SignUserImage - AI DeepSign - Alibaba Cloud Documentation Center

Operation description

Specify at least one of ImageUrl and ObjectKey. If both are specified, ObjectKey takes precedence.
When you use ObjectKey, the system verifies that the ObjectKey belongs to the current caller. Cross-tenant access is not allowed.
Supported image formats are JPEG and PNG. Unsupported formats return the C2PA_FORMAT_UNSUPPORTED error.
If the original image already contains a C2PA signature, the system retains the original signature as an ingredient and appends a new signature.
Use the ClientToken parameter to ensure idempotence. Make sure the value is unique across different requests and does not exceed 64 characters.

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RAM authorization

No authorization for this operation. If you encounter issues with this operation, contact technical support.

Request parameters

Parameter	Type	Required	Description	Example
ClientToken	string	No	The client token that is used to ensure the idempotence of the request. The client generates this value. Make sure the value is unique across different requests. ClientToken supports only ASCII characters and cannot exceed 64 characters in length.
ImageUrl	string	No	The URL of the image to be signed. HTTP and HTTPS URLs are supported. Specify at least one of `ImageUrl` and `ObjectKey`.
ObjectKey	string	No	The ObjectKey of the image to be signed in OSS. When you use `ObjectKey`, make sure the key belongs to the namespace of the current caller. Specify at least one of `ImageUrl` and `ObjectKey`.

Response elements

Element	Type	Description	Example
	object
SignTime	string	The signing time in ISO 8601 format, such as `2026-01-15T08:30:00Z`.
RequestId	string	The request ID.
SignedImageUrl	string	The pre-signed download URL of the signed image.
CertificateSubject	string	The subject information of the signing certificate.
ObjectKey	string	The ObjectKey of the signed image in OSS. You can use this value for subsequent API calls.
Algorithm	string	The algorithm used for signing, such as ps256 or es256.
Success	boolean	Indicates whether the request was successful.
Message	string	The additional information. The value "success" is returned if the request succeeds.
HttpStatusCode	integer	The HTTP status code. The value 200 is returned if the request succeeds.
Code	string	The business error code. The value "OK" is returned if the request succeeds.

Examples

Success response

JSON format

{
  "SignTime": "",
  "RequestId": "",
  "SignedImageUrl": "",
  "CertificateSubject": "",
  "ObjectKey": "",
  "Algorithm": "",
  "Success": true,
  "Message": "",
  "HttpStatusCode": 0,
  "Code": ""
}

Error codes

HTTP status code	Error code	Error message	Description
400	IdempotentParameterMismatch	The request uses the same client token as a previous, but non-identical request. Do not reuse a client token with different requests, unless the requests are identical.

See Error Codes for a complete list.

Release notes

See Release Notes for a complete list.