How to aplly a kernel to an ofImage?

PowerRanger · May 16, 2015, 3:09pm

Hi all.

How can i apply a kernel like this:

float kernel[3][3] = {{ -1, -1, -1},
{ -1, 9, -1},
{ -1, -1, -1}};

to an ofImage.

my Regards.

hubris · May 16, 2015, 10:29pm

Hi there!

Do you want to do it on the CPU or GPU?

micuat · May 18, 2015, 9:08pm

You should check ofxCv for ofImage to cv::Mat conversion: https://github.com/kylemcdonald/ofxCv

Using OpenCV, you can do something like

	ofFloatImage img;
	img.loadImage(ofToDataPath("image.jpg"));
	cv::Mat src = ofxCv::toCv(img);
	cv::Mat kernel = (cv::Mat1f(3,3)<<-1,-1,-1,-1,9,-1,-1,-1,-1);
	cv::Mat dst;
	cv::filter2D(src, dst, CV_32F, kernel);
	ofxCv::toOf(dst, img);
	img.update();