Template matching with matchTemplate is not good when your object is rotated or scaled in scene. You should try openCV function from Features2D Framework. For example SIFT or SURF descriptors, and FLANN matcher. Also, you will need findHomography method. Here is a good example of finding rotated object in scene. Update: In short, algorithm is … Read more
What you’re doing in your code is actually not correlation at all. You are using the template and performing convolution with the input image. If you recall from the Fourier Transform, the multiplication of the spectra of two signals is equivalent to the convolution of the two signals in time/spatial domain. Basically, what you are … Read more
It doesn’t seem like OpenCV handles alpha the way you want it to. You have two options: Write your own cross-correlation method that will use the alpha channel Transform your images so your alpha channel becomes irrelevant Since the first option is straightforward, I will explore the second option here. I’m going to re-use the … Read more
I was facing the same problem you did. No source in Java available. Some search in the JavaDoc and some hints for const values later, I wrote this, which is almost the sample code above written in Java: package opencv; import org.opencv.core.Core; import org.opencv.core.Core.MinMaxLocResult; import org.opencv.core.CvType; import org.opencv.core.Mat; import org.opencv.core.Point; import org.opencv.core.Scalar; import org.opencv.highgui.Highgui; import … Read more