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
Python: Reads image blob.jpg and performs blob detection with different parameters. #!/usr/bin/python # Standard imports import cv2 import numpy as np; # Read image im = cv2.imread(“blob.jpg”) # Setup SimpleBlobDetector parameters. params = cv2.SimpleBlobDetector_Params() # Change thresholds params.minThreshold = 10 params.maxThreshold = 200 # Filter by Area. params.filterByArea = True params.minArea = 1500 # Filter … 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
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
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
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
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
If you have only these regular shapes, there is a simple procedure as follows : Find Contours in the image ( image should be binary as given in your question) Approximate each contour using approxPolyDP function. First, check number of elements in the approximated contours of all the shapes. It is to recognize the shape. … Read more