3d – Rotation according to the global axis c ++ Quaternion

I'm trying to rotate a camera in C ++ but all I've been able to do is rotate the object itself or rotate the camera around it. object, I can not understand it. What I want is to rotate the camera on itself without moving it.

For example to turn left, I did this:

camera.orientation = (Quaternion(1 direction({0, -1,0})) * camera.orientation) .to_norm ();

where camera.orientation is a quaternion and 1 is the angle.

I guess I'm using a local axis instead of a global axis? How to convert?

Thank you