Copyright | (c) 2013-2021 Brendan Hay |
---|---|
License | Mozilla Public License, v. 2.0. |
Maintainer | Brendan Hay <brendan.g.hay+amazonka@gmail.com> |
Stability | auto-generated |
Portability | non-portable (GHC extensions) |
Safe Haskell | None |
Amazonka.Rekognition.SearchFacesByImage
Description
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.
To search for all faces in an input image, you might first call the IndexFaces operation, and then use the face IDs returned in subsequent calls to the SearchFaces operation.
You can also call the DetectFaces
operation and use the bounding boxes
in the response to make face crops, which then you can pass in to the
SearchFacesByImage
operation.
You pass the input image either as base64-encoded image bytes or as a reference to an image in an Amazon S3 bucket. If you use the AWS CLI to call Amazon Rekognition operations, passing image bytes is not supported. The image must be either a PNG or JPEG formatted file.
The response returns an array of faces that match, ordered by similarity
score with the highest similarity first. More specifically, it is an
array of metadata for each face match found. Along with the metadata,
the response also includes a similarity
indicating how similar the
face is to the input face. In the response, the operation also returns
the bounding box (and a confidence level that the bounding box contains
a face) of the face that Amazon Rekognition used for the input image.
If no faces are detected in the input image, SearchFacesByImage
returns an InvalidParameterException
error.
For an example, Searching for a Face Using an Image in the Amazon Rekognition Developer Guide.
The QualityFilter
input parameter allows you to filter out detected
faces that don’t meet a required quality bar. The quality bar is based
on a variety of common use cases. Use QualityFilter
to set the quality
bar for filtering by specifying LOW
, MEDIUM
, or HIGH
. If you do
not want to filter detected faces, specify NONE
. The default value is
NONE
.
To use quality filtering, you need a collection associated with version 3 of the face model or higher. To get the version of the face model associated with a collection, call DescribeCollection.
This operation requires permissions to perform the
rekognition:SearchFacesByImage
action.
Synopsis
- data SearchFacesByImage = SearchFacesByImage' {}
- newSearchFacesByImage :: Text -> Image -> SearchFacesByImage
- searchFacesByImage_qualityFilter :: Lens' SearchFacesByImage (Maybe QualityFilter)
- searchFacesByImage_faceMatchThreshold :: Lens' SearchFacesByImage (Maybe Double)
- searchFacesByImage_maxFaces :: Lens' SearchFacesByImage (Maybe Natural)
- searchFacesByImage_collectionId :: Lens' SearchFacesByImage Text
- searchFacesByImage_image :: Lens' SearchFacesByImage Image
- data SearchFacesByImageResponse = SearchFacesByImageResponse' {}
- newSearchFacesByImageResponse :: Int -> SearchFacesByImageResponse
- searchFacesByImageResponse_faceMatches :: Lens' SearchFacesByImageResponse (Maybe [FaceMatch])
- searchFacesByImageResponse_faceModelVersion :: Lens' SearchFacesByImageResponse (Maybe Text)
- searchFacesByImageResponse_searchedFaceBoundingBox :: Lens' SearchFacesByImageResponse (Maybe BoundingBox)
- searchFacesByImageResponse_searchedFaceConfidence :: Lens' SearchFacesByImageResponse (Maybe Double)
- searchFacesByImageResponse_httpStatus :: Lens' SearchFacesByImageResponse Int
Creating a Request
data SearchFacesByImage Source #
See: newSearchFacesByImage
smart constructor.
Constructors
SearchFacesByImage' | |
Fields
|
Instances
newSearchFacesByImage Source #
Arguments
:: Text | |
-> Image | |
-> SearchFacesByImage |
Create a value of SearchFacesByImage
with all optional fields omitted.
Use generic-lens or optics to modify other optional fields.
The following record fields are available, with the corresponding lenses provided for backwards compatibility:
$sel:qualityFilter:SearchFacesByImage'
, searchFacesByImage_qualityFilter
- A filter that specifies a quality bar for how much filtering is done to
identify faces. Filtered faces aren't searched for in the collection.
If you specify AUTO
, Amazon Rekognition chooses the quality bar. If
you specify LOW
, MEDIUM
, or HIGH
, filtering removes all faces that
don’t meet the chosen quality bar. The quality bar is based on a variety
of common use cases. Low-quality detections can occur for a number of
reasons. Some examples are an object that's misidentified as a face, a
face that's too blurry, or a face with a pose that's too extreme to
use. If you specify NONE
, no filtering is performed. The default value
is NONE
.
To use quality filtering, the collection you are using must be associated with version 3 of the face model or higher.
$sel:faceMatchThreshold:SearchFacesByImage'
, searchFacesByImage_faceMatchThreshold
- (Optional) Specifies the minimum confidence in the face match to return.
For example, don't return any matches where confidence in matches is
less than 70%. The default value is 80%.
$sel:maxFaces:SearchFacesByImage'
, searchFacesByImage_maxFaces
- Maximum number of faces to return. The operation returns the maximum
number of faces with the highest confidence in the match.
$sel:collectionId:SearchFacesByImage'
, searchFacesByImage_collectionId
- ID of the collection to search.
$sel:image:SearchFacesByImage'
, searchFacesByImage_image
- The input image as base64-encoded bytes or an S3 object. If you use the
AWS CLI to call Amazon Rekognition operations, passing base64-encoded
image bytes is not supported.
If you are using an AWS SDK to call Amazon Rekognition, you might not
need to base64-encode image bytes passed using the Bytes
field. For
more information, see Images in the Amazon Rekognition developer guide.
Request Lenses
searchFacesByImage_qualityFilter :: Lens' SearchFacesByImage (Maybe QualityFilter) Source #
A filter that specifies a quality bar for how much filtering is done to
identify faces. Filtered faces aren't searched for in the collection.
If you specify AUTO
, Amazon Rekognition chooses the quality bar. If
you specify LOW
, MEDIUM
, or HIGH
, filtering removes all faces that
don’t meet the chosen quality bar. The quality bar is based on a variety
of common use cases. Low-quality detections can occur for a number of
reasons. Some examples are an object that's misidentified as a face, a
face that's too blurry, or a face with a pose that's too extreme to
use. If you specify NONE
, no filtering is performed. The default value
is NONE
.
To use quality filtering, the collection you are using must be associated with version 3 of the face model or higher.
searchFacesByImage_faceMatchThreshold :: Lens' SearchFacesByImage (Maybe Double) Source #
(Optional) Specifies the minimum confidence in the face match to return. For example, don't return any matches where confidence in matches is less than 70%. The default value is 80%.
searchFacesByImage_maxFaces :: Lens' SearchFacesByImage (Maybe Natural) Source #
Maximum number of faces to return. The operation returns the maximum number of faces with the highest confidence in the match.
searchFacesByImage_collectionId :: Lens' SearchFacesByImage Text Source #
ID of the collection to search.
searchFacesByImage_image :: Lens' SearchFacesByImage Image Source #
The input image as base64-encoded bytes or an S3 object. If you use the AWS CLI to call Amazon Rekognition operations, passing base64-encoded image bytes is not supported.
If you are using an AWS SDK to call Amazon Rekognition, you might not
need to base64-encode image bytes passed using the Bytes
field. For
more information, see Images in the Amazon Rekognition developer guide.
Destructuring the Response
data SearchFacesByImageResponse Source #
See: newSearchFacesByImageResponse
smart constructor.
Constructors
SearchFacesByImageResponse' | |
Fields
|
Instances
newSearchFacesByImageResponse Source #
Create a value of SearchFacesByImageResponse
with all optional fields omitted.
Use generic-lens or optics to modify other optional fields.
The following record fields are available, with the corresponding lenses provided for backwards compatibility:
$sel:faceMatches:SearchFacesByImageResponse'
, searchFacesByImageResponse_faceMatches
- An array of faces that match the input face, along with the confidence
in the match.
$sel:faceModelVersion:SearchFacesByImageResponse'
, searchFacesByImageResponse_faceModelVersion
- Version number of the face detection model associated with the input
collection (CollectionId
).
$sel:searchedFaceBoundingBox:SearchFacesByImageResponse'
, searchFacesByImageResponse_searchedFaceBoundingBox
- The bounding box around the face in the input image that Amazon
Rekognition used for the search.
$sel:searchedFaceConfidence:SearchFacesByImageResponse'
, searchFacesByImageResponse_searchedFaceConfidence
- The level of confidence that the searchedFaceBoundingBox
, contains a
face.
$sel:httpStatus:SearchFacesByImageResponse'
, searchFacesByImageResponse_httpStatus
- The response's http status code.
Response Lenses
searchFacesByImageResponse_faceMatches :: Lens' SearchFacesByImageResponse (Maybe [FaceMatch]) Source #
An array of faces that match the input face, along with the confidence in the match.
searchFacesByImageResponse_faceModelVersion :: Lens' SearchFacesByImageResponse (Maybe Text) Source #
Version number of the face detection model associated with the input
collection (CollectionId
).
searchFacesByImageResponse_searchedFaceBoundingBox :: Lens' SearchFacesByImageResponse (Maybe BoundingBox) Source #
The bounding box around the face in the input image that Amazon Rekognition used for the search.
searchFacesByImageResponse_searchedFaceConfidence :: Lens' SearchFacesByImageResponse (Maybe Double) Source #
The level of confidence that the searchedFaceBoundingBox
, contains a
face.
searchFacesByImageResponse_httpStatus :: Lens' SearchFacesByImageResponse Int Source #
The response's http status code.