Pan Tilt HAT not tracking real faces just photos?

I have my Pan Tilt HAT all setup on my Raspi Zero W and it works tracking photos of peoples faces but when I put my mug (or my colleagues) in the frame it doesn’t “recognize” the face as a face in that no square is drawn and the servos don’t move. I have tried both facetracker_haar.py and facetracker_lbp.py but both seem to ignore real faces! Is it lighting or the background or…?

It’s probably lighting. The recognition is incredibly crude if I’m not mistaken- recognising shadow under the eyes and down the edges of the nose, and a highlight on the bridge of the nose. Honestly, though, this is about the limit of my knowledge with facial recognition on the Pi. But perhaps someone here will be able to help.

I have been able to sketch crude lines on white paper with black ink and have those recognised. It also recognised a Freddo Frog…

Thanks, I will try in an area with better lighting.

As for “Freddo Frog” I did wonder if this was a special Sheffield delicacy as I hadn’t heard of that before but thanks to Google I now know it is a chocolate bar. :)