@java.lang.Override
  public void writeTo(com.google.protobuf.CodedOutputStream output) throws java.io.IOException {
    if (((bitField0_ & 0x00000001) != 0)) {
      output.writeMessage(1, getInputConfig());
    }
    for (int i = 0; i < features_.size(); i++) {
      output.writeMessage(2, features_.get(i));
    }
    if (((bitField0_ & 0x00000002) != 0)) {
      output.writeMessage(3, getImageContext());
    }
    if (((bitField0_ & 0x00000004) != 0)) {
      output.writeMessage(4, getOutputConfig());
    }
    getUnknownFields().writeTo(output);
  }
<pre>
Required. The desired output location and metadata (e.g. format).
</pre>

<code>.google.cloud.vision.v1p3beta1.OutputConfig output_config = 4;</code>
java-vision/proto-google-cloud-vision-v1p3beta1/src/main/java/com/google/cloud/vision/v1p3beta1/AsyncAnnotateFileRequest.java