How to determine the orientation of a video?

Question

Video processing

I need to determine the orientation of the video, for this I did this: I took the rotation variable from the video metadata, and if it is 0 or 180, then the video is horizontal, otherwise it is vertical, but the problem is that, for example, a vertical video downloaded from Instagram has the value of the variable rotation is 0. Based on this, I think that determining the orientation of the video from the value of the rotation variable is not the best option. How then correctly to define orientation?