listFaces method
Returns metadata for faces in the specified collection. This metadata includes information such as the bounding box coordinates, the confidence (that the bounding box contains a face), and face ID. For an example, see Listing Faces in a Collection in the Amazon Rekognition Developer Guide.
This operation requires permissions to perform the
rekognition:ListFaces action.
May throw AccessDeniedException.
May throw InternalServerError.
May throw InvalidPaginationTokenException.
May throw InvalidParameterException.
May throw ProvisionedThroughputExceededException.
May throw ResourceNotFoundException.
May throw ThrottlingException.
Parameter collectionId :
ID of the collection from which to list the faces.
Parameter faceIds :
An array of face IDs to filter results with when listing faces in a
collection.
Parameter maxResults :
Maximum number of faces to return.
Parameter nextToken :
If the previous response was incomplete (because there is more data to
retrieve), Amazon Rekognition returns a pagination token in the response.
You can use this pagination token to retrieve the next set of faces.
Parameter userId :
An array of user IDs to filter results with when listing faces in a
collection.
Implementation
Future<ListFacesResponse> listFaces({
required String collectionId,
List<String>? faceIds,
int? maxResults,
String? nextToken,
String? userId,
}) async {
_s.validateNumRange(
'maxResults',
maxResults,
0,
4096,
);
final headers = <String, String>{
'Content-Type': 'application/x-amz-json-1.1',
'X-Amz-Target': 'RekognitionService.ListFaces'
};
final jsonResponse = await _protocol.send(
method: 'POST',
requestUri: '/',
exceptionFnMap: _exceptionFns,
// TODO queryParams
headers: headers,
payload: {
'CollectionId': collectionId,
if (faceIds != null) 'FaceIds': faceIds,
if (maxResults != null) 'MaxResults': maxResults,
if (nextToken != null) 'NextToken': nextToken,
if (userId != null) 'UserId': userId,
},
);
return ListFacesResponse.fromJson(jsonResponse.body);
}