GetLabelDetection
Gets the label detection results of a Amazon Rekognition Video analysis started by StartLabelDetection.
The label detection operation is started by a call to StartLabelDetection which returns a job identifier (JobId
). When
the label detection operation finishes, Amazon Rekognition publishes a completion status to the
Amazon Simple Notification Service topic registered in the initial call to StartlabelDetection
.
To get the results of the label detection operation, first check that the status value
published to the Amazon SNS topic is SUCCEEDED
. If so, call GetLabelDetection and pass the job identifier (JobId
) from the
initial call to StartLabelDetection
.
GetLabelDetection
returns an array of detected labels
(Labels
) sorted by the time the labels were detected. You can also sort by the
label name by specifying NAME
for the SortBy
input parameter. If
there is no NAME
specified, the default sort is by
timestamp.
You can select how results are aggregated by using the AggregateBy
input
parameter. The default aggregation method is TIMESTAMPS
. You can also aggregate
by SEGMENTS
, which aggregates all instances of labels detected in a given
segment.
The returned Labels array may include the following attributes:
-
Name - The name of the detected label.
-
Confidence - The level of confidence in the label assigned to a detected object.
-
Parents - The ancestor labels for a detected label. GetLabelDetection returns a hierarchical taxonomy of detected labels. For example, a detected car might be assigned the label car. The label car has two parent labels: Vehicle (its parent) and Transportation (its grandparent). The response includes the all ancestors for a label, where every ancestor is a unique label. In the previous example, Car, Vehicle, and Transportation are returned as unique labels in the response.
-
Aliases - Possible Aliases for the label.
-
Categories - The label categories that the detected label belongs to.
-
BoundingBox — Bounding boxes are described for all instances of detected common object labels, returned in an array of Instance objects. An Instance object contains a BoundingBox object, describing the location of the label on the input image. It also includes the confidence for the accuracy of the detected bounding box.
-
Timestamp - Time, in milliseconds from the start of the video, that the label was detected. For aggregation by
SEGMENTS
, theStartTimestampMillis
,EndTimestampMillis
, andDurationMillis
structures are what define a segment. Although the “Timestamp” structure is still returned with each label, its value is set to be the same asStartTimestampMillis
.
Timestamp and Bounding box information are returned for detected Instances, only if
aggregation is done by TIMESTAMPS
. If aggregating by SEGMENTS
,
information about detected instances isn’t returned.
The version of the label model used for the detection is also returned.
Note DominantColors
isn't returned for Instances
,
although it is shown as part of the response in the sample seen below.
Use MaxResults
parameter to limit the number of labels returned. If
there are more results than specified in MaxResults
, the value of
NextToken
in the operation response contains a pagination token for getting the
next set of results. To get the next page of results, call GetlabelDetection
and
populate the NextToken
request parameter with the token value returned from the
previous call to GetLabelDetection
.
If you are retrieving results while using the Amazon Simple Notification Service, note that you will receive an "ERROR" notification if the job encounters an issue.
Request Syntax
{
"AggregateBy": "string
",
"JobId": "string
",
"MaxResults": number
,
"NextToken": "string
",
"SortBy": "string
"
}
Request Parameters
For information about the parameters that are common to all actions, see Common Parameters.
The request accepts the following data in JSON format.
- AggregateBy
-
Defines how to aggregate the returned results. Results can be aggregated by timestamps or segments.
Type: String
Valid Values:
TIMESTAMPS | SEGMENTS
Required: No
- JobId
-
Job identifier for the label detection operation for which you want results returned. You get the job identifer from an initial call to
StartlabelDetection
.Type: String
Length Constraints: Minimum length of 1. Maximum length of 64.
Pattern:
^[a-zA-Z0-9-_]+$
Required: Yes
- MaxResults
-
Maximum number of results to return per paginated call. The largest value you can specify is 1000. If you specify a value greater than 1000, a maximum of 1000 results is returned. The default value is 1000.
Type: Integer
Valid Range: Minimum value of 1.
Required: No
- NextToken
-
If the previous response was incomplete (because there are more labels to retrieve), Amazon Rekognition Video returns a pagination token in the response. You can use this pagination token to retrieve the next set of labels.
Type: String
Length Constraints: Maximum length of 255.
Required: No
- SortBy
-
Sort to use for elements in the
Labels
array. UseTIMESTAMP
to sort array elements by the time labels are detected. UseNAME
to alphabetically group elements for a label together. Within each label group, the array element are sorted by detection confidence. The default sort is byTIMESTAMP
.Type: String
Valid Values:
NAME | TIMESTAMP
Required: No
Response Syntax
{
"GetRequestMetadata": {
"AggregateBy": "string",
"SortBy": "string"
},
"JobId": "string",
"JobStatus": "string",
"JobTag": "string",
"LabelModelVersion": "string",
"Labels": [
{
"DurationMillis": number,
"EndTimestampMillis": number,
"Label": {
"Aliases": [
{
"Name": "string"
}
],
"Categories": [
{
"Name": "string"
}
],
"Confidence": number,
"Instances": [
{
"BoundingBox": {
"Height": number,
"Left": number,
"Top": number,
"Width": number
},
"Confidence": number,
"DominantColors": [
{
"Blue": number,
"CSSColor": "string",
"Green": number,
"HexCode": "string",
"PixelPercent": number,
"Red": number,
"SimplifiedColor": "string"
}
]
}
],
"Name": "string",
"Parents": [
{
"Name": "string"
}
]
},
"StartTimestampMillis": number,
"Timestamp": number
}
],
"NextToken": "string",
"StatusMessage": "string",
"Video": {
"S3Object": {
"Bucket": "string",
"Name": "string",
"Version": "string"
}
},
"VideoMetadata": {
"Codec": "string",
"ColorRange": "string",
"DurationMillis": number,
"Format": "string",
"FrameHeight": number,
"FrameRate": number,
"FrameWidth": number
}
}
Response Elements
If the action is successful, the service sends back an HTTP 200 response.
The following data is returned in JSON format by the service.
- GetRequestMetadata
-
Information about the paramters used when getting a response. Includes information on aggregation and sorting methods.
Type: GetLabelDetectionRequestMetadata object
- JobId
-
Job identifier for the label detection operation for which you want to obtain results. The job identifer is returned by an initial call to StartLabelDetection.
Type: String
Length Constraints: Minimum length of 1. Maximum length of 64.
Pattern:
^[a-zA-Z0-9-_]+$
- JobStatus
-
The current status of the label detection job.
Type: String
Valid Values:
IN_PROGRESS | SUCCEEDED | FAILED
- JobTag
-
A job identifier specified in the call to StartLabelDetection and returned in the job completion notification sent to your Amazon Simple Notification Service topic.
Type: String
Length Constraints: Minimum length of 1. Maximum length of 1024.
Pattern:
[a-zA-Z0-9_.\-:+=\/]+
- LabelModelVersion
-
Version number of the label detection model that was used to detect labels.
Type: String
- Labels
-
An array of labels detected in the video. Each element contains the detected label and the time, in milliseconds from the start of the video, that the label was detected.
Type: Array of LabelDetection objects
- NextToken
-
If the response is truncated, Amazon Rekognition Video returns this token that you can use in the subsequent request to retrieve the next set of labels.
Type: String
Length Constraints: Maximum length of 255.
- StatusMessage
-
If the job fails,
StatusMessage
provides a descriptive error message.Type: String
- Video
-
Video file stored in an Amazon S3 bucket. Amazon Rekognition video start operations such as StartLabelDetection use
Video
to specify a video for analysis. The supported file formats are .mp4, .mov and .avi.Type: Video object
- VideoMetadata
-
Information about a video that Amazon Rekognition Video analyzed.
Videometadata
is returned in every page of paginated responses from a Amazon Rekognition video operation.Type: VideoMetadata object
Errors
For information about the errors that are common to all actions, see Common Errors.
- AccessDeniedException
-
You are not authorized to perform the action.
HTTP Status Code: 400
- InternalServerError
-
Amazon Rekognition experienced a service issue. Try your call again.
HTTP Status Code: 500
- InvalidPaginationTokenException
-
Pagination token in the request is not valid.
HTTP Status Code: 400
- InvalidParameterException
-
Input parameter violated a constraint. Validate your parameter before calling the API operation again.
HTTP Status Code: 400
- ProvisionedThroughputExceededException
-
The number of requests exceeded your throughput limit. If you want to increase this limit, contact Amazon Rekognition.
HTTP Status Code: 400
- ResourceNotFoundException
-
The resource specified in the request cannot be found.
HTTP Status Code: 400
- ThrottlingException
-
Amazon Rekognition is temporarily unable to process the request. Try your call again.
HTTP Status Code: 500
See Also
For more information about using this API in one of the language-specific AWS SDKs, see the following: