docs: private synchronized Producer<CloseableReference<CloseableImage>> getBitmapPrepareSequence(
        Producer<CloseableReference<CloseableImage>> inputProducer) {
      Producer<CloseableReference<CloseableImage>> bitmapPrepareProducer =
          mBitmapPrepareSequences.get(inputProducer);
  
      if (bitmapPrepareProducer == null) {
        bitmapPrepareProducer = mProducerFactory.newBitmapPrepareProducer(inputProducer);
        mBitmapPrepareSequences.put(inputProducer, bitmapPrepareProducer);
      }
  
      return bitmapPrepareProducer;
    }