Change the dataset_transform_fn argument in InputReader's constructor to transform_and_batch_fn.

PiperOrigin-RevId: 323013252

official/core/input_reader.py

@@ -32,7 +32,8 @@ class InputReader:
                dataset_fn=tf.data.TFRecordDataset,
                decoder_fn: Optional[Callable[..., Any]] = None,
                parser_fn: Optional[Callable[..., Any]] = None,
-               dataset_transform_fn: Optional[Callable[[tf.data.Dataset],
+               transform_and_batch_fn: Optional[Callable[
+                   [tf.data.Dataset, Optional[tf.distribute.InputContext]],
                    tf.data.Dataset]] = None,
                postprocess_fn: Optional[Callable[..., Any]] = None):
     """Initializes an InputReader instance.
@@ -48,9 +49,12 @@ class InputReader:
       parser_fn: An optional `callable` that takes the decoded raw tensors dict
         and parse them into a dictionary of tensors that can be consumed by the
         model. It will be executed after decoder_fn.
-      dataset_transform_fn: An optional `callable` that takes a
-        `tf.data.Dataset` object and returns a `tf.data.Dataset`. It will be
-        executed after parser_fn.
+      transform_and_batch_fn: An optional `callable` that takes a
+        `tf.data.Dataset` object and an optional `tf.distribute.InputContext` as
+        input, and returns a `tf.data.Dataset` object. It will be
+        executed after `parser_fn` to transform and batch the dataset; if None,
+        after `parser_fn` is executed, the dataset will be batched into
+        per-replica batch size.
       postprocess_fn: A optional `callable` that processes batched tensors. It
         will be executed after batching.
     """
@@ -101,7 +105,7 @@ class InputReader:
     self._dataset_fn = dataset_fn
     self._decoder_fn = decoder_fn
     self._parser_fn = parser_fn
-    self._dataset_transform_fn = dataset_transform_fn
+    self._transform_and_batch_fn = transform_and_batch_fn
     self._postprocess_fn = postprocess_fn
 
   def _read_sharded_files(
@@ -214,13 +218,13 @@ class InputReader:
     dataset = maybe_map_fn(dataset, self._decoder_fn)
     dataset = maybe_map_fn(dataset, self._parser_fn)
 
-    if self._dataset_transform_fn is not None:
-      dataset = self._dataset_transform_fn(dataset)
-
+    if self._transform_and_batch_fn is not None:
+      dataset = self._transform_and_batch_fn(dataset, input_context)
+    else:
       per_replica_batch_size = input_context.get_per_replica_batch_size(
           self._global_batch_size) if input_context else self._global_batch_size
-
       dataset = dataset.batch(
           per_replica_batch_size, drop_remainder=self._drop_remainder)
+
     dataset = maybe_map_fn(dataset, self._postprocess_fn)
     return dataset.prefetch(tf.data.experimental.AUTOTUNE)