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ageitgey/face_recognition

56,407PythonAudience · developerComplexity · 2/5StaleLicenseSetup · moderate

TLDR

Python library that detects, identifies, and compares faces in images and video with just a few lines of code, no deep learning knowledge required.

Mindmap

mindmap
  root((face_recognition))
    What it does
      Detect faces
      Identify people
      Compare faces
      Extract landmarks
    How it works
      dlib models
      Face encoding
      Distance matching
      99.38% accuracy
    Use cases
      Attendance systems
      Security cameras
      Photo organization
      Access control
    Tech stack
      Python
      dlib
      cmake
    Getting started
      CLI tool included
      Few lines of code
      Pre-trained models

Things people build with this

USE CASE 1

Build an attendance system that automatically logs who enters a room by recognizing faces in a camera feed.

USE CASE 2

Organize a photo library by automatically grouping images of the same person together.

USE CASE 3

Create a security system that alerts you when a known person appears on a security camera.

USE CASE 4

Apply digital filters or effects to facial features by extracting precise landmark points from faces.

Tech stack

PythondlibcmakeNumPy

Getting it running

Difficulty · moderate Time to first run · 30min

dlib requires cmake and C++ compilation, which can be slow on first install depending on system.

Use freely for any purpose, including commercial use, as long as you keep the copyright notice.

In plain English

Face Recognition is a Python library that makes it straightforward to find, identify, and compare human faces in images and video. The goal is to give developers the simplest possible interface for facial recognition tasks without needing to understand the underlying deep learning machinery. The library solves a practical problem: facial recognition is technically complex, normally requiring knowledge of convolutional neural networks, computer vision pipelines, and model training. This library wraps all of that complexity so you can detect, identify, and compare faces in just a few lines of code. How it works under the hood: the library is built on top of dlib, a C++ machine learning library with pre-trained deep learning models. When you pass an image to the library, it first locates faces in the image by finding the characteristic patterns of eyes, nose, and mouth. Then it generates a numerical "encoding", a fixed-length list of 128 numbers, that represents each face in a way that is stable across different photos of the same person. To recognize a person, you compare their encoding against a set of known encodings; if the distance between them is small enough, it's a match. This approach achieves 99.38% accuracy on the standard Labeled Faces in the Wild benchmark. You can also extract facial landmark points, the precise locations of eyes, eyebrows, nose, lips, and chin, for more detailed work like applying digital filters. You would use this library for building attendance systems, security camera analysis, photo organization by person, or any application that needs to answer "who is in this image?" The tech stack is Python, with dlib and cmake as dependencies, and it also includes a command-line tool for batch processing folders of images without writing any code.

Copy-paste prompts

Prompt 1
Show me how to load an image and detect all faces in it using face_recognition, then print the number of faces found.
Prompt 2
How do I compare two photos to see if they contain the same person using face_recognition? Give me a working example.
Prompt 3
Write a Python script using face_recognition that takes a folder of known people's photos and then identifies who appears in a new photo.
Prompt 4
How do I extract facial landmarks (eyes, nose, mouth, chin) from a face in an image using face_recognition?
Prompt 5
Show me how to use the face_recognition command-line tool to batch process a folder of images without writing Python code.
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Generated 2026-05-18 · Model: sonnet-4-6 · Verify against the repo before relying on details.