Detecting Y-axis orientation for post-processing

The issue I am experiencing is that I am doing image processing which at the end of processing gives me x,y coordinates where I will subsequently draw certain elements (iteratively), so GPU acceleration does not make sense for that final step.

Unfortunately, I've noticed that on different hardware, the y-axis orientation varies. Is there a convenient way for me to discover this orientation?

I would use a two-pixel tall image with a black and a white pixel and start by determining the orientation but I wonder if there's a better solution or a feature addition to gpujs.