How to make rounded corners to a mask with scripts?

[SixToF]

Is there a way to give an image rouned corners?
Here is an example of two images with desired outcome.

I've searched in Official Scripting Guide. Coudn't find anything.

[Mylenium]

What does any of this have to do with scripting? Scripts don't do any pixcxel processing. You'd have to write a custom plug-in. Still, why not simply use a shape layer and apply it as a track matte? I think you need to start by actual learning AE at the most basic level before venturing any further. Your question alone to me implies that you have a completely wrong understanding of what AE does and how it works.

Mylenium

[SixToF]

Oh, thank you for your honesty, and a quick reply. You are correct, I'm complete and utter noob in AE. Infact, some people might consider me and idiot. I apologise for asking an extremely stupid question. Fo some reason I thought that asking a question is a way of learning basics. But still, I thank you for your warm reply.

If I may, I would like to say that perhaps, some people might take my question too directly. As it is known that AE is not a Photoshop, and if some one seeks image edition he might want to use the letter. So since I know all that, and I still ask and formulate my question the way I did. Does that mean I expect other ideas.

My initial idea was to create a mask with rounded corners. I'd did create a mask, but with sharp corners. On my attempt to access roundness property AE returns an error.

[SixToF]

My main problem is that I don't know how to access Roundness property of Shape layer. So I could set track matte.
Or if I deside to go with the mask, how to set it's rounded properties.