the fact that I know all the markers are on the same plane (they're on a table) should help improve the

问题 I'd like to get homography matrix to Bird's eye view and I know the projection Matrix of the camera. Is there any relation between them? Thanks. 回答1: A projection matrix is defined as a product of camera's intrinsic (e.g. focal length, principal points, etc.) and extrinsic (rotation and translation) matrices. The question is w.r.t what your rotation and translation are? For example, I can imagine another camera or an object in 3D with respect to which you have these rotations and translations

问题 I'd like to get homography matrix to Bird's eye view and I know the projection Matrix of the camera. Is there any relation between them? Thanks. 回答1: A projection matrix is defined as a product of camera's intrinsic (e.g. focal length, principal points, etc.) and extrinsic (rotation and translation) matrices. The question is w.r.t what your rotation and translation are? For example, I can imagine another camera or an object in 3D with respect to which you have these rotations and translations