SearchFaces

Last updated: 2021-01-18 14:23:49

1. API Description

Domain name for API request: iai.tencentcloudapi.com.

This API is used to recognize top K persons in one or more groups who are similar to the person in a given image and rank the similarity in a descending order.

Up to 10 faces in an image can be recognized at a time, and up to 100 groups can be searched in at a time.

The maximum number of faces in groups that can be searched for at a time is subject to the group's algorithm model version (FaceModelVersion), which is 1 million for v2.0 or 3 million for v3.0.

This API recognizes each face image of a person as an independent one. By contrast, the SearchPersons and SearchPersonsReturnsByGroup APIs fuse the features of all face images of a person; for example, if a person has 4 face images, they will fuse the features of the 4 face images and generate the summarized facial features of the person to make the search more accurate.

This API should be used together with Group Management APIs.

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2. Input Parameters

The following request parameter list only provides API request parameters and some common parameters. For the complete common parameter list, see Common Request Parameters.

Parameter Name Required Type Description
Action Yes String Common parameter. The value used for this API: SearchFaces.
Version Yes String Common parameter. The value used for this API: 2020-03-03.
Region Yes String Common parameter. For more information, please see the list of regions supported by the product.
GroupIds.N Yes Array of String List of groups to be searched in (up to 100). The array element value is the GroupId in the CreateGroup API.
Image No String Base64-encoded image data, which cannot exceed 5 MB.
The long side cannot exceed 4,000 px for images in JPG format or 2,000 px for images in other formats.
PNG, JPG, JPEG, and BMP images are supported, while GIF images are not.
Url No String Image URL. The image cannot exceed 5 MB in size after being Base64-encoded.
The long side cannot exceed 4,000 px for images in JPG format or 2,000 px for images in other formats.
Either Url or Image must be provided; if both are provided, only Url will be used.
We recommend storing the image in Tencent Cloud, as a Tencent Cloud URL can guarantee higher download speed and stability.
The download speed and stability of non-Tencent Cloud URLs may be low.
PNG, JPG, JPEG, and BMP images are supported, while GIF images are not.
MaxFaceNum No Integer Maximum number of recognizable faces. Default value: 1 (i.e., detecting only the face with the largest size in the image). Maximum value: 10.
MaxFaceNum is used to control the number of faces to be searched for if there are multiple faces in the input image to be recognized.
For example, if the input image in Image or Url contains multiple faces and MaxFaceNum is 5, top 5 faces with the largest size in the image will be recognized.
MinFaceSize No Integer Minimum height and width of face in px. Default value: 34. Face images whose value is below 34 cannot be recognized. We recommend setting this parameter to 80.
MaxPersonNum No Integer Number of the most similar persons returned for one single recognized face image. Default value: 5. Maximum value: 100.
For example, if MaxFaceNum is 1 and MaxPersonNum is 8, information of the top 8 most similar persons will be returned.
The greater the value, the longer the processing time. We recommend setting a value below 10.
NeedPersonInfo No Integer Whether to return person details. 0: no; 1: yes. Default value: 0. Other values will be considered as 0 by default.
QualityControl No Integer Image quality control.
0: no control.
1: low quality requirement. The image has one or more of the following problems: extreme blurriness, covered eyes, covered nose, and covered mouth.
2: average quality requirement. The image has at least three of the following problems: excessive brightness, excessive dimness, blurriness or average blurriness, covered eyebrows, covered cheeks, and covered chin.
3: high-quality requirement. The image has one to two of the following problems: excessive brightness, excessive dimness, average blurriness, covered eyebrows, covered cheeks, and covered chin.
4: very high-quality requirement. The image is optimal in all dimensions or only has a slight problem in one dimension.
Default value: 0.
If the image quality does not meet the requirement, the returned result will prompt that the detected image quality is unsatisfactory.
FaceMatchThreshold No Float In the output parameter Score, the result will be returned only if the result value is above the FaceMatchThreshold value. Default value: 0.
NeedRotateDetection No Integer Whether to enable the support for rotated image recognition. 0: no; 1: yes. Default value: 0. When the face in the image is rotated and the image has no EXIF information, if this parameter is not enabled, the face in the image cannot be correctly detected and recognized. If you are sure that the input image contains EXIF information or the face in the image will not be rotated, do not enable this parameter, as the overall time consumption may increase by hundreds of milliseconds after it is enabled.

3. Output Parameters

Parameter Name Type Description
Results Array of Result Recognition result.
FaceNum Integer Number of faces included in searched groups.
FaceModelVersion String Algorithm model version used for face recognition.
RequestId String The unique request ID, which is returned for each request. RequestId is required for locating a problem.

4. Example

Example1 Searching for face

Input Example

https://iai.tencentcloudapi.com/?Action=SearchFaces
&Url=http://test.image.myqcloud.com/testA.jpg
&MaxFaceNum=1
&MinFaceSize=40
&MaxPersonNum=5
&GroupIds.0=TencentShenZhenEmployee
&<Common request parameters>

Output Example

{
  "Response": {
    "Results": [
      {
        "RetCode": 0,
        "Candidates": [
          {
            "PersonId": "1001",
            "FaceId": "2875093635484912302",
            "PersonName": "Jerry",
            "Gender": 0,
            "Score": 100,
            "PersonGroupInfos": [
              {
                "GroupId": "abc",
                "PersonExDescriptions": [
                  "description1",
                  "description2"
                ]
              }
            ]
          }
        ],
        "FaceRect": {
          "X": 370,
          "Y": 46,
          "Width": 75,
          "Height": 75
        }
      }
    ],
    "FaceNum": 1,
    "FaceModelVersion": "3.0",
    "RequestId": "57b42b73-b978-45b9-8095-8f50e9642d35"
  }
}

Example2 Sample error

This example shows the error that will occur if the MaxFaceNum is greater than 10.

Input Example

https://iai.tencentcloudapi.com/?Action=SearchFaces
&Url=http://test.image.myqcloud.com/testA.jpg
&MaxFaceNum=11
&GroupIds.0=TencentShenZhenEmployee
&<Common request parameters>

Output Example

{
  "Response": {
    "Error": {
      "Code": "FailedOperation.SearchFacesExceed",
      "Message": "The number of faces searched for exceeded the limit."
    },
    "RequestId": "f04ba2f3-532c-4207-9caa-6e818ded7fb9"
  }
}

Example3 Sample error - 2

This example shows the error that will occur if an image URL is incorrect.

Input Example

https://iai.tencentcloudapi.com/?Action=SearchFaces
&Url=http://test.image.myqcloud.com/testA
&GroupIds.0=TencentShenZhenEmployee
&<Common request parameters>

Output Example

{
  "Response": {
    "Error": {
      "Code": "FailedOperation.ImageDownloadError",
      "Message": "An error occurred while downloading the image."
    },
    "RequestId": "527ecffe-4c6a-47c9-8217-4dd2e3f018da"
  }
}

5. Developer Resources

SDK

TencentCloud API 3.0 integrates SDKs that support various programming languages to make it easier for you to call APIs.

Command Line Interface

6. Error Code

The following only lists the error codes related to the API business logic. For other error codes, see Common Error Codes.

Error Code Description
FailedOperation.AcrossVersionsError This operation cannot be performed across algorithm model versions.
FailedOperation.ConflictOperation The operations conflict. Do not operate on the same person simultaneously.
FailedOperation.DuplicatedGroupDescription The custom description field must be unique in the group.
FailedOperation.FaceSizeTooSmall The face frame size is smaller than the MinFaceSize value, and the face is filtered out.
FailedOperation.GroupInDeletedState The current group is being deleted. Please wait.
FailedOperation.GroupPersonMapExist The ID of the corresponding person is already in the group.
FailedOperation.GroupPersonMapNotExist The ID of the corresponding person is not in the group.
FailedOperation.ImageDecodeFailed Image decoding failed.
FailedOperation.ImageDownloadError An error occurred while downloading the image.
FailedOperation.ImageFacedetectFailed Face detection failed.
FailedOperation.ImageResolutionExceed The image resolution is too high.
FailedOperation.ImageResolutionTooSmall The image short edge resolution is smaller than 64.
FailedOperation.ImageSizeExceed The size of the Base64-encoded image cannot exceed 5 MB.
FailedOperation.RequestLimitExceeded The request frequency exceeds the limit.
FailedOperation.RequestTimeout The backend service timed out.
FailedOperation.SearchFacesExceed The number of faces searched for exceeds the limit.
FailedOperation.ServerError The algorithm service is exceptional. Please retry.
InternalError Internal error.
InvalidParameter.InvalidParameter Invalid parameter.
InvalidParameterValue.AccountFaceNumExceed The number of faces in the account exceeds the limit.
InvalidParameterValue.DeleteFaceNumExceed The number of faces to be deleted exceeds the limit. Every person must have at least one face image.
InvalidParameterValue.FaceMatchThresholdIllegal Invalid FaceMatchThreshold parameter.
InvalidParameterValue.GroupExDescriptionsExceed The array length of the group's custom description fields exceeds the limit. Up to 5 fields can be created.
InvalidParameterValue.GroupExDescriptionsNameIdentical The name of the group's custom description field must be unique.
InvalidParameterValue.GroupExDescriptionsNameIllegal The name of the group's custom description field contains invalid characters. It can contain only letters, -, _, and digits.
InvalidParameterValue.GroupExDescriptionsNameTooLong The name of the group's custom description field exceeds the length limit.
InvalidParameterValue.GroupFaceNumExceed The number of faces in the group exceeds the limit.
InvalidParameterValue.GroupIdAlreadyExist The group ID already exists. It must be unique.
InvalidParameterValue.GroupIdIllegal The group ID contains invalid characters. It can contain only letters, digits, and special symbols (-%@#&_).
InvalidParameterValue.GroupIdNotExist The group ID does not exist.
InvalidParameterValue.GroupIdTooLong The group ID exceeds the length limit.
InvalidParameterValue.GroupIdsExceed The list of groups passed in exceeds the limit.
InvalidParameterValue.GroupNameAlreadyExist The group name already exists. It must be unique.
InvalidParameterValue.GroupNameIllegal The group name contains invalid characters. It can contain only letters, -, _, and digits.
InvalidParameterValue.GroupNameTooLong The group name exceeds the length limit.
InvalidParameterValue.GroupNumExceed The number of groups exceeds the limit. If you need more, please contact us.
InvalidParameterValue.GroupNumPerPersonExceed The number of groups exceeds the limit. One person can be added to up to 100 groups.
InvalidParameterValue.GroupTagIllegal The group remarks field contains invalid characters. It can contain only letters, -, _, and digits.
InvalidParameterValue.GroupTagTooLong The group remarks field exceeds the length limit.
InvalidParameterValue.ImageEmpty Empty image.
InvalidParameterValue.LimitExceed The number of returned results exceeds the limit.
InvalidParameterValue.NoFaceInGroups There are no faces in the specified group.
InvalidParameterValue.NoFaceInPhoto There are no faces in the image.
InvalidParameterValue.OffsetExceed The starting number is too large. Please check the length of the array to be requested.
InvalidParameterValue.PersonExDescriptionInfosExceed The array length of the person's custom description fields exceeds the limit. Up to 5 fields are allowed.
InvalidParameterValue.PersonExDescriptionsNameIdentical The name of the person's custom description field must be unique.
InvalidParameterValue.PersonExDescriptionsNameIllegal The name of the person's custom description field contains invalid characters. It can contain only letters, -, _, and digits.
InvalidParameterValue.PersonExDescriptionsNameTooLong The name of the person's custom description field exceeds the length limit.
InvalidParameterValue.PersonExistInGroup The ID of the corresponding person is already in the group.
InvalidParameterValue.PersonFaceNumExceed The number of face images for the person exceeds the limit. One person can have up to 5 face images.
InvalidParameterValue.PersonGenderIllegal An error occurred while setting person gender. 0: empty; 1: male; 2: female.
InvalidParameterValue.PersonIdAlreadyExist The person ID already exists. It must be unique.
InvalidParameterValue.PersonIdIllegal The person ID contains invalid characters. It can contain only letters, digits, and -%@#&_.
InvalidParameterValue.PersonIdNotExist The person ID does not exist.
InvalidParameterValue.PersonIdTooLong The person ID field exceeds the length limit.
InvalidParameterValue.PersonNameIllegal The person name contains invalid characters. It can contain only letters, -, _, and digits.
InvalidP