如何使用Opencv获得两个图像之间的相似和差异

Question

我想比较两个图像并找到相同和不同的图像部分。我厌倦了“cv :: compare和cv :: absdiff”方法，但是对于我的情况哪个方面很有用。两者都显示了不同的结果。那我怎么能完成我想要的任务呢？

Answer 1

以下是如何使用cv::absdiff查找图像相似度的示例：

int main()
{
    cv::Mat input1 = cv::imread("../inputData/Similar1.png");
    cv::Mat input2 = cv::imread("../inputData/Similar2.png");

    cv::Mat diff;
    cv::absdiff(input1, input2, diff);

    cv::Mat diff1Channel;
    // WARNING: this will weight channels differently! - instead you might want some different metric here. e.g. (R+B+G)/3 or MAX(R,G,B)
    cv::cvtColor(diff, diff1Channel, CV_BGR2GRAY);

    float threshold = 30; // pixel may differ only up to "threshold" to count as being "similar"

    cv::Mat mask = diff1Channel < threshold;

    cv::imshow("similar in both images" , mask);

    // use similar regions in new image: Use black as background
    cv::Mat similarRegions(input1.size(), input1.type(), cv::Scalar::all(0));

    // copy masked area
    input1.copyTo(similarRegions, mask);


    cv::imshow("input1", input1);
    cv::imshow("input2", input2);
    cv::imshow("similar regions", similarRegions);
    cv::imwrite("../outputData/Similar_result.png", similarRegions);
    cv::waitKey(0);
    return 0;
}

使用这两个输入：

你会观察到输出（黑色背景）：