3. Build your own face detection program with AI:

1.3. Introduction

Face detection is one of the techniques of artificial intelligence that allows computers to identify human faces in images or videos. The computer uses this technique to distinguish a human face from other elements in the image.

2.3. Applications of face detection:

Face detection has many real-world applications. For example, smartphones use it to unlock screens by recognizing the user’s face and blocking others. It is also used in entertainment, such as social media filters, where it detects the user's face and applies effects to parts like eyes, nose, and mouth. It's also used in security to identify thieves using surveillance cameras.

3.3. How face recognition technology works:

Face detection apps use algorithms and machine learning to find human faces in images that may include other objects like buildings or hands. These algorithms typically start by detecting the eyes, as they're the easiest to identify. Then, they try to detect the eyebrows, mouth, nose, and iris. Once a face is found, more tests confirm it. The face is then represented by a set of numbered key points to simplify programming.

4.3. Representing faces using points:

As previously mentioned, once a face is detected, its features are transformed into points, each with a number for easy access. The image above illustrates this process, showing how a face can be converted into numbered points.

5.3. Key points for analyzing facial features:

The image above shows the main points of the face and their corresponding numbers. We will use these points to program fun applications in future lessons. For instance, the point for the upper lip is (1), for the lower lip it's (17), and for the nose it’s (5). These numeric identifiers make it easier to analyze and develop applications using face data.