Describing a collection

You can use the DescribeCollection operation to get the following information about a collection:

• The number of faces that are indexed into the collection.

• The version of the model being used with the collection. For more information, see Model versioning.

• The Amazon Resource Name (ARN) of the collection.

• The creation date and time of the collection.

To describe a collection (SDK)

1. If you haven't already:

   1. Create or update an IAM user with AmazonRekognitionFullAccess permissions. For more information, see Step 1: Set up an AWS account and create an IAM user.

   2. Install and configure the AWS CLI and the AWS SDKs. For more information, see Step 2: Set up the AWS CLI and AWS SDKs.

2. Use the following examples to call the DescribeCollection operation.

   Java

   This example describes a collection.

   Change the value collectionId to the ID of the desired collection.

   //Copyright 2018 Amazon.com, Inc. or its affiliates. All Rights Reserved.
   //PDX-License-Identifier: MIT-0 (For details, see https://github.com/awsdocs/amazon-rekognition-developer-guide/blob/master/LICENSE-SAMPLECODE.)
   
   package com.amazonaws.samples;
   
   import com.amazonaws.services.rekognition.AmazonRekognition;
   import com.amazonaws.services.rekognition.AmazonRekognitionClientBuilder;
   import com.amazonaws.services.rekognition.model.DescribeCollectionRequest;
   import com.amazonaws.services.rekognition.model.DescribeCollectionResult;
   
   
   public class DescribeCollection {
   
      public static void main(String[] args) throws Exception {
   
         String collectionId = "CollectionID";
         
         AmazonRekognition rekognitionClient = AmazonRekognitionClientBuilder.defaultClient();
   
               
         System.out.println("Describing collection: " +
            collectionId );
            
               
           DescribeCollectionRequest request = new DescribeCollectionRequest()
                       .withCollectionId(collectionId);
              
         DescribeCollectionResult describeCollectionResult = rekognitionClient.describeCollection(request); 
         System.out.println("Collection Arn : " +
            describeCollectionResult.getCollectionARN());
         System.out.println("Face count : " +
            describeCollectionResult.getFaceCount().toString());
         System.out.println("Face model version : " +
            describeCollectionResult.getFaceModelVersion());
         System.out.println("Created : " +
            describeCollectionResult.getCreationTimestamp().toString());
   
      } 
   
   }
       
   
   

   Java V2

   This code is taken from the AWS Documentation SDK examples GitHub repository. See the full example here.

       public static void describeColl(RekognitionClient rekClient, String collectionName) {
   
       try {
   
           DescribeCollectionRequest describeCollectionRequest = DescribeCollectionRequest.builder()
                .collectionId(collectionName)
                .build();
   
           DescribeCollectionResponse describeCollectionResponse = rekClient.describeCollection(describeCollectionRequest);
   
            System.out.println("Collection Arn : " +
                describeCollectionResponse.collectionARN());
            System.out.println("Created : " +
                describeCollectionResponse.creationTimestamp().toString());
   
       } catch(RekognitionException e) {
           System.out.println(e.getMessage());
           System.exit(1);
       }
      }
   

   AWS CLI

   This AWS CLI command displays the JSON output for the describe-collection CLI operation. Change the value of collection-id to the ID of the desired collection.

   aws rekognition describe-collection --collection-id collectionname 
                              

   Python

   This example describes a collection.

   Change the value collection_id to the ID of the desired collection.

   #Copyright 2018 Amazon.com, Inc. or its affiliates. All Rights Reserved.
   #PDX-License-Identifier: MIT-0 (For details, see https://github.com/awsdocs/amazon-rekognition-developer-guide/blob/master/LICENSE-SAMPLECODE.)
   
   import boto3
   from botocore.exceptions import ClientError
   
   def describe_collection(collection_id):
   
       print('Attempting to describe collection ' + collection_id)
       client=boto3.client('rekognition')
   
       try:
           response=client.describe_collection(CollectionId=collection_id)
           print("Collection Arn: "  + response['CollectionARN'])
           print("Face Count: "  + str(response['FaceCount']))
           print("Face Model Version: "  + response['FaceModelVersion'])
           print("Timestamp: "  + str(response['CreationTimestamp']))
   
           
       except ClientError as e:
           if e.response['Error']['Code'] == 'ResourceNotFoundException':
               print ('The collection ' + collection_id + ' was not found ')
           else:
               print ('Error other than Not Found occurred: ' + e.response['Error']['Message'])
       print('Done...')
   
   
   def main():
       collection_id='MyCollection'
       describe_collection(collection_id)
   
   if __name__ == "__main__":
       main()
   
   
   

   .NET

   This example describes a collection.

   Change the value collectionId to the ID of the desired collection.

   //Copyright 2018 Amazon.com, Inc. or its affiliates. All Rights Reserved.
   //PDX-License-Identifier: MIT-0 (For details, see https://github.com/awsdocs/amazon-rekognition-developer-guide/blob/master/LICENSE-SAMPLECODE.)
   
   using System;
   using Amazon.Rekognition;
   using Amazon.Rekognition.Model;
   
   public class DescribeCollection
   {
       public static void Example()
       {
           AmazonRekognitionClient rekognitionClient = new AmazonRekognitionClient();
   
           String collectionId = "CollectionID";
           Console.WriteLine("Describing collection: " + collectionId);
   
           DescribeCollectionRequest describeCollectionRequest = new DescribeCollectionRequest()
           {
               CollectionId = collectionId
           };
   
           DescribeCollectionResponse describeCollectionResponse = rekognitionClient.DescribeCollection(describeCollectionRequest);
           Console.WriteLine("Collection ARN: " + describeCollectionResponse.CollectionARN);
           Console.WriteLine("Face count: " + describeCollectionResponse.FaceCount);
           Console.WriteLine("Face model version: " + describeCollectionResponse.FaceModelVersion);
           Console.WriteLine("Created: " + describeCollectionResponse.CreationTimestamp);
       }
   }
   

   Node.js

   import { DescribeCollectionCommand } from  "@aws-sdk/client-rekognition";
   import  { RekognitionClient } from "@aws-sdk/client-rekognition";
   import { stringify } from "querystring";
   
   // Set the AWS Region.
   const REGION = "region"; //e.g. "us-east-1"
   const rekogClient = new RekognitionClient({ region: REGION });
   
   // Name the collection
   const collection_name = "collectionName"
   const resourceArn = "resourceArn"
   
   const describeCollection = async (collectionName) => {
       try {
          console.log(`Attempting to describe collection named - ${collectionName}`)
          var response = await rekogClient.send(new DescribeCollectionCommand({CollectionId: collectionName}))
          console.log('Collection Arn:')
          console.log(response.CollectionARN)
          console.log('Face Count:')
          console.log(response.FaceCount)
          console.log('Face Model Version:')
          console.log(response.FaceModelVersion)
          console.log('Timestamp:')
          console.log(response.CreationTimestamp)
          return response; // For unit tests.
       } catch (err) {
         console.log("Error", err.stack);
       }
     };
   
   describeCollection(collection_name)

DescribeCollection operation request

The input to DescribeCollection is the ID of the desired collection, as shown in the following JSON example.

{
    "CollectionId": "MyCollection"
}

DescribeCollection operation response

The response includes:

• The number of faces that are indexed into the collection, FaceCount.

• The version of the face model being used with the collection, FaceModelVersion. For more information, see Model versioning.

• The collection Amazon Resource Name, CollectionARN.

• The creation time and date of the collection, CreationTimestamp. The value of CreationTimestamp is the number of milliseconds since the Unix epoch time until the creation of the collection. The Unix epoch time is 00:00:00 Coordinated Universal Time (UTC), Thursday, 1 January 1970. For more information, see Unix Time.

{
    "CollectionARN": "arn:aws:rekognition:us-east-1:nnnnnnnnnnnn:collection/MyCollection",
    "CreationTimestamp": 1.533422155042E9,
    "FaceCount": 200,
    "FaceModelVersion": "1.0"
}