Using GPL library in our software [duplicate]

Question

This question already has answers here:

Can I use GPL software in a commercial application (4 answers)

Closed 6 years ago.

Currently we're starting to work on a project for which we're going to need image processing libraries. The problem is some of the libraries are GPL licensed.

I'm reading through GPL licence and quite a lot of other ones (FreeImage public licence etc..) and I'm a bit confused of all the long text. So I'll ask bluntly:

Is it possible to use a GPL licenced library in our commercial product (not modifying the code, just building the library and using it in our product (as a DLL)) without releasing the source code of our product?

Answer 1

Don't distribute

The GPL is primarily about distribution of your software (what they call "conveyance"). If you only use your app and the GPL library in-house, the GPL does not consider this conveyance, and the copyleft provision is not triggered. You therefore don't need to make your program open-source.

Communicate at arms length

If your program does not depend on the GPL library or application for its proper functioning, and you communicate at arms length with it through spawning a separate process, pipes or something similar rather than linking the library in your application directly, then the GPL considers your program a separate application (instead of a derived work), and you don't need to make your program open-source.