How to resize an image in Java with OpenCV?
I think, you want this.
e.g.
Mat croppedimage = cropImage(image,rect);
Mat resizeimage = new Mat();
Size sz = new Size(100,100);
Imgproc.resize( croppedimage, resizeimage, sz );
If you want to scale an image using OpenCV java then do the following:
import static org.opencv.imgproc.Imgproc.*;
import static org.opencv.imgcodecs.Imgcodecs.imread;
Main code:
Mat src = imread("imageName.jpg");
Mat resizeimage = new Mat();
Size scaleSize = new Size(300,200);
resize(src, resizeimage, scaleSize , 0, 0, INTER_AREA);
For downscaling it is recommended to use: INTER_AREA and for upscaling use INTER_CUBIC
For more details: OpenCV Ref for Resize
Please read manual for c++ method Resize it's the same to java.
You can choose a type of interpolation. In some cases it's important for a best result.
Mat croppedImage = cropImage(image,rect); Mat resizeImage = new Mat(anyHeight, anyWidth, croppedImage.type()); int interpolation = Imgproc.INTER_CUBIC; Imgproc.resize(croppedImage, resizeImage, resizeImage.size(), 0, 0, interpolation );