I want to compare the two images below, but none of the codes I have tried produce any meaningful output. Here are the pictures :
Orginal
Changed

Desired Result

First, the sizes of the pictures are different and there is also color difference. That’s why no method I tried could give me the results I wanted. Here are the methods I tried and their results :

The Code :

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

int main(int argc, char** argv)
{
    if (argc != 3)
    {
        cout << "Usage: <Program Name> <Image1> <Image2>" << endl;
        return -1;
    }

    Mat img1 = imread(argv[1], IMREAD_COLOR);
    Mat img2 = imread(argv[2], IMREAD_COLOR);

    if (img1.empty() || img2.empty())
    {
        cout << "Could not open or find the image" << endl;
        return -1;
    }

    // Resize img2 to match the size of img1
    resize(img2, img2, img1.size());

    Mat diff, diffGray, thresh;
    absdiff(img1, img2, diff);
    cvtColor(diff, diffGray, COLOR_BGR2GRAY);
    threshold(diffGray, thresh, 30, 255, THRESH_BINARY);

    // Create a mask with red color where differences are found
    Mat redMask = Mat::zeros(img1.size(), img1.type());
    redMask.setTo(Scalar(0, 0, 255), thresh);

    // Apply the red mask to the original image
    img1.setTo(Scalar(0, 0, 255), thresh);

    // Save the result
    imwrite("differences.png", img1);

    namedWindow("Differences", WINDOW_NORMAL);
    imshow("Differences", img1);
    waitKey(0);

    return 0;
}

The Result

I also tried the methods below, but the result was still the same :

Detect and visualize differences between two images with OpenCV Python

Checking images for similarity with OpenCV

Comparing two images/pictures, and mark the difference