(Note: I didn't know how to properly word this question: improvements are welcome!)
I'm looking for an utility (whether desktop or online service) to create folder icons in the same way as Windows 7 does in Explorer.
I guess it is just easier to show it than describe it:
I mean: if one creates a folder and it only puts a picture file inside, then Explorer will change icon for that folder, showing the picture as if inserted between the two folds.
At the moment, I'm able to do something similar, starting from a GIMP document with distinct layers for both folds and their content, for each icon size.
Is there any tool available where you can just provide a picture, and it will be able to create folder icons for each size as Explorer does?
EDIT (after comments):
I'd like to obtain the same results with a tool, so that I can save results as an .ICO file, associate that with the folder, and be free to store what I want in that folder root.