OpenCV亮度对比度调节

static void on_track_lightness(int b, void* user_data)
{
  Mat image = *((Mat *)user_data);
  if (image.empty())
    return;
  Mat dst = Mat::zeros(image.size(), image.type());
  Mat m = Mat::zeros(image.size(), image.type());
  addWeighted(image, 1.0, m, 0, b, dst);
  imshow("亮度对比度调节", dst);
}
static void on_track_contrast(int b, void* user_data)
{
  Mat image = *((Mat *)user_data);
  Mat dst = Mat::zeros(image.size(), image.type());
  Mat m = Mat::zeros(image.size(), image.type());
  double contrast = b / 100.0;
  addWeighted(image, contrast, m, 0.0, 0, dst);
  imshow("亮度对比度调节", dst);
}
void on_pushButton_brightness_clicked()
{
  namedWindow("亮度对比度调节", WINDOW_AUTOSIZE);
  
  int lightness = 50;
  int max_value = 100;
  int contrast_value = 100;
  createTrackbar("Value Bar:", "亮度对比度调节", &lightness, max_value, on_track_lightness,(void*)(&img));
  createTrackbar("Constrast Bar:", "亮度对比度调节", &contrast_value, 200, on_track_contrast, (void*)(&img));
  on_track_lightness(50, &img);
}