How does Facial Recognition Work?

To explain the hows, we need to know what exactly we’re talking about. Let’s ask the crucial question:

What is facial recognition?

There are two main types of facial recognition. The one in your iPhone, called access control, uses your phone camera to project an IR light pattern onto your face. The camera captures the distortion of this pattern, creating a 3D depth map of your facial features, which is used to unlock your device.

The other is a facial recognition used by websites like lenso.ai. This page, in particular, finds faces using just a photo. It matches your face with faces found online, making it easy to see where your image was shared.

How does AI detect faces in photos? Simple Explanation

AI is often taught how to detect faces just like any other reverse image search - by machine learning. Simply said, the software learns how to recognize faces by being ‘fed’ images of different people. It can learn to recognize features like nose, eyes, mouth, and the distance between them. Then, it transfers images into vectors and compares them to see which images of faces are similar to each other.

Confused? Here’s a video that explains machine learning used in image search in simple terms:

The Basics of Facial Search - Detailed Description

Reverse image search tools work by using a system called Content-Based Image Retrieval (CBIR), which allows you to search using an image instead of typing a description. Instead of looking at text, the system focuses on visual elements like colors, shapes, and how pixels are arranged. It then extracts important features from the image and turns them into digital vectors.

To improve accuracy, these tools use deep learning - layered neural networks that learn to recognize complex features over time. When you submit an image, the system compares its features with those stored in a large index - something similar to a database, but it’s not a base of images - it’s an index of reference links to the images that were found online.

Facial recognition works in a similar way but focuses specifically on human faces. It creates a facial map by analyzing the shapes and distances between key features like the eyes, nose, and mouth. This map is also converted into a vector and compared with others in the database. If the vectors are close in value, it means the faces are likely a match.

Find your own face online with Facial Search

How to find your face online? Use lenso.ai Facial Search*.

You can upload your image here to find your face now:

Or find it using lenso.ai’s official website:

  1. Visit lenso’s website: lenso.ai.
  2. Upload a picture of your face.
  3. Make sure to choose the “People” tab.
  4. Click on the image that matches your search to be redirected to the website where it appeared.

Tip: Sign up for lenso’s automatic email alerts: whenever lenso.ai finds a match for your face, you'll receive a notification via email.

*Available in selected regions

Integrate Facial Recognition Into Your Application

Facial Recognition can be used in your own applications!

There are some online tutorials on how to build your own face recognition web app or Integrate Facial Recognition Technology in the Mobile App.

You can also take a look at available Face Search APIs and integrate them into your application to add the function of finding faces online from a photo. It’s like a reverse image search but for faces!

Lenso.ai’s Face Search API

To integrate lenso.ai with your application, visit our API page and follow the instructions given.

Security and Personal Safety in the Age of Facial Search

To remove your images from facial search engines, most of them offer an Opt-Out request. If a page only offers a Paid Opt-Out, it’s a scam - beware, these pages steal images from other sources, and they should never request money for removing your likeness.

Here are a few more tips: How to remove your image from the internet?.

Author

Kinga Jasinska

Marketing Specialist