perspectivecamera

问题 I have four corners extracted from a sourceImage : src_vertices[0] = corners[upperLeft]; src_vertices[1] = corners[upperRight]; src_vertices[2] = corners[downLeft]; src_vertices[3] = corners[downRight]; These four corners are warped to destinationImage like that: dst_vertices[0] = Point(0,0); dst_vertices[1] = Point(width, 0); dst_vertices[2] = Point(0, height); dst_vertices[3] = Point(width, height); Mat warpPerspectiveMatrix = getPerspectiveTransform(src_vertices, dst_vertices); cv::Size

问题 I have two cameras in one scene and one viewport and one renderer. I toggle (using html buttons) between cameras. THE PROBLEMS Problem 1 For camera1 there is no response from moving the mouse. When I toggle to camera2 the orbit control works fine. Toggling back to camera1 there is still no response from moving the mouse. jsfiddle v1 Original (no response from camera1) jsfiddle.net/steveow/xu0k1z75/ UPDATE: Problem 1, Fixed by Stallion - avoid setting camera position to (0,0,0). Problem 2 For

问题 I have an object moving about in a flat 2D coordinate system (0-1000,0-1000). In a 3D space coordinate system, I have a sphere and a camera looking at the sphere. I then want to convert these 2D coordinates to the 3D world/space coordinates and then move this object around the surface of the sphere. So, it's basically like converting Lat/Long into a 3D spacial coordinate. Currently I'm using setFromSpherical() but maybe I'm using it the wrong way. Vector3 my3DVector = new Vector3(0,0,0);

问题 I am trying to determine camera position in world coordinates, relative to a fiducial position based on fiducial marker found in a scene. My methodology for determining the viewMatrix is described here: Determine camera pose? I have the rotation and translation, [R|t], from the trained marker to the scene image. Given camera calibration training, and thus the camera intrinsic results, I should be able to discern the cameras position in world coordinates based on the perspective & orientation

问题 I need to sync trackball controls and camera with the directional light. My case scenario: Init an empty scene with camera, lights and controls. Load a bufferGeometry obj, get its centroid and set camera and controls position and target relative to the obj centroid. Basically I simply set camera position and controls.target with: camera.lookAt( position ); camera.position = position; controls.target.copy( position ); where position is a Three.Vector3 obj. Directional light has to sync

问题 I'm having some strange behaviour inside a WPF app I'm writing. When I run an animation on the camera position (a Point3DAnimation on PerspectiveCamera.PositionProperty), I get really bad flickering artifacts inside the application. The 3D-rendered object seems to disappear for certain frames and allows the background of the window to show through. I've written a very simple sample application below to demonstrate the problem on my machine. To use it, just compile it and use the arrow up and

问题 I use two projection matrices P1 and P2 (for example I'm using dinosaur dataset) and I need to compute the fundamental matrix F. So I use two Matlab functions: Peter Kovesi's function: www.csse.uwa.edu.au/~pk/Research/MatlabFns/Projective/fundfromcameras.m Zisserman: www.robots.ox.ac.uk/~vgg/hzbook/code/vgg_multiview/vgg_F_from_P.m These functions should do the same thing, but I have a different F value ! How it's possible? Which is the right functions? If two points X1 and X2 are "the same"

问题 I am trying to determine camera pose based on fiducial marker found in a scene. Fiducial: http://tinypic.com/view.php?pic=4r6k3q&s=8#.VNLnWTVVK1E Current process: Use SIFT for feature detection Use SIFT for descriptor extraction Use FLANN for matching Find the homography using CV_RANSAC Identify the corners of the fiducial Identify corners of the fiducial in the scene using perspectiveTransform() Draw lines around corners (i.e. prove that it found the fiducial in the scene Run camera

问题 How can I make camera rotate in circle around a 3d object in javaFX? I know i can rotate it around itself using camera.setRotate(angle); but i want an object to be still and the camera to rotate and point to the same spot like the rotation axis is that object. 回答1: The general technique is defined the answers to: RotateTransition around a pivot? You define a rotate transform and then use a timeline (or animation timer) to animate the angle of the rotate transform as appropriate. If you want

问题 Input: 53490 3D points and for each point (xyz) and color (rgb) of a head Output: 2D face image as viewed from a particular position / direction Platform: Matlab C/C++ After study, I found the steps to be implemented Perspective Projection http://en.wikipedia.org/wiki/3D_projection Z-buffering http://en.wikipedia.org/wiki/Z-buffering Phong reflection model http://en.wikipedia.org/wiki/Phong_reflection_model I implemented the above 3 steps in Matlab. But it takes 8 min for the execution. The