How to convert PDF to PNG using DMagick?

[tastyminerals]

When I need to convert a PDF image in console, I use ImageMagick: 
`convert doc.pdf doc.png` command. Today I found ImageMagick D 
bindings -- DMagick https://github.com/MikeWey/DMagick. I would 
like to script this operation using DMagick. However, I couldn't 
find any code samples and was not able to find anything about 
image conversion in official ImageMagick C API docs either (maybe 
I need to spend more time though). But maybe someone has code 
samples of how to convert PDF?