OpenCV (C++) stitcher not writing to OutputArray

I'm currently playing around with a 360° camera and want to use OpenCV's spherical warper for that. However, each time I try to run a simple program that makes use of the stitcher functionality, it fails to return a stitched image. I'm basically just taking the 360° picture, divide it into two separate pictures (front- and rear lens) and want to stitch them back together.I'm currently playing around with a 360° camera