Passport OCR

Function

Passport OCR recognizes the text on the first page of a passport and returns the structured information in JSON format.

In the current version, all fields of a Chinese passport can be recognized. For non-Chinese passports, two lines of internationally standardized machine-readable codes on the bottom of each passport can be recognized, and 6 to 7 key fields can be extracted from the codes.For details about the constraints on using this API, see Constraints. For details about how to use this API, see Introduction to OCR.

Figure 1 Passport OCR example

If the image contains multiple cards and tickets, call Auto Classification OCR.

Prerequisites

Before using Passport OCR, you need to apply for the service and complete authentication. For details, see Subscribing to OCR and Authentication.

URI

POST https://{endpoint}/v2/{project_id}/ocr/passport

Table 1 Path parameters

Parameter

Mandatory

Description

endpoint

Yes

Domain name or IP address of the server bearing the REST service endpoint. The endpoint varies depending on services in different regions. For more details, see Endpoints.

For example, the endpoint of OCR in the CN North-Beijing4 region is ocr.cn-north-4.myhuaweicloud.com.

project_id

Yes

Project ID, which can be obtained from Obtaining a Project ID.

Request Parameters

Table 2 Request header parameters

Parameter

Mandatory

Type

Description

X-Auth-Token

Yes

String

User token

During API authentication using a token, the token is added to requests to obtain permissions for calling the API. The value of X-Subject-Token in the response header is the obtained token.

Content-Type

Yes

String

MIME type of the request body. The value is application/json.

Table 3 Request body parameters

Parameter

Mandatory

Type

Description

image

No. Set either this parameter or url.

String

Base64 character string converted from the image. The size cannot exceed 10 MB.

The narrow edge contains at least 15 pixels and the wide edge contains at most 4,096 pixels. The JPEG, JPG, PNG, BMP, and TIFF formats are supported.

url

No. Set either this parameter or image.

String

Image URL. Currently, the following URLs are supported:

  • Public network: HTTP/HTTPS URL
  • URL provided by OBS. You need to be authorized to use OBS data, including service authorization, temporary authorization, and anonymous public authorization. For details, see Configuring Access Permissions of OBS
NOTE:
  • The API response time depends on the image download time. If the image download takes a long time, the API call will fail.
  • Ensure that the storage service where the images to be detected reside is stable and reliable. OBS is recommended for storing image data.

country_code

No

String

Country code on the passport. The recognition mode is determined based on the country code.

  • If this parameter is left blank, OCR automatically matches the recognition mode based on the passport type identified by the service.
  • If you set this parameter to GENERAL, the passport is recognized based on the machine-readable code.
  • If this parameter is set to CHN, all fields in the Chinese passport are recognized.

Response Parameters

Response parameters and status codes vary in different recognition results. They are described as below.

Status code: 200

Table 4 Response body parameter

Parameter

Type

Description

result

PassportResult object

Calling result of a successful API call

result consists of the following three parts: 13 key fields, expressed in English; extra_info, passport information in the local official language; confidence, confidence scores of key fields. A higher confidence score indicates a more accurate result.

This parameter is not included when the API fails to be called.

Table 5 PassportResult

Parameter

Type

Description

passport_type

String

Passport type. Possible values are as follows:

  • P: ordinary passport
  • W: diplomatic passport
  • G: service passport

country_code

String

Country code

passport_number

String

Passport ID

nationality

String

Nationality of the passport holder

surname

String

Last name

given_name

String

Given game

sex

String

Gender

date_of_birth

String

Date of birth

date_of_expiry

String

Passport date of expiry

date_of_issue

String

Date of issue

place_of_birth

String

Place of birth

place_of_issue

String

Place of issue

issuing_authority

String

Issuing authority

The abbreviation of the issuing authority of each consulate is not unified. The abbreviation of Chinese issuing authority is P.R.China. For example, if the issuing authority is P.R.C, the recognition result is P.R.China.

confidence

Object

Confidence information of a related field. The value ranges from 0 to 1.

Confidence of related fields. A higher confidence indicates a more accurate result.

The confidence is not equal to the accuracy, and is calculated through related algorithms.

extra_info

Object

By default, this parameter is left blank. For a Chinese passport, extra_info contains Chinese character-described fields on the passport, such as the name and place of birth.

Status code: 400

Table 6 Response body parameters

Parameter

Type

Description

error_code

String

Error code of a failed API call. For details, see Error Codes.

If error code ModelArts.4204 is displayed, refer to Why Is a Message Stating "ModelArts.4204" Displayed When the OCR API Is Called?

This parameter is not included when the API is successfully called.

error_msg

String

Error message returned when the API fails to be called

This parameter is not included when the API is successfully called.

Request Example

  • The endpoint is the request URL for calling an API. Endpoints vary depending on services and regions. For details, see Endpoints.

    For example, Passport OCR is deployed in the CN North-Beijing4 region. The endpoint is ocr.cn-north-4.myhuaweicloud.com. The request URL is https://ocr.cn-north-4.myhuaweicloud.com/v2/{project_id}/ocr/passport. project_id is the project ID. For details about how to obtain the project ID, see Obtaining a Project ID.

  • For details about how to obtain a token, see Making an API Request.
  • Request example (Method 1: Use the image Base64 string.)
    POST https://{endpoint}/v2/{project_id}/ocr/passport
    Request Header:
    Content-Type: application/json
    X-Auth-Token: MIINRwYJKoZIhvcNAQcCoIINODCCDTQCAQExDTALBglghkgBZQMEAgEwgguVBgkqhkiG...
    Request Body:
    {
        "image":"/9j/4AAQSkZJRgABAgEASABIAAD/4RFZRXhpZgAATU0AKgAAAA...",
        "country_code": "GENERAL"
    }
  • Request example (Method 2: Use the image URL.)
    POST https://{endpoint}/v2/{project_id}/ocr/passport
    Request Header:
    Content-Type: application/json
    X-Auth-Token: MIINRwYJKoZIhvcNAQcCoIINODCCDTQCAQExDTALBglghkgBZQMEAgEwgguVBgkqhkiG...
    Request Body:
    {
        "url":"https://BucketName.obs.xxxx.com/ObjectName",
        "country_code": "GENERAL"
    }
  • Sample code for a Python 3 request (For codes in other languages, refer to the following sample or use OCR SDK.)
    # encoding:utf-8
    
    import requests
    import base64
    
    url = "https://{endpoint}/v2/{project_id}/ocr/passport"
    token = "Actual token value obtained by the user"
    headers = {'Content-Type': 'application/json', 'X-Auth-Token': token}
    
    imagepath = r'./data/passport-demo.png'
    with open(imagepath, "rb") as bin_data:
        image_data = bin_data.read()
    image_base64 = base64.b64encode(image_data).decode("utf-8")  # Base64 encoding of images.
    payload = {"image": image_base64}  # url or image.
    response = requests.post(url, headers=headers, json=payload)
    print(response.text)

Example Response

Status code: 200

Chinese passport

{
    "result": {
        "passport_type": "P", 
        "country_code": "CHN", 
        "passport_number": "ED999XXXX", 
        "nationality": "CHINESE", 
        "surname": "ZHANG", 
        "given_name": "SAN", 
        "sex": "F", 
        "date_of_birth": "1990-12-12", 
        "date_of_expiry": "2020-07-08", 
        "date_of_issue": "2010-07-09", 
        "place_of_birth": "HUNAN", 
        "place_of_issue": "GUANGDONG", 
        "issuing_authority": "MPS Exit & Entry Administration", 
        "extra_info": {
            "local_language": {
                 "name": "Name recognized from the image",
                "sex": "Gender recognized from the image",
                "place_of_birth": "Place of birth recognized from the image",
                "place_of_issue": "Place of issue recognized from the image",
                "issuing_authority": "Issuing authority recognized from the image",
                "nationality": "Nationality recognized from the image",
            }
        }, 
        "confidence": {
            "passport_type": 1.0, 
            "country_code": 1.0, 
            "passport_number": 0.9997, 
            "nationality": 1.0, 
            "surname": 0.9729, 
            "given_name": 0.9729, 
            "sex": 1.0, 
            "date_of_birth": 0.9998, 
            "date_of_expiry": 0.9995, 
            "date_of_issue": 0.9969, 
            "place_of_birth": 1.0, 
            "place_of_issue": 1.0, 
            "issuing_authority": 0.9985
        }
    }
}

Non-chinese passport

{
    "result": {
        "country_code": "ETF", 
        "surname": "HUZHAO", 
        "given_name": "ZHAOMIN DESALEGN ", 
        "passport_number": "EP435XXXX", 
        "date_of_birth": "1985-09-18", 
        "sex": "M", 
        "date_of_expiry": "2022-01-15", 
        "machine_code": "P<ETFHUZHAO<< ZHAOMIN <DESALEGN<<<<<<<<<<<<<<<", 
        "machine_code2": "EP435XXXX7ETF8509185M2201155<<<<<<<<<<<<<<08", 
        "extra_info": {},
        "confidence": {
            "country_code": 0.9727, 
            "surname": 0.9727, 
            "given_name": 0.9727, 
            "passport_number": 0.9558, 
            "date_of_birth": 0.9558, 
            "sex": 0.9558, 
            "date_of_expiry": 0.9558
        }
    }
}

Status code: 400

Failure response example

{
    "error_code": "AIS.0103", 
    "error_msg": "The image size does not meet the requirements." 
}

Status Codes

Status Code

Description

200

Success response

400

Failure response

For details about status codes, see Status Codes.

Error Codes

For details about error codes, see Error Codes.