title: How to add a background color to drawn text
body: <p>Using ImageMagick 6.8.1, my goal is to add text to the bottom left corner of an image and to have that text's background be black. Essentially, I want something like a 20x20 black area in the bottom left corner of my image and that black area to have some text. I've gotten everything figured out except for the black background portion.</p>
  
  <p>This is what I have so far: 
  <code>convert in.tif -pointsize 10 -background "#000000" -fill white -gravity SouthWest -draw "text 0,0 'a'" out.tif)</code></p>