rectangle curve with rounded corners, tube, picture frame, howto

Hey there,

i am trying to find the easiest way to to a simple and variable picture frame like a tube.
The base should be a rectangle curve with rounded corners. I like to simply change aspects of the frame to try out different settings. For example the amount of rounding and the thickness of the frame.
What is the best way to create such a frame in blender without creating it vertex by vertex? Here are some images how it could look:



How can i do a rectangle curve without drawing it myself? I only can find circle curves.

I needed some time to find the extra tools menu :). but after finding it, it was really easy to do. thanks for the help.