when use javavc the memory is always grow up, the version is 4.5.5-1.5.7

    try (PointerScope scope = new PointerScope()) {

        Mat image = Java2DFrameUtils.toMat(bufferedImage);
        Mat grayImage = new Mat(image.rows(), image.cols(), opencv_core.CV_8UC1);
        opencv_imgproc.cvtColor(image, grayImage, opencv_imgproc.COLOR_BGR2GRAY);

        Mat dest = new Mat(image.rows(), image.cols(), opencv_core.CV_8UC1);
        int rows = image.rows();
        int cols = image.cols();
        image.release();

        opencv_core.addWeighted(grayImage, 1.3, dest, -0.5, 0, dest);
        Mat edges = new Mat(rows, cols, opencv_core.CV_8UC1);
        opencv_imgproc.Canny(dest, edges, 50, 150);

        Mat destNoiseFree = new Mat(rows, cols, opencv_core.CV_8UC1);
        opencv_imgproc.medianBlur(dest, destNoiseFree, 5);

        BufferedImage outputImage = Java2DFrameUtils.toBufferedImage(dest);

        grayImage.release();
        edges.release();
        destNoiseFree.release();
        dest.release();
        return outputImage;
    }