opencv3.0

问题 I want to distort and rectified my stereo images. For which I used Opencv 3.3 in Python 2.7. Code I used is : import cv2 import numpy as np cameraMatrixL = np.load('mtx_left.npy') distCoeffsL = np.load('dist_left.npy') cameraMatrixR = np.load('mtx_right.npy') distCoeffsR = np.load('dist_right.npy') R = np.load('R.npy') T = np.load('T.npy') imgleft = cv2.imread('D:\python\camera calibration and 3d const\left\left60.png',0) imgright = cv2.imread('D:\python\camera calibration and 3d const\Right

问题 I am using OpenCV 3.0 beta. I tried to create a face recogniser using createLBPHFaceRecognizer(); class as, **Ptr <FaceRecognizer> model = createLBPHFaceRecognizer();** the error I have is **error: 'createLBPHFaceRecognizer' was not declared in this scope** I have researched and found that the class exists in contrib module of opencv2 (opencv2/contrib/contrib.hpp) in previous versions of OpenCV But this module is not available in opencv 3.0 beta. So where are the recogniser classes defined in

问题 I tried to build OpenCV 3.1.0 on my Raspberry Pi 2B. Unfortunetly, when I trying: cmake -D CMAKE_BUILD_TYPE=RELEASE \ -D CMAKE_INSTALL_PREFIX=/usr/local \ -D INSTALL_C_EXAMPLES=OFF \ -D INSTALL_PYTHON_EXAMPLES=OFF /home/pi/Downloads/opencv-3.1.0 It gave me a error :( : CMake Error: The source "/home/pi/Downloads/opencv-3.1.0/CMakeLists.txt" does not match the source "/home/pi/Downloads/opencv-3.1.0/modules/CMakeLists.txt" used to generate cache. Re-run cmake with a different source directory.

问题 Having just upgraded from opencv-2.4.11, KNearest seems to be missing In [27]: import cv2 In [28]: print(cv2.__version__) 3.0.0-beta In [29]: cv2.KNearest() --------------------------------------------------------------------------- AttributeError Traceback (most recent call last) <ipython-input-29-d2ea29abad59> in <module>() ----> 1 cv2.KNearest() AttributeError: 'module' object has no attribute 'KNearest' In [30]: cv2.K cv2.KAZE_DIFF_CHARBONNIER cv2.KAZE_DIFF_WEICKERT cv2.KMEANS_RANDOM

问题 On the website colorizer.org, they have an HSV range of H=0-360, S=0-100, V=0-100. We are also aware that the HSV range in OpenCV is H=0-180, S=0-255, V=0-255. I wanted to select a range for any shade of (what we perceive as) blue color, so I looked at colorizer.org, and saw that blue Hue ranges roughly from 170 to 270. So I scaled this Hue range to OpenCV by dividing by 2, which gives 85-135. Now, I took the following screenshot of color [H=216, S=96, V=67] from the preview at the website

问题 I'm trying to use the STAR detector in openCV 3, and it's throwing an error: import cv2 image = cv2.imread('grand_central_terminal.png') gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY) star = cv2.xfeatures2d.StarDetector_create() (kps, descs) = star.detectAndCompute(gray, None) print("# of keypoints: {}".format(len(kps))) # should be 459 The error it gives is: Traceback (most recent call last): File "quiz.py", line 8, in <module> (kps, descs) = star.detectAndCompute(gray, None) cv2.error:

问题 I'm trying to use the STAR detector in openCV 3, and it's throwing an error: import cv2 image = cv2.imread('grand_central_terminal.png') gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY) star = cv2.xfeatures2d.StarDetector_create() (kps, descs) = star.detectAndCompute(gray, None) print("# of keypoints: {}".format(len(kps))) # should be 459 The error it gives is: Traceback (most recent call last): File "quiz.py", line 8, in <module> (kps, descs) = star.detectAndCompute(gray, None) cv2.error:

问题 I am trying to use OpenCV3 for video file reading. string packageRootPath = ros::package::getPath("visensor_dgem"); string videoFullPath = packageRootPath + "/dump/Video.avi"; cout << videoFullPath << endl; cv::VideoCapture cap; bool flag = cap.open( videoFullPath ); if( flag ) cout << "flag true\n"; else cout << "flag false\n"; The path to the video file is correct. I am guessing my issue has to do with the video codecs. The program compiles file, however when I run the code I get flag false

问题 I am migrating my OpenCV 2.4.2 to OpenCV 3.0 for using OpenCL performance throught the Transparent-API. But, I note that some algorithms take the same time in CPU or GPU implementation. I searched in the official documentation, but I didn't find the answer. How to know if an algorithm has an automatic OpenCL translation in the Transparent API or not ? 回答1: If you have amd gpu, use codexl and create a new codexl project, attach your project and start session from codexl, or, start your project

问题 Well, OpenCv comes with its function findCheckerboardCorners() in C++ which goes like bool findChessboardCorners(InputArray image, Size patternSize, OutputArray corners, int flags=CALIB_CB_ADAPTIVE_THRESH+CALIB_CB_NORMALIZE_IMAGE ) After using this function for a while, one thing that i understood was that the pattern size must comply with the image to a very good extent, else the algorithm refuses to detect any Chessboard altogether. I was wondering if there were any random image of a