How to create white border around bitmap?

Question

For example I want a white border of 10pixel around all 4 side of the bitmap. I am not using it for imageview I am currently using this code to crop image. May I know how I could add a white border into it?

public Bitmap scaleCenterCrop(Bitmap source, int newHeight, int newWidth) {
    int sourceWidth = source.getWidth();
    int sourceHeight = source.getHeight();

    // Compute the scaling factors to fit the new height and width, respectively.
    // To cover the final image, the final scaling will be the bigger 
    // of these two.
    float xScale = (float) newWidth / sourceWidth;
    float yScale = (float) newHeight / sourceHeight;
    float scale = Math.max(xScale, yScale);

    // Now get the size of the source bitmap when scaled
    float scaledWidth = scale * sourceWidth;
    float scaledHeight = scale * sourceHeight;

    // Let's find out the upper left coordinates if the scaled bitmap
    // should be centered in the new size give by the parameters
    float left = (newWidth - scaledWidth) / 2;
    float top = (newHeight - scaledHeight) / 2;

    // The target rectangle for the new, scaled version of the source bitmap will now
    // be
    RectF targetRect = new RectF(left, top, left + scaledWidth, top + scaledHeight);

    // Finally, we create a new bitmap of the specified size and draw our new,
    // scaled bitmap onto it.
    Bitmap dest = Bitmap.createBitmap(newWidth, newHeight, source.getConfig());
    Canvas canvas = new Canvas(dest);
    canvas.drawBitmap(source, null, targetRect, null);

    return dest;
}

Answer 1

I wrote a function for this:

private Bitmap addWhiteBorder(Bitmap bmp, int borderSize) {
    Bitmap bmpWithBorder = Bitmap.createBitmap(bmp.getWidth() + borderSize * 2, bmp.getHeight() + borderSize * 2, bmp.getConfig());
    Canvas canvas = new Canvas(bmpWithBorder);
    canvas.drawColor(Color.WHITE);
    canvas.drawBitmap(bmp, borderSize, borderSize, null);
    return bmpWithBorder;
}

Basically it creates a new Bitmap adding 2 * bordersize to each dimension and then paints the original Bitmap over it, offsetting it with bordersize.