How to make(edit) .ICO file for compiler (QT)?

Question

Graphic arts

Hello.
I'm editing the source code of the program (compiled using QT) and I need to slightly improve the appearance - and there are icons in the .ICO format - I opened them through GIMP (specially installed) - and inside I found that there are many sizes of this picture, nested like a nested doll)) ( please don’t laugh, this is the first time I’m doing this - this is new for me) and I have a question:
- In which program should I edit or create this nesting doll icon?
I usually work with graphics in Fireworks (I'm not a freak, I just got used to it a long time ago, it's convenient), but Fireworks does not understand the ICO format. I don't know how to work with GIMP. Is there something very simple to change the logo in this .ico file?
Thank you.

Answer 1

Quietly I am talking to myself ...
The solution was unexpected: it's easier to do it in Ubuntu and not in Windows using the imagemagic utility, for example. like this:
convert logo.png -define icon:auto-resize=64,48,32,16 logo.ico
Voila! ^^