[armeabi-v7a] library errors in Face-detection sample
Hello All, I just started of with the tutorials of OpenCV4Android. Am a novice user and started learning with the sample tutorials. I have done some research work before posting out here but I didn't...
View ArticleLine segment detector crashes when no keylines found?
For a particularly small .png image (i.e 200x200) which does not have any keylines, the algorith used to **detect** them crashes. Both...
View Articlefit images with different resolution
Hello, How can I fit and then overlay 2 images which have different resolution ? This is the main image:  I have this one,...
View ArticleIs there suggestion on extracting white line?
 I have some trouble in it. 1.The diffrence of white line with background is not intense enough. 2.The singular threshold is uneffective because the...
View Articleresize,grayscale and equalized necessary?
http://docs.opencv.org/2.4/modules/contrib/doc/facerec/tutorial/facerec_video_recognition.html This reads frames from webcam and checks against csv database and images stored in a directory. So to...
View Articlecamera calibration
Hello, I am working on camera calibration and i used the camera calibration file from opencv and calibrated using the chess board placing at different locations in my required FOV(3x3m). But as i was...
View ArticleCan I calibrate Pinhole and Omnidirectional Cameras in one Setting to get the...
Hi everyone, I'm working with **cv::multicalib::MultiCameraCalibration**. I'm initializing the Calibration with `multicalib::MultiCameraCalibration multiCalib(cameraType, nCamera, inputFilename,...
View ArticleHow to crop multiple objects from an image by drawing Polygon with mouse...
 want to select the coke cans boundaries using mouse clicks and crop them. So need a solution to draw multiple polygons to select objects: **I am...
View ArticleANN_MLP Access violation Exception
i train ann to detect eye state with out problem but when i want to load pre trained file and predict samples this exception occurred : my training image size is 24*24; Exception thrown at...
View Articlehough circle transform error
Hello guys , I am trying to do hough circle transform in order to find pupil in eyeROI.But It doesnt work ..Do you have any idea about how to fix this problem ? Here is the code : #include...
View ArticleDo I need a Cygwin to run OpenCV4Android
It might be a silly question to you all but for a novice user like me it wasn't as you pretend. Am in a Dilemma whether I need to use OpenCV4Android on my Windows 7 Notebook. When am running the...
View ArticleWhy cuda::ORB detectAndCompute's useProvidedKeypoints parameter is forced to...
Hi Everyone, I would like to use cuda::orb compute or detectAndCompute method to describe keypoints that I detect earlier. But when I try to use these methods I got "Assertion failed...
View ArticleUnderstanding the camera matrix
Hello all, I used a chessboard calibration procedure to obtain a camera matrix using OpenCV and python based on this tutorial:...
View ArticlecalcHist() with CV_32F
Hello, To compute a histogram of a CV_8U image (values between 0 and 255) knowing that the upper boundary in `histRange` is exclusive, we have int histSize = 256; float range[] = { 0, 256 } ; const...
View Articleactive appearance model
I have been using the dlib library to detect faces and its working really well. I delved a bit deeper into it and found its based on the concept of active appearance model(AAM) and active shape...
View ArticleCamera Matrix with Extra Optical Elements
Hello, I am using a camera sensor with a fixed focal length lens that has a distortion on it. Normally I would use the OpenCV chessboard routine as is to correct for it, but in this case I have extra...
View ArticleImage averaging for impulse noise
Hello, Why does image averaging ( taking the average of many images ) not work for impulse noise ? I understand the mathematics of why it works for gaussian noise. Since we can treat the noisy image as...
View ArticleCreate a tensor file in C [OpenCV]
Hi, I should create a txt file that represent a tensor in Torch... This is my problem: In a .c file (but I can also use C++ language and I don't know how it is possible...) I have to create a file that...
View Articlewhy Opencv with Qt cmd remains after actual opencv window is closed
i have opencv various versions with Qt 4.x or 5.x build with visual sutdio 2010 when i run my exe, with simple opencv loading an image , waitkey and release , Qt seems to keep open the cmd window if i...
View Articlehow to remove specific rows from a matrix
I want to delete the rows containing all zeros from a matrix... I can do so in MATLAB but how can I do it in OpenCV? I've searched over the internet but could not understand....
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