trouble in making dataset

I have a dataset of type:
<BatchDataset shapes: ((None, 256, 256, 3), (None,)), types: (tf.float32, tf.int32)>
How do i convert it into a dataset of type:
<PrefetchDataset shapes: {image: (256, 256, 3), label: ()}, types: {image: tf.uint8, label: tf.int64}>
in tensorflow