Opencv：将使用视频的代码更改为使用轨迹栏进行颜色检测的图像

Question

我有一个项目，我需要从树叶图像中检测特定颜色，例如绿色、棕色和黄色。我发现这个教程 (http://opencv-srf.blogspot.com.br/2010/09/object-detection-using-color-seperation.html) 解释了如何创建实时轨迹栏以找到最佳值，但它使用来自网络摄像头的图像，我想将它与图片一起使用。你们能帮我做一下吗？

谢谢。

Answer 1

这是对 HSV 图像进行阈值处理的代码，使用轨迹栏选择范围。

请注意，与视频不同（如here所述），我使用morphologyEx进行形态学操作，并用C++函数[=13]替换了C风格cvCreateTrackbar =].

代码中的注释要清楚。如果有什么不清楚的地方请联系我：

#include <opencv2/opencv.hpp>
#include <iostream>
using namespace cv;
using namespace std;

int main(int argc, char** argv)
{
    // Load BGR image
    Mat3b bgr = imread("path_to_image");
    if (bgr.empty()) 
    {
        cout << "Cannot open the image" << endl;
        return -1;
    }

    // Transform to HSV
    Mat3b hsv;
    cvtColor(bgr, hsv, COLOR_BGR2HSV); 

    // Create a window called "Control"
    namedWindow("Control", CV_WINDOW_AUTOSIZE); 

    // Set starting values for ranges
    int iLowH = 0;
    int iHighH = 179;

    int iLowS = 0;
    int iHighS = 255;

    int iLowV = 0;
    int iHighV = 255;

    //Create trackbars in "Control" window
    createTrackbar("LowH", "Control", &iLowH, 179); //Hue (0 - 179)
    createTrackbar("HighH", "Control", &iHighH, 179);

    createTrackbar("LowS", "Control", &iLowS, 255); //Saturation (0 - 255)
    createTrackbar("HighS", "Control", &iHighS, 255);

    createTrackbar("LowV", "Control", &iLowV, 255); //Value (0 - 255)
    createTrackbar("HighV", "Control", &iHighV, 255);

    //Show the original image
    imshow("Original", bgr); 

    // Create kernel for morphological operation
    Mat kernel = getStructuringElement(MORPH_ELLIPSE, Size(5, 5));

    // Infinte loop, until user press "esc"
    while (true)
    {
        Mat mask;
        inRange(hsv, Scalar(iLowH, iLowS, iLowV), Scalar(iHighH, iHighS, iHighV), mask); //Threshold the image

        //morphological opening (remove small objects from the foreground)
        morphologyEx(mask, mask, MORPH_OPEN, kernel);

        //morphological closing (fill small holes in the foreground)
        morphologyEx(mask, mask, MORPH_CLOSE, kernel);

        //Show the thresholded image
        imshow("Thresholded Image", mask); 

        if (waitKey(30) == 27) //wait for 'esc' key press for 30ms. If 'esc' key is pressed, break loop
        {
            cout << "esc key is pressed by user" << endl;
            break;
        }
    }
    return 0;
}

Opencv：将使用视频的代码更改为使用轨迹栏进行颜色检测的图像

Opencv: Changing a code that uses video to an image for color detection using trackbars

c++

opencv

image

image-processing

computer-vision