If you are using the RealSense SDK in Windows, you can use the QueryMirrorMode instruction to find out which orientation the image is in.
This instruction is categorized as being 'device neutral', meaning that it likely works with any RealSense camera model.
The orientation can be set with SetMirrorMode.
Below is an example C# script that demonstrates the use of SetMirrorMode (see the bottom of the script).
Thank you very much for your fast reply. I will check it over the weekend and will let you know