If you're looking for a quick, simple way to do it, you can go to:
Click 'Choose file' and pick the file you want converted. Then click the 'Encode' button.
The encoded version of the file then appears in the Encoded Output pane. Save all of that text to a file, giving it whatever file name and extension you want).
The blog post you commented on gives more detail on how to write a program to do this, if you're interested.
Hope this helps,
Geoff