From: Timothy Hunter <cyclists@...>
Date: 2005-04-08T08:44:42+09:00
Subject: Re: RMagick question

Joe Van Dyk wrote:
> Hi,
> 
> I'd like to generate a thumbnail of an image.  The thumbnail should
> have curved corners (corners colored a specified color).  Any ideas on
> what functions I could use?
> 
> Thanks,
> Joe
> 
> 
Here's a script that adds transparent round corners.

require 'RMagick'
include Magick

hat = Image.read('Flower_Hat.jpg').first
hat.resize!(0.5)

mask = Image.new(hat.columns, hat.rows) {self.background_color = 'black'}
gc = Draw.new
gc.stroke('white').fill('white')
gc.roundrectangle(0, 0, hat.columns-1, hat.rows-1, 20, 20)
gc.draw(mask)

mask.matte = false
hat.matte = true

thumb = hat.composite(mask, CenterGravity, CopyOpacityCompositeOp)
thumb.display