Dynamics Text

Adding text to moving images?
I'm going to a website where users can customize logos, business cards, etc. To do this we need a mechanism to add dynamic text from text boxes that the user will fill and the text should appear in the image of those selected. I use Ruby on Rails on the road. What suggestions on how I could do. Greetings thank you mate. ImageMagick seems to be consistent with Ruby on Rails (RMagick). I will consider this. Even if I can customize the images in real time, so it's good. Other points to be added to ImageMagick?
Most sites include graphics for the half. What I did was make things simple on the command line I can create a CGI script in the routine. But his frustration for me to try anything too luxurious











