Image processing (Android SDK)

Usage notes

• Before you run the sample code in this topic, you must create an OSSClient instance by using methods such as using a custom domain name or Security Token Service (STS). For more information, see Initialization (Android SDK).

Usage of IMG

• Anonymous access

  String url = oss.presignPublicObjectURL(testBucket, testObject);
          OSSLog.logDebug("signPublicURL", "get url: " + url);
  Then, append the x-oss-process parameter to the URL. The parameter's value specifies the image processing operation.

• Authorized access

  To process an image using the SDK, call the request.setxOssProcess() method to set the processing parameters for the download request. The following code provides an example:

  // Create a request to download an image.
  // Specify the bucket name (for example, examplebucket) and the object full path (for example, exampledir/exampleobject.txt). The object full path cannot contain the bucket name.
  GetObjectRequest request = new GetObjectRequest("examplebucket", "exampledir/exampleobject.txt");
  
  // Process the image.
  request.setxOssProcess("image/resize,m_fixed,w_100,h_100");
  
  OSSAsyncTask task = oss.asyncGetObject(get, new OSSCompletedCallback<GetObjectRequest, GetObjectResult>() {
      @Override
      public void onSuccess(GetObjectRequest request, GetObjectResult result) {
          // The request is successful.
          InputStream inputStream = result.getObjectContent();
  
          byte[] buffer = new byte[2048];
          int len;
  
          try {
              while ((len = inputStream.read(buffer)) != -1) {
                  // Process the downloaded data.
              }
          } catch (IOException e) {
              e.printStackTrace();
          }
      }
  
      @Override
      public void onFailure(GetObjectRequest request, ClientException clientException, ServiceException serviceException) {
          // Handle the exception. You can add your own exception handling logic.
      }
  });

  Note

  To perform other operations on the image, replace the argument passed to request.setxOssProcess().

• Access by using the OSS SDK

  GetObjectRequest request = new GetObjectRequest("bucket-name", "image-name");
  request.setxOssProcess("image/resize,m_lfit,w_100,h_100");  // Set image processing parameters.
  OSSAsyncTask task = oss.asyncGetObject(request, getCallback);

Save processed images

The following sample code provides an example on how to save processed images:

// fromBucket and toBucket specify the source and destination bucket names.
// fromObjectKey and toObjectKey specify the source and destination object names. The names must be full paths that include the file extension, for example, abc/efg/123.jpg.
// action specifies the image processing operation, such as "image/resize,m_lfit,w_100,h_100".
ImagePersistRequest request = new ImagePersistRequest(fromBucket,fromObjectKey,toBucket,toObjectKey,action);

        OSSAsyncTask task = oss.asyncImagePersist(request, new OSSCompletedCallback<ImagePersistRequest, ImagePersistResult>() {
            @Override
            public void onSuccess(ImagePersistRequest request, ImagePersistResult result) {
                // Success callback
                log.i("info", "Success");
            }

            @Override
            public void onFailure(ImagePersistRequest request, ClientException clientException, ServiceException serviceException) {
              // The request failed.
              if (clientException != null) {
                  // A client-side exception occurred, such as a network error.
                  clientException.printStackTrace();
              }
              if (serviceException != null) {
                  // A server-side exception occurred.
                  Log.e("ErrorCode", serviceException.getErrorCode());
                  Log.e("RequestId", serviceException.getRequestId());
                  Log.e("HostId", serviceException.getHostId());
                  Log.e("RawMessage", serviceException.getRawMessage());
              }
            }
        });

Image processing tool

Use the ImageStyleViewer visual tool to preview the results of Image Processing in real time.

References

• For more information about the supported IMG parameters, see IMG parameters.

• For the complete sample code that is used to perform IMG operations, visit GitHub.

• For more information about how to initialize an OSSClient instance, see Initialization.