@java.lang.Override
  public int getSerializedSize() {
    int size = memoizedSize;
    if (size != -1) return size;

    size = 0;
    if (!content_.isEmpty()) {
      size += com.google.protobuf.CodedOutputStream.computeBytesSize(1, content_);
    }
    if (((bitField0_ & 0x00000001) != 0)) {
      size += com.google.protobuf.CodedOutputStream.computeMessageSize(2, getSource());
    }
    size += getUnknownFields().getSerializedSize();
    memoizedSize = size;
    return size;
  }
<pre>
Google Cloud Storage image location, or publicly-accessible image
URL. If both `content` and `source` are provided for an image, `content`
takes precedence and is used to perform the image annotation request.
</pre>

<code>.google.cloud.vision.v1p2beta1.ImageSource source = 2;</code>
java-vision/proto-google-cloud-vision-v1p2beta1/src/main/java/com/google/cloud/vision/v1p2beta1/Image.java