Object Storage Service:Blind watermarking

SDK for Java

SDK for Java 3.17.4 or later is required.

import com.aliyun.oss.*;
import com.aliyun.oss.common.auth.EnvironmentVariableCredentialsProvider;
import com.aliyun.oss.common.comm.SignVersion;
import com.aliyun.oss.model.GenericResult;
import com.aliyun.oss.model.ProcessObjectRequest;

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.util.Formatter;

public class Demo {
    public static void main(String[] args) throws IOException {
        // Set the endpoint to match the region of your bucket.
        String endpoint = "https://oss-cn-hangzhou.aliyuncs.com";
        // Set the region ID corresponding to the endpoint. Example: cn-hangzhou.
        String region = "cn-hangzhou";
        // Load access credentials from environment variables.
        // Configure OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET before running this code.
        EnvironmentVariableCredentialsProvider credentialsProvider = new EnvironmentVariableCredentialsProvider();

        // Specify the bucket that contains the source image.
        String bucketName = "examplebucket";
        // Specify the source image path. Example: sourceDir/source.jpg.
        String sourceImage = "sourceDir/source.jpg";

        // Create an OSSClient instance using the V4 signature algorithm.
        ClientBuilderConfiguration clientBuilderConfiguration = new ClientBuilderConfiguration();
        clientBuilderConfiguration.setSignatureVersion(SignVersion.V4);
        OSS ossClient = OSSClientBuilder.create()
                .endpoint(endpoint)
                .credentialsProvider(credentialsProvider)
                .clientConfiguration(clientBuilderConfiguration)
                .region(region)
                .build();

        try {
            StringBuilder sbStyle = new StringBuilder();
            Formatter styleFormatter = new Formatter(sbStyle);

            // Encode the watermark text using URL-safe Base64 without padding.
            String content = "Copyright © Alibaba Cloud";
            String encodedContent = java.util.Base64.getUrlEncoder().withoutPadding()
                    .encodeToString(content.getBytes(StandardCharsets.UTF_8));
            String styleType = "image/blindwatermark,content_" + encodedContent;

            // Specify the output path for the watermarked image.
            String targetImage = "targetDir/target.jpg";
            styleFormatter.format("%s|sys/saveas,o_%s,b_%s",
                    styleType,
                    java.util.Base64.getUrlEncoder().withoutPadding()
                            .encodeToString(targetImage.getBytes(StandardCharsets.UTF_8)),
                    java.util.Base64.getUrlEncoder().withoutPadding()
                            .encodeToString(bucketName.getBytes(StandardCharsets.UTF_8)));

            ProcessObjectRequest request = new ProcessObjectRequest(bucketName, sourceImage, sbStyle.toString());
            GenericResult processResult = ossClient.processObject(request);

            BufferedReader reader = new BufferedReader(
                    new InputStreamReader(processResult.getResponse().getContent(), StandardCharsets.UTF_8));
            StringBuilder responseContent = new StringBuilder();
            String line;
            while ((line = reader.readLine()) != null) {
                responseContent.append(line).append("\n");
            }
            reader.close();
            processResult.getResponse().getContent().close();
            System.out.println(responseContent.toString());
        } catch (OSSException oe) {
            System.err.println("Error Message: " + oe.getErrorMessage());
            System.err.println("Error Code: " + oe.getErrorCode());
            System.err.println("Request ID: " + oe.getRequestId());
        } catch (ClientException ce) {
            System.err.println("Error Message: " + ce.getMessage());
        } finally {
            if (ossClient != null) {
                ossClient.shutdown();
            }
        }
    }
}

SDK for Python

SDK for Python 2.18.4 or later is required.

# -*- coding: utf-8 -*-
import base64
import oss2
from oss2.credentials import EnvironmentVariableCredentialsProvider

# Load access credentials from environment variables.
# Configure OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET before running this code.
auth = oss2.ProviderAuth(EnvironmentVariableCredentialsProvider())

# Set the endpoint to match the region of your bucket.
endpoint = 'https://oss-cn-hangzhou.aliyuncs.com'

# Specify the bucket that contains the source image.
source_bucket_name = 'examplebucket'
# Specify the bucket to store the watermarked image. Must be in the same region as the source bucket.
target_bucket_name = 'examplebucket-target'
# Specify the source image path. Example: sourceDir/source.jpg.
source_image_name = 'sourceDir/source.jpg'

bucket = oss2.Bucket(auth, endpoint, source_bucket_name)

# Encode the watermark text using URL-safe Base64.
content = 'Copyright © Alibaba Cloud'
style = "image/blindwatermark,content_{0}".format(
    oss2.compat.to_string(base64.urlsafe_b64encode(oss2.compat.to_bytes(content))))

# Specify the output path for the watermarked image.
target_image_name = 'targetDir/target.jpg'
process = "{0}|sys/saveas,o_{1},b_{2}".format(
    style,
    oss2.compat.to_string(base64.urlsafe_b64encode(oss2.compat.to_bytes(target_image_name))),
    oss2.compat.to_string(base64.urlsafe_b64encode(oss2.compat.to_bytes(target_bucket_name))))

result = bucket.process_object(source_image_name, process)
print(result)

SDK for Go

SDK for Go 3.0.2 or later is required.

package main

import (
    "encoding/base64"
    "fmt"
    "os"
    "strings"
    "github.com/aliyun/aliyun-oss-go-sdk/oss"
)

func main() {
    // Load access credentials from environment variables.
    // Configure OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET before running this code.
    provider, err := oss.NewEnvironmentVariableCredentialsProvider()
    if err != nil {
        fmt.Println("Error:", err)
        os.Exit(-1)
    }

    // Set the endpoint to match the region of your bucket.
    client, err := oss.New("https://oss-cn-hangzhou.aliyuncs.com", "", "",
        oss.SetCredentialsProvider(&provider))
    if err != nil {
        fmt.Println("Error:", err)
        os.Exit(-1)
    }

    // Specify the bucket that contains the source image.
    bucketName := "examplebucket"
    bucket, err := client.Bucket(bucketName)
    if err != nil {
        handleError(err)
        return
    }

    // Specify the source image path. Example: sourceDir/source.jpg.
    sourceImageName := "sourceDir/source.jpg"
    // Specify the bucket to store the watermarked image. Must be in the same region.
    targetBucketName := "examplebucket-target"
    // Specify the output path for the watermarked image.
    targetImageName := "targetDir/target.jpg"

    // Encode the watermark text using URL-safe Base64 without padding.
    content := "Copyright © Alibaba Cloud"
    encodedContent := strings.TrimRight(base64.URLEncoding.EncodeToString([]byte(content)), "=")
    style := fmt.Sprintf("image/blindwatermark,content_%s", encodedContent)

    encodedImageName := strings.TrimRight(base64.URLEncoding.EncodeToString([]byte(targetImageName)), "=")
    encodedBucketName := strings.TrimRight(base64.URLEncoding.EncodeToString([]byte(targetBucketName)), "=")
    process := fmt.Sprintf("%s|sys/saveas,o_%s,b_%s", style, encodedImageName, encodedBucketName)

    result, err := bucket.ProcessObject(sourceImageName, process)
    if err != nil {
        handleError(err)
    } else {
        fmt.Println(result)
    }
}

func handleError(err error) {
    fmt.Println("Error:", err)
    os.Exit(-1)
}

SDK for PHP

SDK for PHP 2.7.0 or later is required.

<?php
if (is_file(__DIR__ . '/../autoload.php')) {
    require_once __DIR__ . '/../autoload.php';
}
if (is_file(__DIR__ . '/../vendor/autoload.php')) {
    require_once __DIR__ . '/../vendor/autoload.php';
}

use OSS\OssClient;
use OSS\Core\OssException;

// Load access credentials from environment variables.
// Configure OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET before running this code.
$accessKeyId = getenv("OSS_ACCESS_KEY_ID");
$accessKeySecret = getenv("OSS_ACCESS_KEY_SECRET");

// Set the endpoint to match the region of your bucket.
$endpoint = "https://oss-cn-hangzhou.aliyuncs.com";

// Specify the bucket that contains the source image.
$bucket = "examplebucket";
// Specify the source image path. Example: sourceDir/source.jpg.
$object = "sourceDir/source.jpg";
// Specify the output path for the watermarked image.
$save_object = "targetDir/target.jpg";

function base64url_encode($data)
{
    return rtrim(strtr(base64_encode($data), '+/', '-_'), '=');
}

try {
    $ossClient = new OssClient($accessKeyId, $accessKeySecret, $endpoint, false);

    // Encode the watermark text using URL-safe Base64 without padding.
    $content = "Copyright © Alibaba Cloud";
    $encodedContent = base64url_encode($content);
    $style = "image/blindwatermark,content_$encodedContent";

    $process = $style .
               '|sys/saveas,' .
               'o_' . base64url_encode($save_object) .
               ',b_' . base64url_encode($bucket);

    $result = $ossClient->processObject($bucket, $object, $process);
    print_r($result);
} catch (OssException $e) {
    echo "Error: " . $e->getMessage();
}
?>

For other languages, see Save As.

REST API

Use x-oss-process in a PostObject request. Include parameters in the request body. To calculate the Authorization header, see Signature V4 (recommended).

The following example embeds the text "Alibaba Cloud Copyright" with low strength and quality 90, then saves the result to oss://image-demo/outobjprefix.jpg:

POST /example.jpg?x-oss-process HTTP/1.1
Host: image-demo.oss-cn-hangzhou.aliyuncs.com
Date: Fri, 28 Oct 2022 06:40:10 GMT
Authorization: SignatureValue

x-oss-process=image/blindwatermark,content_6Zi_6YeM5LqR54mI5p2D5omA5pyJ,s_low,q_90|sys/saveas,b_aW1hZ2UtZGVtbw,o_b3V0b2JqcHJlZml4LmpwZw

SDK for Java

SDK for Java 3.17.4 or later is required.

import com.aliyun.oss.*;
import com.aliyun.oss.common.auth.EnvironmentVariableCredentialsProvider;
import com.aliyun.oss.common.comm.SignVersion;
import com.aliyun.oss.model.AsyncProcessObjectRequest;
import com.aliyun.oss.model.AsyncProcessObjectResult;

import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.util.Base64;

public class Demo {
    public static void main(String[] args) throws IOException {
        // Set the endpoint to match the region of your bucket.
        String endpoint = "https://oss-cn-hangzhou.aliyuncs.com";
        // Set the region ID corresponding to the endpoint. Example: cn-hangzhou.
        String region = "cn-hangzhou";
        // Load access credentials from environment variables.
        EnvironmentVariableCredentialsProvider credentialsProvider = new EnvironmentVariableCredentialsProvider();

        // Specify the bucket that contains the watermarked image.
        String bucketName = "examplebucket";
        // Specify the watermarked image path.
        String sourceKey = "targetDir/target.jpg";
        // Specify the MNS topic to receive the extraction result.
        String topic = "imm-blindwatermark-test";

        // Create an OSSClient instance using the V4 signature algorithm.
        ClientBuilderConfiguration clientBuilderConfiguration = new ClientBuilderConfiguration();
        clientBuilderConfiguration.setSignatureVersion(SignVersion.V4);
        OSS ossClient = OSSClientBuilder.create()
                .endpoint(endpoint)
                .credentialsProvider(credentialsProvider)
                .clientConfiguration(clientBuilderConfiguration)
                .region(region)
                .build();

        try {
            // Extract the watermark text from the image.
            String style = "image/deblindwatermark,s_low,t_text";
            String encodedTopic = Base64.getUrlEncoder().withoutPadding()
                    .encodeToString(topic.getBytes(StandardCharsets.UTF_8));
            String process = String.format("%s|sys/notify,topic_%s", style, encodedTopic);

            AsyncProcessObjectRequest request = new AsyncProcessObjectRequest(bucketName, sourceKey, process);
            AsyncProcessObjectResult result = ossClient.asyncProcessObject(request);

            System.out.println(result.getRequestId()); // OSS request ID for tracking
            System.out.println(result.getTaskId());    // Task ID for the asynchronous job
        } catch (OSSException oe) {
            System.err.println("Error Message: " + oe.getErrorMessage());
            System.err.println("Error Code: " + oe.getErrorCode());
            System.err.println("Request ID: " + oe.getRequestId());
        } catch (ClientException ce) {
            System.err.println("Error Message: " + ce.getMessage());
        } finally {
            if (ossClient != null) {
                ossClient.shutdown();
            }
        }
    }
}

SDK for Python

SDK for Python 2.18.4 or later is required.

# -*- coding: utf-8 -*-
import base64
import oss2
from oss2.credentials import EnvironmentVariableCredentialsProvider

# Set the endpoint to match the region of your bucket.
endpoint = 'https://oss-cn-hangzhou.aliyuncs.com'
# Load access credentials from environment variables.
# Configure OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET before running this code.
auth = oss2.ProviderAuth(EnvironmentVariableCredentialsProvider())

# Specify the bucket that contains the watermarked image.
bucket_name = 'examplebucket'
# Specify the watermarked image path.
source_key = 'targetDir/target.jpg'
# Specify the MNS topic to receive the extraction result.
topic = 'imm-blindwatermark-test'

bucket = oss2.Bucket(auth, endpoint, bucket_name)

# Extract the watermark text from the image.
style = 'image/deblindwatermark,s_low,t_text'
process = "{0}|sys/notify,topic_{1}".format(
    style,
    oss2.compat.to_string(base64.urlsafe_b64encode(oss2.compat.to_bytes(topic))).replace('=', ''))

result = bucket.async_process_object(source_key, process)
print(result.request_id)  # OSS request ID for tracking
print(result.task_id)     # Task ID for the asynchronous job

SDK for Go

SDK for Go 3.0.2 or later is required.

package main

import (
    "encoding/base64"
    "fmt"
    "os"
    "strings"
    "github.com/aliyun/aliyun-oss-go-sdk/oss"
)

func main() {
    // Load access credentials from environment variables.
    // Configure OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET before running this code.
    provider, err := oss.NewEnvironmentVariableCredentialsProvider()
    if err != nil {
        fmt.Println("Error:", err)
        os.Exit(-1)
    }

    // Set the endpoint to match the region of your bucket.
    endpoint := "https://oss-cn-hangzhou.aliyuncs.com"
    client, err := oss.New(endpoint, "", "", oss.SetCredentialsProvider(provider))
    if err != nil {
        fmt.Println("Error:", err)
        os.Exit(-1)
    }

    // Specify the bucket that contains the watermarked image.
    bucketName := "examplebucket"
    bucket, err := client.Bucket(bucketName)
    if err != nil {
        handleError(err)
        return
    }

    // Specify the watermarked image path.
    sourceKey := "targetDir/target.jpg"
    // Specify the MNS topic to receive the extraction result.
    topic := "imm-blindwatermark-test"

    // Extract the watermark text from the image.
    style := "image/deblindwatermark,s_low,t_text"
    encodedTopic := strings.TrimRight(base64.URLEncoding.EncodeToString([]byte(topic)), "=")
    process := fmt.Sprintf("%s|sys/notify,topic_%s", style, encodedTopic)

    result, err := bucket.AsyncProcessObject(sourceKey, process)
    if err != nil {
        handleError(err)
    } else {
        fmt.Println(result.RequestID) // OSS request ID for tracking
        fmt.Println(result.TaskId)   // Task ID for the asynchronous job
    }
}

func handleError(err error) {
    fmt.Fprintf(os.Stderr, "Error: %v\n", err)
    os.Exit(-1)
}

SDK for PHP

SDK for PHP 2.7.0 or later is required.

<?php
if (is_file(__DIR__ . '/../autoload.php')) {
    require_once __DIR__ . '/../autoload.php';
}
if (is_file(__DIR__ . '/../vendor/autoload.php')) {
    require_once __DIR__ . '/../vendor/autoload.php';
}

// Load access credentials from environment variables.
// Configure OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET before running this code.
$accessKeyId = getenv("OSS_ACCESS_KEY_ID");
$accessKeySecret = getenv("OSS_ACCESS_KEY_SECRET");

// Set the endpoint to match the region of your bucket.
$endpoint = 'https://oss-cn-hangzhou.aliyuncs.com';

// Specify the bucket that contains the watermarked image.
$bucketName = 'examplebucket';
// Specify the watermarked image path.
$sourceKey = 'targetDir/target.jpg';

function base64_url_encode($input) {
    return strtr(base64_encode($input), '+/', '-_');
}

try {
    $client = new OssClient($accessKeyId, $accessKeySecret, $endpoint);

    // Specify the MNS topic to receive the extraction result.
    $topic = 'imm-blindwatermark-test';

    // Extract the watermark text from the image.
    $style = 'image/deblindwatermark,s_low,t_text';
    $encodedTopic = str_replace('=', '', base64_url_encode($topic));
    $process = sprintf('%s|sys/notify,topic_%s', $style, $encodedTopic);

    $result = $client->asyncProcessObject($bucketName, $sourceKey, $process);

    $decodedResult = json_decode($result, true);
    echo "Request ID: " . $decodedResult['RequestId'] . "\n"; // OSS request ID for tracking
    echo "Task ID: " . $decodedResult['TaskId'] . "\n";      // Task ID for the asynchronous job
} catch (OssException $e) {
    echo "Error: " . $e->getMessage() . "\n";
}
?>

For other languages, see Asynchronous processing.

REST API

Use x-oss-async-process in a PostObject request. Include parameters in the request body.

The following example parses the watermark from outobjprefix.jpg and delivers the result to the MNS topic doc-images:

POST /outobjprefix.jpg?x-oss-async-process HTTP/1.1
Host: image-demo.oss-cn-hangzhou.aliyuncs.com
Date: Fri, 28 Oct 2022 06:40:10 GMT
Authorization: SignatureValue

x-oss-async-process=image/deblindwatermark|sys/notify,topic_ZG9jLWltYWdlcw

Add a blind watermark

Action: image/blindwatermark

The sys/saveas parameter is required to save the watermarked image. For details, see Save an image to a specified location.

Parse a blind watermark

Action: image/deblindwatermark

The sys/notify parameter is required to receive the extraction result. For details, see Notifications.