homography

Homographic image transformation issue for sattelite images

由 半世苍凉 提交于 2019-12-11 01:33:21
问题 I want to apply homography to the satellite images. I found this post quite helpful. So I decided to use the same Matlab code. im = imread('cameraman.tif'); n = [0;0;-1]; d = Inf theta = 60*pi/180; R = [ 1 0 0 ; 0 cos(theta) -sin(theta); 0 sin(theta) cos(theta)]; t = [0;0;0]; K=[300 0 0; 0 300 0; 0 0 1]; H=K*R/K-1/d*K*t*n'*K; img=imagehomog(im,H','c'); figure;imshow(img) but the output is just the small box. I am using MATLAB 2015b EDIT Homography using imtransform and maketform n = [0;0;-1];

How to detect a quadrilateral shape in an image in Java?

由 核能气质少年 提交于 2019-12-10 17:27:56
问题 I want to detect a quadrilateral shape in an image in Java. I can use the HoughLinesP method in OpenCV (using javaCV for opencv java binding) to detect line segments. But I can't figure out how to detect a quadrilateral shape - is there another method for that or some way to use the hough lines? Also once the corners of the quadrilateral are detected, I want it to return a rectangle just like this class does - http://www.aforgenet.com/framework/docs/html/7039a71d-a87d-47ef-7907-ad873118e374

Laser Projector Calibration in 3D Space

由 混江龙づ霸主 提交于 2019-12-10 11:34:20
问题 I am working on a solution for calibrating a laser projector in the real world. There are a few goals for this project. 1. Take in a minimum of four points measured in the real world in 3d space that represent the projection surface. 2. Take in coordinates from the laser that are equivalent to the points received in part 1 3. Determine if the calibration file matches the real world captured points and show a deviation between the coordinate spaces 4. Using the data from the previous steps,

Transforming 2D image coordinates to 3D world coordinates with z = 0

由 北慕城南 提交于 2019-12-09 18:47:52
问题 OpenCV => 3.2 Operating System / Platform => Windows 64 Bit Compiler => Visual Studio 2015 I am currently working on my project which involves vehicle detection and tracking and estimating and optimizing a cuboid around the vehicle. For that I have accomplished detection and tracking of vehicles and I need to find the 3-D world coordinates of the image points of the edges of the bounding boxes of the vehicles and then estimate the world coordinates of the edges of the cuboid and the project

Python Rotate image about camera axis

由 て烟熏妆下的殇ゞ 提交于 2019-12-09 09:46:08
问题 Say I have an image which I have obtained after applying a homography transformation H to some original image. The original image is not shown. The result of the homography H applied to the original image is this image: I want to rotate this image by 30 degrees about a suitable axis (possibly where a camera would be located, if there was one) to get this image: How can I apply this rotation transformation using python if I don't know the camera parameters? I can only specify the degrees by

rotation and translation matrix from homography opencv

由 北城以北 提交于 2019-12-08 07:04:33
问题 I'm working on an android application in java,I calculated homography with opencv using findHomography(), how I can find the matrix of the camera pose containing the rotation and translation through homography Mat homography = Calib3d.findHomography(ReferencePoints2, ReferencePoints1,0,Calib3d.RANSAC); 回答1: You need to know the intrinsic parameters of the camera to do that. Considers the z=0 plane. The point X=(x,y,0,1)' is projected to the image as p=P*X. Now use the decomposition P=K[R t],

Laser Projector Calibration in 3D Space

由 亡梦爱人 提交于 2019-12-06 15:54:46
I am working on a solution for calibrating a laser projector in the real world. There are a few goals for this project. 1. Take in a minimum of four points measured in the real world in 3d space that represent the projection surface. 2. Take in coordinates from the laser that are equivalent to the points received in part 1 3. Determine if the calibration file matches the real world captured points and show a deviation between the coordinate spaces 4. Using the data from the previous steps, take coordinates in 3d real world space and translate them to laser coordinates. Example: A rectangular

How to use OpenGL to emulate OpenCV's warpPerspective functionality (perspective transform)

由 社会主义新天地 提交于 2019-12-06 04:22:41
问题 I've done image warping using OpenCV in Python and C++, see the Coca Cola logo warped in place in the corners I had selected: Using the following images: and this: Full album with transition pics and description here I need to do exactly this, but in OpenGL. I'll have: Corners inside which I've to map the warped image A homography matrix that maps the transformation of the logo image into the logo image you see inside the final image (using OpenCV's warpPerspective), something like this: [[ 2

Getting the 5 points used by RANSAC in findHomography (OpenCV for Android)

由 别说谁变了你拦得住时间么 提交于 2019-12-06 02:23:17
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? Sam 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 (OpenCV 2.4.2). The last parameter, mask , which is empty by default, will be filled with ones (or 255) at

2D-3D homography matrix estimation

由 ≡放荡痞女 提交于 2019-12-06 00:52:42
问题 I am working with my Kinect on some 2D 3D image processing. Here is my problem: I have points in 3D (x,y,z) which lie on a plane. I also know the coordinates of the points on the RGB image (x,y). Now I want to estimate a 2D-3D homography matrix to estimate the (x1,y1,z1) coordinates to a random (x1,y1) point. I think that is possible, but I don't know where to start. Thanks! 回答1: What you're looking for is a camera projection matrix, not a homography. A homography maps a plane seen from a
订阅 homography