@java.lang.Override
  public void writeTo(com.google.protobuf.CodedOutputStream output) throws java.io.IOException {
    if (!com.google.protobuf.GeneratedMessageV3.isStringEmpty(key_)) {
      com.google.protobuf.GeneratedMessageV3.writeString(output, 1, key_);
    }
    if (!com.google.protobuf.GeneratedMessageV3.isStringEmpty(uri_)) {
      com.google.protobuf.GeneratedMessageV3.writeString(output, 2, uri_);
    }
    if (((bitField0_ & 0x00000001) != 0)) {
      output.writeMessage(3, getPreprocessingConfig());
    }
    getUnknownFields().writeTo(output);
  }
<pre>
Preprocessing configurations.
</pre>

<code>.google.cloud.video.transcoder.v1.PreprocessingConfig preprocessing_config = 3;</code>
java-video-transcoder/proto-google-cloud-video-transcoder-v1/src/main/java/com/google/cloud/video/transcoder/v1/Input.java