Diving deep into the Face API

The Face API has two main features. The first one is face detection and the other is face recognition.

Face detection allows us to detect up to 64 faces in one image. We have already seen the basic usage. The features of face recognition are implied in its name: using it, we can detect whether two faces belong to the same person. We can find similar faces, or one in particular, and we can group similar faces. We will learn how to do all of this in the following sections.

When calling any of the APIs, it will respond with one of the following responses:

Code	Description
200	Successful call. It returns an array containing data related to the API call.
400	Request body is invalid. This can be a number of errors, depending on the API call. Typically, the request code is invalid.
401	Access denied because of an invalid subscription key. The key may be wrong or the account/subscription plan may be blocked.
403	Out of call volume data. You have made...