OpenCV

问题 I'm doing a very simple program on EMGU CV, so I need to take a screenshot of what my camera is recording and save it in a specific folder, here follows my code of camera capture: ImageViewer viewer = new ImageViewer(); VideoCapture capture = new VideoCapture(); Application.Idle += new EventHandler(delegate (object sender, EventArgs e) { viewer.Image = capture.QueryFrame(); }); viewer.ShowDialog(); I apologize for the simple terms, I still really noob in programming. 回答1: It seems like you

问题 Using Opencv.js I have acquired the contours in an image. using some selection function I have collected a subset of these contours. Say they are in the list of contours: var suitableContours = []; I need to know draw these contours using opencv. If this were python I could do cv.drawContours(img, [suitableContours[cnt]], 0, [255, 0, 0, 255], 2); Assume by the point I want to draw the contours I don't have access to the original image nor the mask nor the original contour list, only the

问题 Using Opencv.js I have acquired the contours in an image. using some selection function I have collected a subset of these contours. Say they are in the list of contours: var suitableContours = []; I need to know draw these contours using opencv. If this were python I could do cv.drawContours(img, [suitableContours[cnt]], 0, [255, 0, 0, 255], 2); Assume by the point I want to draw the contours I don't have access to the original image nor the mask nor the original contour list, only the

问题 I have installed opencv, qt, qt creator, cmake on ubuntu 15.10 through VMware on windows. The opencv is installed in this directory: /home/majidalaeinia/opencv/ The project repository is cloned in this directory: /home/majidalaeinia/Desktop/imgwarp-opencv/ I want to run the project through its CMakeLists.txt in qt creator and when I press Build now on qt creator, I get the following errors: error: cannot find -lopencv_imgcodecs error: collect2: error: ld returned 1 exit status Where is the

问题 I have successfully built opencv with WITH_CUDA=on . but I'm still facing this error error: namespace "cv::cuda" has no member "resize" . it is weird that the IDE suggests me that there is a resize function in that namespace but it fails on compile. Does anyone know how to tackle this matter? #include "opencv2/highgui.hpp" #include "opencv2/imgproc.hpp" #include "opencv2/video/background_segm.hpp" #include "opencv2/video/tracking.hpp" #include "opencv2/cudev/ptr2d/gpumat.hpp" #include

问题 I have a very basic program to test that OpenCV works. #include <opencv2/opencv.hpp> int main() { cv::namedWindow("Window", CV_WINDOW_AUTOSIZE); cv::VideoCapture video_capture; video_capture.open(0); while (true) { cv::Mat image; video_capture.read(image); cv::imshow("Window", image); if (cv::waitKey(1) == 27) { break; } } return 0; } And a CMakeLists.txt file that finds OpenCV like so: find_package(OpenCV REQUIRED) ... target_link_libraries(Project ${OpenCV_LIBS}) This works on Mac OSX 10.10

问题 How to apply cv2.boundingRect to a np.array of points ? The following code produces an error. points = np.array([[1, 2], [3, 4]], dtype=np.float32) import cv2 cv2.boundingRect(points) Error: OpenCV Error: Unsupported format or combination of formats (The image/matrix format is not supported by the function) in cvBoundingRect, file /build/buildd/opencv-2.4.8+dfsg1/modules/imgproc/src/shapedescr.cpp, line 97 File "<ipython-input-23-42e84e11f1a7>", line 1, in <module> cv2.boundingRect(points)

问题 I want to display a FHD live-stream (25 fps) and overlay some (changing) text. For this I essentially use the code below. Basically it is Load frame ( cv::putText skipped here) Display frame if it's a multiple of delay but the code is super super slow compared to e.g. mpv and consumes way to much cpu-time ( cv::useOptimized() == true ). So far delay is my inconvenient fiddle-parameter to somehow make it feasible. delay == 1 results in 180 % CPU usage (full frame-rate) delay == 5 results in 80

问题 I have a very basic program to test that OpenCV works. #include <opencv2/opencv.hpp> int main() { cv::namedWindow("Window", CV_WINDOW_AUTOSIZE); cv::VideoCapture video_capture; video_capture.open(0); while (true) { cv::Mat image; video_capture.read(image); cv::imshow("Window", image); if (cv::waitKey(1) == 27) { break; } } return 0; } And a CMakeLists.txt file that finds OpenCV like so: find_package(OpenCV REQUIRED) ... target_link_libraries(Project ${OpenCV_LIBS}) This works on Mac OSX 10.10

问题 My overall goal is to crop several regions from an input mirax (.mrxs) slide image to JPEG output files. Here is what one of these images looks like: Note that the darker grey area is part of the image, and the regions I ultimately wish to extract in JPEG format are the 3 black square regions. Now, for the specifics: I'm able to extract the color channels from the mirax image into 3 separate TIFF files using vips on the command line: vips extract_band INPUT.mrxs OUTPUT.tiff[tile,compression