How to process images using OSS SDK for Java - Object Storage Service

Image Processing (IMG) est un service de traitement d'images sécurisé, rentable et hautement fiable, fourni par Object Storage Service (OSS). Après avoir téléchargé vos images sources vers OSS, vous pouvez appeler des opérations API RESTful pour les traiter à tout moment, depuis n'importe quel appareil connecté.

Notes d'utilisation

Cette rubrique utilise le point de terminaison public de la région Chine (Hangzhou). Pour accéder à OSS depuis d'autres services Alibaba Cloud dans la même région, utilisez un point de terminaison interne. Pour plus de détails sur les régions et points de terminaison pris en charge, consultez Régions et points de terminaison.
Les identifiants d'accès utilisés dans cette rubrique sont obtenus à partir des variables d'environnement. Pour plus d'informations, consultez Configuration des identifiants d'accès.
Cette rubrique explique comment créer une instance OSSClient avec un point de terminaison OSS. Pour d'autres configurations, telles que l'utilisation d'un domaine personnalisé ou l'authentification avec des identifiants du Security Token Service (STS), consultez Configuration du client.

Utiliser des paramètres IMG pour traiter des images

Utiliser un seul paramètre IMG pour traiter une image

import com.aliyun.oss.*;
import com.aliyun.oss.common.auth.*;
import com.aliyun.oss.common.comm.SignVersion;
import com.aliyun.oss.model.GetObjectRequest;
import java.io.File;

public class Demo {
    public static void main(String[] args) throws Throwable {
        // In this example, the endpoint of the China (Hangzhou) region is used. Specify your actual endpoint. 
        String endpoint = "https://oss-cn-hangzhou.aliyuncs.com";
        // Obtain access credentials from environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured. 
        EnvironmentVariableCredentialsProvider credentialsProvider = CredentialsProviderFactory.newEnvironmentVariableCredentialsProvider();
        // Specify the name of the bucket. Example: examplebucket. 
        String bucketName = "examplebucket";
        // Specify the full path of the object. Do not include the bucket name in the full path. 
        String objectName = "exampleobject.jpg";
        // Specify the full path to which you want to save the processed image. Example: D:\\localpath\\example-resize.jpg. If a file with the same name already exists in the path, the processed image overwrites the file. Otherwise, the processed image is saved in the path. 
        String localPath = "D:\\localpath\\example-resize.jpg";
        // Specify the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the region to cn-hangzhou.
        String region = "cn-hangzhou";

        // Create an OSSClient instance.
        // Call the shutdown method to release resources when the OSSClient is no longer in use. 
        ClientBuilderConfiguration clientBuilderConfiguration = new ClientBuilderConfiguration();
        clientBuilderConfiguration.setSignatureVersion(SignVersion.V4);        
        OSS ossClient = OSSClientBuilder.create()
        .endpoint(endpoint)
        .credentialsProvider(credentialsProvider)
        .clientConfiguration(clientBuilderConfiguration)
        .region(region)               
        .build();

        try {
            // Resize the image to a height and width of 100 pixels. 
            String style = "image/resize,m_fixed,w_100,h_100";
            GetObjectRequest request = new GetObjectRequest(bucketName, objectName);
            request.setProcess(style);
            // Name the processed image example-resize.jpg and save the image to your local computer. 
            // If you specify only the name of a local file such as example-resize.jpg without specifying the local path of the file, the processed image is saved to the local path of the project to which the sample program belongs. 
            ossClient.getObject(request, new File(localPath));
        } catch (OSSException oe) {
            System.out.println("Caught an OSSException, which means your request made it to OSS, "
                    + "but was rejected with an error response for some reason.");
            System.out.println("Error Message:" + oe.getErrorMessage());
            System.out.println("Error Code:" + oe.getErrorCode());
            System.out.println("Request ID:" + oe.getRequestId());
            System.out.println("Host ID:" + oe.getHostId());
        } catch (ClientException ce) {
            System.out.println("Caught an ClientException, which means the client encountered "
                    + "a serious internal problem while trying to communicate with OSS, "
                    + "such as not being able to access the network.");
            System.out.println("Error Message:" + ce.getMessage());
        } finally {
            if (ossClient != null) {
                ossClient.shutdown();
            }
        }
    }
}

Utiliser différents paramètres IMG pour traiter une image

import com.aliyun.oss.*;
import com.aliyun.oss.common.auth.*;
import com.aliyun.oss.common.comm.SignVersion;
import com.aliyun.oss.model.GetObjectRequest;
import java.io.File;

public class Demo {
    public static void main(String[] args) throws Throwable {
        // In this example, the endpoint of the China (Hangzhou) region is used. Specify your actual endpoint. 
        String endpoint = "https://oss-cn-hangzhou.aliyuncs.com";
        // Obtain access credentials from environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured. 
        EnvironmentVariableCredentialsProvider credentialsProvider = CredentialsProviderFactory.newEnvironmentVariableCredentialsProvider();
        // Specify the name of the bucket. Example: examplebucket. 
        String bucketName = "examplebucket";
        // Specify the full path of the object. Do not include the bucket name in the full path. 
        String objectName = "exampleobject.jpg";
        // Specify the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the region to cn-hangzhou.
        String region = "cn-hangzhou";

        // Create an OSSClient instance.
        // Call the shutdown method to release resources when the OSSClient is no longer in use. 
        ClientBuilderConfiguration clientBuilderConfiguration = new ClientBuilderConfiguration();
        clientBuilderConfiguration.setSignatureVersion(SignVersion.V4);        
        OSS ossClient = OSSClientBuilder.create()
        .endpoint(endpoint)
        .credentialsProvider(credentialsProvider)
        .clientConfiguration(clientBuilderConfiguration)
        .region(region)               
        .build();

        try {
            // Resize the image to a height and width of 100 pixels. 
            String style = "image/resize,m_fixed,w_100,h_100";
            GetObjectRequest request = new GetObjectRequest(bucketName, objectName);
            request.setProcess(style);
            // Name the processed image example-resize.jpg and save the image to your local computer. 
            // Specify the full path to which you want to save the processed image. Example: D:\\localpath\\example-resize.jpg. If a file with the same name already exists in the path, the processed image overwrites the file. Otherwise, the processed image is saved in the path. 
            // If you specify only the name of a local file such as example-resize.jpg without specifying the local path of the file, the processed image is saved to the local path of the project to which the sample program belongs. 
            ossClient.getObject(request, new File("D:\\localpath\\example-resize.jpg"));

            // Crop the image to a height and width of 100 pixels by setting the coordinate pair to (100, 100). 
            style = "image/crop,w_100,h_100,x_100,y_100";
            request = new GetObjectRequest(bucketName, objectName);
            request.setProcess(style);
            // Name the processed image example-crop.jpg and save the image to your local computer. 
            ossClient.getObject(request, new File("D:\\localpath\\example-crop.jpg"));

            // Rotate the image 90 degrees. 
            style = "image/rotate,90";
            request = new GetObjectRequest(bucketName, objectName);
            request.setProcess(style);
            // Name the processed image example-rotate.jpg and save the image to your local computer. 
            ossClient.getObject(request, new File("D:\\localpath\\example-rotate.jpg"));

            // Add a text watermark to the image. 
            // After the text watermark content is encoded in Base64, replace plus signs (+) in the encoded result with hyphens (-) and forward slashes (/) with underscores (_), and remove equal signs (=) at the end. Then, you can obtain the watermark string. 
            // Specify Hello World as the content of the text watermark, and encode the text content. Then, you can obtain the SGVsbG8gV29ybGQ string. 
            style = "image/watermark,text_SGVsbG8gV29ybGQ";
            request = new GetObjectRequest(bucketName, objectName);
            request.setProcess(style);
            // Name the processed image example-watermarktext.jpg and save the image to your local computer. 
            ossClient.getObject(request, new File("D:\\localpath\\example-watermarktext.jpg"));

            // Add an image watermark to the image. Make sure that the watermark image is stored in the bucket that stores the source image. 
            // After the full path of the watermark image is encoded in Base64, replace plus signs (+) in the encoded result with hyphens (-) and forward slashes (/) with underscores (_), and remove equal signs (=) at the end. Then, you can obtain the watermark string. 
            // Specify panda.jpg as the full path of the watermark image, and encode the full path. Then, you can obtain the cGFuZGEuanBn string. 
            style = "image/watermark,image_cGFuZGEuanBn";
            request = new GetObjectRequest(bucketName, objectName);
            request.setProcess(style);
            // Name the processed image example-watermarkimage.jpg and save the image to your local computer. 
            ossClient.getObject(request, new File("D:\\localpath\\example-watermarkimage.jpg"));
        } catch (OSSException oe) {
            System.out.println("Caught an OSSException, which means your request made it to OSS, "
                    + "but was rejected with an error response for some reason.");
            System.out.println("Error Message:" + oe.getErrorMessage());
            System.out.println("Error Code:" + oe.getErrorCode());
            System.out.println("Request ID:" + oe.getRequestId());
            System.out.println("Host ID:" + oe.getHostId());
        } catch (ClientException ce) {
            System.out.println("Caught an ClientException, which means the client encountered "
                    + "a serious internal problem while trying to communicate with OSS, "
                    + "such as not being able to access the network.");
            System.out.println("Error Message:" + ce.getMessage());
        } finally {
            if (ossClient != null) {
                ossClient.shutdown();
             }
        }
    }
}

Utiliser plusieurs paramètres IMG pour traiter une image simultanément

L'exemple de code suivant montre comment utiliser plusieurs paramètres IMG pour traiter une image simultanément. Séparez les paramètres IMG par des barres obliques (/).

import com.aliyun.oss.*;
import com.aliyun.oss.common.auth.*;
import com.aliyun.oss.common.comm.SignVersion;
import com.aliyun.oss.model.GetObjectRequest;
import java.io.File;

public class Demo {
    public static void main(String[] args) throws Throwable {
        // In this example, the endpoint of the China (Hangzhou) region is used. Specify your actual endpoint. 
        String endpoint = "https://oss-cn-hangzhou.aliyuncs.com";
        // Obtain access credentials from environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured. 
        EnvironmentVariableCredentialsProvider credentialsProvider = CredentialsProviderFactory.newEnvironmentVariableCredentialsProvider();
        // Specify the name of the bucket. Example: examplebucket. 
        String bucketName = "examplebucket";
        // Specify the full path of the object. Do not include the bucket name in the full path. 
        String objectName = "exampleobject.jpg";
        // Specify the full path to which you want to save the processed image. Example: D:\\localpath\\example-new.jpg. If a file with the same name already exists in the path, the processed image overwrites the file. Otherwise, the processed image is saved in the path. 
        String pathName = "D:\\localpath\\example-new.jpg";
        // Specify the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the region to cn-hangzhou.
        String region = "cn-hangzhou";

        // Create an OSSClient instance.
        // Call the shutdown method to release resources when the OSSClient is no longer in use. 
        ClientBuilderConfiguration clientBuilderConfiguration = new ClientBuilderConfiguration();
        clientBuilderConfiguration.setSignatureVersion(SignVersion.V4);        
        OSS ossClient = OSSClientBuilder.create()
        .endpoint(endpoint)
        .credentialsProvider(credentialsProvider)
        .clientConfiguration(clientBuilderConfiguration)
        .region(region)               
        .build();

        try {
            // Resize the image to a height and width of 100 pixels, and rotate the image 90 degrees. 
            String style = "image/resize,m_fixed,w_100,h_100/rotate,90";
            GetObjectRequest request = new GetObjectRequest(bucketName, objectName);
            request.setProcess(style);
            // Name the processed image example-new.jpg and save the image to your local computer. 
            // If you specify only the name of a local file such as example-new.jpg without specifying the local path of the file, the processed image is saved to the local path of the project to which the sample program belongs. 
            ossClient.getObject(request, new File("D:\\localpath\\example-new.jpg"));
        } catch (OSSException oe) {
            System.out.println("Caught an OSSException, which means your request made it to OSS, "
                    + "but was rejected with an error response for some reason.");
            System.out.println("Error Message:" + oe.getErrorMessage());
            System.out.println("Error Code:" + oe.getErrorCode());
            System.out.println("Request ID:" + oe.getRequestId());
            System.out.println("Host ID:" + oe.getHostId());
        } catch (ClientException ce) {
            System.out.println("Caught an ClientException, which means the client encountered "
                    + "a serious internal problem while trying to communicate with OSS, "
                    + "such as not being able to access the network.");
            System.out.println("Error Message:" + ce.getMessage());
        } finally {
            if (ossClient != null) {
                ossClient.shutdown();
            }
        }
    }
}

Utiliser un style d'image pour traiter une image

Vous pouvez créer un style d'image dans la console OSS et y encapsuler plusieurs paramètres IMG. Utilisez ensuite ce style pour traiter des images. Pour plus d'informations, consultez Styles d'image.

L'exemple de code suivant montre comment utiliser un style d'image pour traiter une image :

import com.aliyun.oss.*;
import com.aliyun.oss.common.auth.*;
import com.aliyun.oss.common.comm.SignVersion;
import com.aliyun.oss.model.GetObjectRequest;
import java.io.File;

public class Demo {
    public static void main(String[] args) throws Throwable {
        // In this example, the endpoint of the China (Hangzhou) region is used. Specify your actual endpoint. 
        String endpoint = "https://oss-cn-hangzhou.aliyuncs.com";
        // Obtain access credentials from environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured. 
        EnvironmentVariableCredentialsProvider credentialsProvider = CredentialsProviderFactory.newEnvironmentVariableCredentialsProvider();
        // Specify the name of the bucket. Example: examplebucket. 
        String bucketName = "examplebucket";
        // Specify the full path of the object. Do not include the bucket name in the full path. 
        String objectName = "exampleobject.jpg";
        // Specify the full path to which you want to save the processed image. Example: D:\\localpath\\example-new.jpg. If a file with the same name already exists in the path, the processed image overwrites the file. Otherwise, the processed image is saved in the path. 
        String pathName = "D:\\localpath\\example-new.jpg";
        // Specify the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the region to cn-hangzhou.
        String region = "cn-hangzhou";

        // Create an OSSClient instance.
        // Call the shutdown method to release resources when the OSSClient is no longer in use. 
        ClientBuilderConfiguration clientBuilderConfiguration = new ClientBuilderConfiguration();
        clientBuilderConfiguration.setSignatureVersion(SignVersion.V4);        
        OSS ossClient = OSSClientBuilder.create()
        .endpoint(endpoint)
        .credentialsProvider(credentialsProvider)
        .clientConfiguration(clientBuilderConfiguration)
        .region(region)               
        .build();

        try {
            // Use a custom image style to process the image. 
            // In this example, replace yourCustomStyleName with the name of the image style that you created in the OSS console. 
            String style = "style/yourCustomStyleName";
            GetObjectRequest request = new GetObjectRequest(bucketName, objectName);
            request.setProcess(style);
            // Name the processed image example-new.jpg and save the image to your local computer. 
            // If you specify only the name of a local file such as example-new.jpg without specifying the local path of the file, the processed image is saved to the local path of the project to which the sample program belongs. 
            ossClient.getObject(request, new File(pathName));
        } catch (OSSException oe) {
            System.out.println("Caught an OSSException, which means your request made it to OSS, "
                    + "but was rejected with an error response for some reason.");
            System.out.println("Error Message:" + oe.getErrorMessage());
            System.out.println("Error Code:" + oe.getErrorCode());
            System.out.println("Request ID:" + oe.getRequestId());
            System.out.println("Host ID:" + oe.getHostId());
        } catch (ClientException ce) {
            System.out.println("Caught an ClientException, which means the client encountered "
                    + "a serious internal problem while trying to communicate with OSS, "
                    + "such as not being able to access the network.");
            System.out.println("Error Message:" + ce.getMessage());
        } finally {
            if (ossClient != null) {
                ossClient.shutdown();
            }
        }
    }
}

Enregistrer les images traitées

Par défaut, IMG n'enregistre pas les images traitées. Appelez l'opération ImgSaveAs pour enregistrer les images dans le bucket contenant les images sources.

Le code suivant montre comment enregistrer une image traitée :

import com.aliyun.oss.*;
import com.aliyun.oss.common.auth.*;
import com.aliyun.oss.common.comm.SignVersion;
import com.aliyun.oss.common.utils.BinaryUtil;
import com.aliyun.oss.common.utils.IOUtils;
import com.aliyun.oss.model.GenericResult;
import com.aliyun.oss.model.ProcessObjectRequest;
import java.util.Formatter;

public class Demo {
    public static void main(String[] args) throws Throwable {
        // In this example, the endpoint of the China (Hangzhou) region is used. Specify your actual endpoint. 
        String endpoint = "https://oss-cn-hangzhou.aliyuncs.com";
        // Obtain access credentials from environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured. 
        EnvironmentVariableCredentialsProvider credentialsProvider = CredentialsProviderFactory.newEnvironmentVariableCredentialsProvider();
        // Specify the name of the bucket. Example: examplebucket. 
        String bucketName = "examplebucket";
        // Specify the full path of the object. Do not include the bucket name in the full path. 
        String sourceImage = "exampleimage.png";
        // Specify the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the region to cn-hangzhou.
        String region = "cn-hangzhou";

        // Create an OSSClient instance.
        // Call the shutdown method to release resources when the OSSClient is no longer in use. 
        ClientBuilderConfiguration clientBuilderConfiguration = new ClientBuilderConfiguration();
        clientBuilderConfiguration.setSignatureVersion(SignVersion.V4);        
        OSS ossClient = OSSClientBuilder.create()
        .endpoint(endpoint)
        .credentialsProvider(credentialsProvider)
        .clientConfiguration(clientBuilderConfiguration)
        .region(region)               
        .build();

        try {
            // Resize the image to a height and width of 100 pixels. 
            StringBuilder sbStyle = new StringBuilder();
            Formatter styleFormatter = new Formatter(sbStyle);
            String styleType = "image/resize,m_fixed,w_100,h_100";
            // Name the processed image example-resize.png and save the image to the bucket in which the source image is stored. 
            // Specify the full path of the object. Do not include the bucket name in the full path. 
            String targetImage = "example-resize.png";
            styleFormatter.format("%s|sys/saveas,o_%s,b_%s", styleType,
                    BinaryUtil.toBase64String(targetImage.getBytes()),
                    BinaryUtil.toBase64String(bucketName.getBytes()));
            System.out.println(sbStyle.toString());
            ProcessObjectRequest request = new ProcessObjectRequest(bucketName, sourceImage, sbStyle.toString());
            GenericResult processResult = ossClient.processObject(request);
            String json = IOUtils.readStreamAsString(processResult.getResponse().getContent(), "UTF-8");
            processResult.getResponse().getContent().close();
            System.out.println(json);
        } catch (OSSException oe) {
            System.out.println("Caught an OSSException, which means your request made it to OSS, "
                    + "but was rejected with an error response for some reason.");
            System.out.println("Error Message:" + oe.getErrorMessage());
            System.out.println("Error Code:" + oe.getErrorCode());
            System.out.println("Request ID:" + oe.getRequestId());
            System.out.println("Host ID:" + oe.getHostId());
        } catch (ClientException ce) {
            System.out.println("Caught an ClientException, which means the client encountered "
                    + "a serious internal problem while trying to communicate with OSS, "
                    + "such as not being able to access the network.");
            System.out.println("Error Message:" + ce.getMessage());
        } finally {
            if (ossClient != null) {
                ossClient.shutdown();
            }
        }
    }
}

Générer une URL d'objet signée incluant des paramètres IMG

Les URL des objets privés doivent être signées. Il est impossible d'ajouter des paramètres IMG à la fin d'une URL signée. Pour traiter un objet privé, intégrez les paramètres IMG à la signature. L'exemple de code suivant montre comment ajouter des paramètres IMG à une signature :

import com.aliyun.oss.*;
import com.aliyun.oss.common.auth.*;
import com.aliyun.oss.common.comm.SignVersion;
import com.aliyun.oss.model.GeneratePresignedUrlRequest;
import java.net.URL;
import java.util.Date;

public class Demo {
    public static void main(String[] args) throws Throwable {
        // In this example, the endpoint of the China (Hangzhou) region is used. Specify your actual endpoint. 
        String endpoint = "https://oss-cn-hangzhou.aliyuncs.com";
        // Obtain access credentials from environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured. 
        EnvironmentVariableCredentialsProvider credentialsProvider = CredentialsProviderFactory.newEnvironmentVariableCredentialsProvider();
        // Specify the name of the bucket. Example: examplebucket. 
        String bucketName = "examplebucket";
        // Specify the full path of the object. Do not include the bucket name in the full path. 
        String objectName = "exampleobject.jpg";
        // Specify the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the region to cn-hangzhou.
        String region = "cn-hangzhou";

        // Create an OSSClient instance.
        // Call the shutdown method to release resources when the OSSClient is no longer in use. 
        ClientBuilderConfiguration clientBuilderConfiguration = new ClientBuilderConfiguration();
        clientBuilderConfiguration.setSignatureVersion(SignVersion.V4);        
        OSS ossClient = OSSClientBuilder.create()
        .endpoint(endpoint)
        .credentialsProvider(credentialsProvider)
        .clientConfiguration(clientBuilderConfiguration)
        .region(region)               
        .build();

        try {
            // Resize the image to a height and width of 100 pixels, and rotate the image 90 degrees. 
            String style = "image/resize,m_fixed,w_100,h_100/rotate,90";
            // Set the validity period of the signed URL to 10 minutes. (The maximum validity period is 32400 seconds.)
            Date expiration = new Date(new Date().getTime() + 1000 * 60 * 10 );
            GeneratePresignedUrlRequest req = new GeneratePresignedUrlRequest(bucketName, objectName, HttpMethod.GET);
            req.setExpiration(expiration);
            req.setProcess(style);
            URL signedUrl = ossClient.generatePresignedUrl(req);
            System.out.println(signedUrl);
        } catch (OSSException oe) {
            System.out.println("Caught an OSSException, which means your request made it to OSS, "
                    + "but was rejected with an error response for some reason.");
            System.out.println("Error Message:" + oe.getErrorMessage());
            System.out.println("Error Code:" + oe.getErrorCode());
            System.out.println("Request ID:" + oe.getRequestId());
            System.out.println("Host ID:" + oe.getHostId());
        } catch (ClientException ce) {
            System.out.println("Caught an ClientException, which means the client encountered "
                    + "a serious internal problem while trying to communicate with OSS, "
                    + "such as not being able to access the network.");
            System.out.println("Error Message:" + ce.getMessage());
        } finally {
            if (ossClient != null) {
                ossClient.shutdown();
            }
        }
    }
}

Références

Pour plus d'informations sur les paramètres IMG pris en charge, consultez Présentation.
Pour obtenir le code d'exemple complet pour IMG, visitez GitHub.