Horses Read Emotion from Photos

I have been showing Blessi the video of my grandniece MacKenzie playing her saxaphone.  Researchers showed horses a photo of a person who was happy or scowling.  Later the horses met those people in person.  Not only did the horses recognize the person from her photo but they showed signs of stress if the photo showed the person as angry.

So Blessi will recognize Kenzie but what will he think about her saxophone playing?

Here's a link to a great study. 
Beware the long face: horses remember your mood