The error you’re seeing is that CMake cannot find a FindOpenCV.cmake file, because cmake doesn’t include one out of the box. Therefore you need to find one and put it where cmake can find it: You can find a good start here. If you’re feeling adventurous you can also write your own. Then add it … Read more
First: create a folder Project containing two subfolders src and include, and a file called CMakeLists.txt. Second: Put your cpp inside the src folder and your headers in the include folders. Third: Your CMakeLists.txt should look like this: cmake_minimum_required(VERSION 2.8) PROJECT (name) find_package(OpenCV REQUIRED ) set( NAME_SRC src/main.cpp ) set( NAME_HEADERS include/header.h ) INCLUDE_DIRECTORIES( ${CMAKE_CURRENT_SOURCE_DIR}/include … Read more
I created this app using opencv. Is this the effect you are referring to? I basically coded the formula shown on wikipedia’s “Distortion(optics)” I can show the code if needed Update: OK, so below is the actual code written in c++ using opencv (not documented so feel free to ask for explanations): The program recieves … Read more
July 12 Edit: This post inspired GitHub repos providing functions to accomplish this task; one for a padded warpAffine() and another for a padded warpPerspective(). Check out the Python version or the C++ version. Transformations shift the location of pixels What any transformation does is takes your point coordinates (x, y) and maps them to … Read more
Given your configuration, errors of 20-40mm at the edges are average. It looks like you’ve done everything well. Without modifying camera/system configuration, doing better will be hard. You can try to redo camera calibration and hope for better results, but this will not improve them alot (and you may eventually get worse results, so don’t … Read more
After MUCH trial and error, I managed to write a function to do it. here it is for anyone else who might want it: #include “stdafx.h” #include “opencv2/core/core.hpp” #include “opencv2/imgproc/imgproc.hpp” #include <opencv2/highgui/highgui.hpp> #include <Windows.h> #include <iostream> #include <string> using namespace std; using namespace cv; Mat hwnd2mat(HWND hwnd){ HDC hwindowDC,hwindowCompatibleDC; int height,width,srcheight,srcwidth; HBITMAP hbwindow; Mat src; … Read more
If you have your Homography, you can calculate the camera pose with something like this: void cameraPoseFromHomography(const Mat& H, Mat& pose) { pose = Mat::eye(3, 4, CV_32FC1); // 3×4 matrix, the camera pose float norm1 = (float)norm(H.col(0)); float norm2 = (float)norm(H.col(1)); float tnorm = (norm1 + norm2) / 2.0f; // Normalization value Mat p1 = … Read more
Here is a handy function you can use to help with identifying your opencv matrices at runtime. I find it useful for debugging, at least. string type2str(int type) { string r; uchar depth = type & CV_MAT_DEPTH_MASK; uchar chans = 1 + (type >> CV_CN_SHIFT); switch ( depth ) { case CV_8U: r = “8U”; … Read more
First of all: the function minMaxLoc finds only the global minimum and global maximum for a given input, so it is mostly useless for determining regional minima and/or regional maxima. But your idea is right, extracting markers based on regional minima/maxima for performing a Watershed Transform based on markers is totally fine. Let me try … Read more
Did you mean something like this? it is HSV histogram showed as 3D graph V is ignored to get to 3D (otherwise it would be 4D graph …) if yes then this is how to do it (I do not use OpenCV so adjust it to your needs): convert source image to HSV compute histogram … Read more