c++ - 将图像缓冲区的指针传递给 OpenCV 并更改饱和度？

Question

我想传递我的图像缓冲区的指针，更改饱和度并立即查看结果。但是更改没有应用到我的缓冲区中，也没有更改。

void changeSaturation(void* buffer,int width, int height)
{
  Mat matObject(width, height, CV_8UC4, buffer);
  m_matSource = matObject;
  Mat newMat = m_matSource.clone();

  // BGR to HSV
  cvtColor(matSource, matSource, CV_BGR2HSV);
  for(int i = 0; i < newMat.rows; ++i)
   {
     for(int j = 0; j < newMat.cols; ++j)
     {
        newMat.at<cv::Vec3b>(i, j)[1] = 255; //saturationValue;
     }
   }

// HSV back to BGR
 cvtColor(newMat, m_matSource, CV_HSV2BGR); // here m_matSource->data change

如何将更改应用到我的缓冲区？

Answer 1

我在尝试重现您的问题时重构了您的代码，并在此过程中修复了它。您将源代码克隆到 newMat 中，然后更改了原始图像的色彩空间，然后继续完全忽略新修改的图像。试试这个:

void changeSaturation(Mat& image)
{
    Mat result(image.rows, image.cols, image.type());

    // BGR to HSV
    cvtColor(image, result, CV_BGR2HSV);
    for(int i = 0; i < result.rows; ++i)
    {
        for(int j = 0; j < result.cols; ++j)
            result.at<cv::Vec3b>(i, j)[1] = 255; //saturationValue;
    }

// HSV back to BGR
    cvtColor(result, result, CV_HSV2BGR); // here m_matSource->data change

    namedWindow("Original");
    imshow("Original",image);

    namedWindow("Duplicate");
    imshow("Duplicate",result);
}


int main()
{
    Mat image;

    image = imread("C:/Users/Public/Pictures/Sample Pictures/Desert.jpg");

    changeSaturation(image);
    waitKey(0);
}

编辑

修改输入图像:

void changeSaturation(Mat& image)
{
    // BGR to HSV
    cvtColor(image, image, CV_BGR2HSV);
    for(int i = 0; i < image.rows; ++i)
    {
        for(int j = 0; j < image.cols; ++j)
            image.at<cv::Vec3b>(i, j)[1] = 255; //saturationValue;
    }

    // HSV back to BGR
    cvtColor(image, image, CV_HSV2BGR); // here m_matSource->data change
}

下一个编辑

这现在具有(几乎)原始函数签名:

void changeSaturation(uchar* buffer, int rows, int cols, int type)
{
    Mat image(rows, cols, type, buffer);
    Mat result;
    // BGR to HSV
    cvtColor(image, result, CV_BGR2HSV);
    for(int i = 0; i < result.rows; ++i)
    {
        for(int j = 0; j < result.cols; ++j)
            result.at<cv::Vec3b>(i, j)[1] = 255;
    }

    // HSV back to BGR
    cvtColor(result, image, CV_HSV2BGR);
}

int main()
{
    Mat image;

    image = imread("C:/Users/Public/Pictures/Sample Pictures/Desert.jpg");

    changeSaturation(image.data, image.rows, image.cols, image.type());

    imshow("Original",image);
    waitKey(0);
}