Android Bitmap Contour

I'm trying to draw the contour of my drawable, I tried to use Blur, as in this page: How to make glow effect around a bitmap? Its effect is not what I want, I want a 'solid' contou

Solution 1:

There is no outline type filter or mask that I can find, while blur and shadow mask are not very strong. Hence you could create your own effect by using color filter and scale. This example would create a red contour

ColorFilter filter;
filter=new PorterDuffColorFilter(0xFFFF0000, PorterDuff.Mode.SRC_IN);         

paint =new Paint(Paint.ANTI_ALIAS_FLAG);
paint.setColorFilter(filter);

canvas.save();
canvas.scale(1.1f, 1.1f,imageCenterX , imageCenterY);
canvas.drawBitmap(image, imageX, imageY, paint);
canvas.restore();

canvas.drawBitmap(image, imageX, imageY, null);

It is fast enough for a game frame animation, I've tested it.