Obtain face id of an image and search for it in a collection with aws recognition

Question

I have the following problem, in a company they register with facial recognition and these faces are indexed in a collection of AWS Rekognition, there are often events and to speed up the registration of the event they want to take a single photo and have it recognize the faces and search for them in the collection and record the event attendance of each person etc, etc, ect.

const { FaceDetails } = await this.rekognition.detectFaces({
                Image: {
                    Bytes: imageBuffer
                }
            });

The problem with this code is that if it detects all the faces but does not give me the IDs of the faces, how can I get the ID of the face and see if it is in the collection? or what strategy should I follow?

The code only returns the attributes and information of the faces, but I don't know how to get something to help me search the collection

Answer 1

According to the DetectFaces documentation:

DetectFaces detects the 100 largest faces in the image. For each face detected, the operation returns face details. These details include a bounding box of the face, a confidence value (that the bounding box contains a face), and a fixed set of attributes such as facial landmarks (for example, coordinates of eye and mouth), pose, presence of facial occlusion, and so on.

You will notice that there is no mention of Face Collections for this API call.

Instead, if you want to find a face in a Face Collection, you should use SearchFacesByImage:

For a given input image, first detects the largest face in the image, and then searches the specified collection for matching faces. The operation compares the features of the input face with faces in the specified collection.