The deep learning Santa/Not Santa detector

Did you see Mommy kissing Santa Claus? Or was it simply an imposter? The Not Santa detector is here to help solve the mystery once and for all.

Building a “Not Santa” detector on the Raspberry Pi using deep learning, Keras, and Python

The video is a demo of my “Not Santa” detector that I deployed to the Raspberry Pi. I trained the detector using deep learning, Keras, and Python. You can find the full source code and tutorial here: https://www.pyimagesearch.com/2017/12/18/keras-deep-learning-raspberry-pi/

Ho-ho-how does it work?

Note: Adrian Rosebrock is not Santa. But he does a good enough impression of the jolly old fellow that his disguise can fool a Raspberry Pi into thinking otherwise.

Raspberry Pi 'Not Santa' detector

We jest, but has anyone seen Adrian and Santa in the same room together?
Image c/o Adrian Rosebrock

But how is the Raspberry Pi able to detect the Santa-ness or Not-Santa-ness of people who walk into the frame?

Two words: deep learning

If you’re not sure what deep learning is, you’re not alone. It’s a hefty topic, and one that Adrian has written a book about, so I grilled him for a bluffers’ guide. In his words, deep learning is:

…a subfield of machine learning, which is, in turn a subfield of artificial intelligence (AI). While AI embodies a large, diverse set of techniques and algorithms related to automatic reasoning (inference, planning, heuristics, etc), the machine learning subfields are specifically interested in pattern recognition and learning from data.

Artificial Neural Networks (ANNs) are a class of machine learning algorithms that can learn from data. We have been using ANNs successfully for over 60 years, but something special happened in the past 5 years — (1) we’ve been able to accumulate massive datasets, orders of magnitude larger than previous datasets, and (2) we have access to specialized hardware to train networks faster (i.e., GPUs).

Given these large datasets and specialized hardware, deeper neural networks can be trained, leading to the term “deep learning”.

So now we have a bird’s-eye view of deep learning, how does the detector detect?

Cameras and twinkly lights

Adrian used a model he had trained on two datasets to detect whether or not an image contains Santa. He deployed the Not Santa detector code to a Raspberry Pi, then attached a camera, speakers, and The Pi Hut’s 3D Xmas Tree.

Raspberry Pi 'Not Santa' detector

Components for Santa detection
Image c/o Adrian Rosebrock

The camera captures footage of Santa in the wild, while the Christmas tree add-on provides a twinkly notification, accompanied by a resonant ho, ho, ho from the speakers.

A deeper deep dive into deep learning

A full breakdown of the project and the workings of the Not Santa detector can be found on Adrian’s blog, PyImageSearch, which includes links to other deep learning and image classification tutorials using TensorFlow and Keras. It’s an excellent place to start if you’d like to understand more about deep learning.

Build your own Santa detector

Santa might catch on to Adrian’s clever detector and start avoiding the camera, and for that eventuality, we have our own Santa detector. It uses motion detection to notify you of his presence (and your presents!).

Raspberry Pi Santa detector

Check out our Santa Detector resource here and use a passive infrared sensor, Raspberry Pi, and Scratch to catch the big man in action.