Crop image to smallest size by removing transparent pixels in java

Question

I have a sprite sheet which has each image centered in a 32x32 cell. The actual images are not 32x32, but slightly smaller. What I\'d like to do is take a cell and crop the tr

Answer 1

A simple fix for code above. I used the median for RGB and fixed the min() function of x and y:

private static BufferedImage trim(BufferedImage img) {
    int width = img.getWidth();
    int height = img.getHeight();

    int top = height / 2;
    int bottom = top;

    int left = width / 2 ;
    int right = left;

    for (int x = 0; x < width; x++) {
        for (int y = 0; y < height; y++) {
            if (isFg(img.getRGB(x, y))){

                top    = Math.min(top, y);
                bottom = Math.max(bottom, y);

                left   = Math.min(left, x);
                right  = Math.max(right, x);

            }
        }
    }

    return img.getSubimage(left, top, right - left, bottom - top);
}

private static boolean isFg(int v) {
    Color c = new Color(v);
    return(isColor((c.getRed() + c.getGreen() + c.getBlue())/2));
}

private static boolean isColor(int c) {
    return c > 0 && c < 255;
}