Merge pull request #84 from jaeyoo/patch-2

🚀 📝 Add TFLite-convertible TFFastSpeech

Author: dathudeptrai

tensorflow_tts/models/fastspeech.py

@@ -573,14 +573,14 @@ def call(self, inputs, training=False):
 class TFFastSpeechLengthRegulator(tf.keras.layers.Layer):
     """FastSpeech lengthregulator module."""
 
-    def __init__(self, config, **kwargs):
+    def __init__(self, config, enable_tflite_convertible = False, **kwargs):
         """Init variables."""
         super().__init__(**kwargs)
         self.config = config
+        self.enable_tflite_convertible = enable_tflite_convertible
 
     def call(self, inputs, training=False):
         """Call logic.
-
         Args:
             1. encoder_hidden_states, Tensor (float32) shape [batch_size, length, hidden_size]
             2. durations_gt, Tensor (float32/int32) shape [batch_size, length]
@@ -601,75 +601,93 @@ def _length_regulator(self, encoder_hidden_states, durations_gt):
         hidden_size = input_shape[-1]
 
         # initialize output hidden states and encoder masking.
-        outputs = tf.zeros(shape=[0, max_durations, hidden_size], dtype=tf.float32)
-        encoder_masks = tf.zeros(shape=[0, max_durations], dtype=tf.int32)
-
-        def condition(
-            i,
-            batch_size,
-            outputs,
-            encoder_masks,
-            encoder_hidden_states,
-            durations_gt,
-            max_durations,
-        ):
-            return tf.less(i, batch_size)
-
-        def body(
-            i,
-            batch_size,
-            outputs,
-            encoder_masks,
-            encoder_hidden_states,
-            durations_gt,
-            max_durations,
-        ):
-            repeats = durations_gt[i]
+        if self.enable_tflite_convertible:
+            # There is only 1 batch in inference, so we don't have to use
+            # `tf.While` op with 3-D output tensor.
+            repeats = durations_gt[0]
             real_length = tf.reduce_sum(repeats)
             pad_size = max_durations - real_length
+            # masks : [max_durations]
             masks = tf.sequence_mask([real_length], max_durations, dtype=tf.int32)
             repeat_encoder_hidden_states = tf.repeat(
-                encoder_hidden_states[i], repeats=repeats, axis=0
+                encoder_hidden_states[0], repeats=repeats, axis=0
             )
             repeat_encoder_hidden_states = tf.expand_dims(
                 tf.pad(repeat_encoder_hidden_states, [[0, pad_size], [0, 0]]), 0
-            )  # [1, max_durations, hidden_size]
-            outputs = tf.concat([outputs, repeat_encoder_hidden_states], axis=0)
-            encoder_masks = tf.concat([encoder_masks, masks], axis=0)
-            return [
-                i + 1,
+            )  # [1, max_durations, hidden_size] 
+
+            outputs = repeat_encoder_hidden_states
+            encoder_masks = masks
+        else:
+            outputs = tf.zeros(shape=[0, max_durations, hidden_size], dtype=tf.float32)
+            encoder_masks = tf.zeros(shape=[0, max_durations], dtype=tf.int32)
+
+            def condition(
+                i,
                 batch_size,
                 outputs,
                 encoder_masks,
                 encoder_hidden_states,
                 durations_gt,
                 max_durations,
-            ]
+            ):
+                return tf.less(i, batch_size)
 
-        # initialize iteration i.
-        i = tf.constant(0, dtype=tf.int32)
-        _, _, outputs, encoder_masks, _, _, _, = tf.while_loop(
-            condition,
-            body,
-            [
+            def body(
                 i,
                 batch_size,
                 outputs,
                 encoder_masks,
                 encoder_hidden_states,
                 durations_gt,
                 max_durations,
-            ],
-            shape_invariants=[
-                i.get_shape(),
-                batch_size.get_shape(),
-                tf.TensorShape([None, None, self.config.hidden_size]),
-                tf.TensorShape([None, None]),
-                encoder_hidden_states.get_shape(),
-                durations_gt.get_shape(),
-                max_durations.get_shape(),
-            ],
-        )
+            ):
+                repeats = durations_gt[i]
+                real_length = tf.reduce_sum(repeats)
+                pad_size = max_durations - real_length
+                masks = tf.sequence_mask([real_length], max_durations, dtype=tf.int32)
+                repeat_encoder_hidden_states = tf.repeat(
+                    encoder_hidden_states[i], repeats=repeats, axis=0
+                )
+                repeat_encoder_hidden_states = tf.expand_dims(
+                    tf.pad(repeat_encoder_hidden_states, [[0, pad_size], [0, 0]]), 0
+                )  # [1, max_durations, hidden_size]
+                outputs = tf.concat([outputs, repeat_encoder_hidden_states], axis=0)
+                encoder_masks = tf.concat([encoder_masks, masks], axis=0)
+                return [
+                    i + 1,
+                    batch_size,
+                    outputs,
+                    encoder_masks,
+                    encoder_hidden_states,
+                    durations_gt,
+                    max_durations,
+                ]
+
+            # initialize iteration i.
+            i = tf.constant(0, dtype=tf.int32)
+            _, _, outputs, encoder_masks, _, _, _, = tf.while_loop(
+                condition,
+                body,
+                [
+                    i,
+                    batch_size,
+                    outputs,
+                    encoder_masks,
+                    encoder_hidden_states,
+                    durations_gt,
+                    max_durations,
+                ],
+                shape_invariants=[
+                    i.get_shape(),
+                    batch_size.get_shape(),
+                    tf.TensorShape([None, None, self.config.hidden_size]),
+                    tf.TensorShape([None, None]),
+                    encoder_hidden_states.get_shape(),
+                    durations_gt.get_shape(),
+                    max_durations.get_shape(),
+                ],
+            )
 
         return outputs, encoder_masks
 
@@ -799,3 +817,59 @@ def inference(self, input_ids, attention_mask, speaker_ids, speed_ratios):
 
         outputs = (mel_before, mel_after, duration_outputs)
         return outputs
+
+    @tf.function(
+        experimental_relax_shapes=True,
+        input_signature=[
+            tf.TensorSpec(shape=[1, None], dtype=tf.int32),
+            tf.TensorSpec(shape=[1, None], dtype=tf.bool),
+            tf.TensorSpec(shape=[1,], dtype=tf.int32),
+            tf.TensorSpec(shape=[1,], dtype=tf.float32),
+        ],
+    )
+    def inference_tflite(self, input_ids, attention_mask, speaker_ids, speed_ratios):
+        """Call logic."""
+        embedding_output = self.embeddings([input_ids, speaker_ids], training=False)
+        encoder_output = self.encoder(
+            [embedding_output, attention_mask], training=False
+        )
+        last_encoder_hidden_states = encoder_output[0]
+
+        # duration predictor, here use last_encoder_hidden_states, u can use more hidden_states layers
+        # rather than just use last_hidden_states of encoder for duration_predictor.
+        duration_outputs = self.duration_predictor(
+            [last_encoder_hidden_states, attention_mask]
+        )  # [batch_size, length]
+        duration_outputs = tf.math.exp(duration_outputs) - 1.0
+
+        if speed_ratios is None:
+            speed_ratios = tf.convert_to_tensor(np.array([1.0]), dtype=tf.float32)
+
+        duration_outputs = tf.cast(
+            tf.math.round(duration_outputs * speed_ratios), tf.int32
+        )
+
+        length_regulator_outputs, encoder_masks = self.length_regulator(
+            [last_encoder_hidden_states, duration_outputs], training=False
+        )
+
+        # create decoder positional embedding
+        decoder_pos = tf.range(
+            1, tf.shape(length_regulator_outputs)[1] + 1, dtype=tf.int32
+        )
+        masked_decoder_pos = tf.expand_dims(decoder_pos, 0) * encoder_masks
+
+        decoder_output = self.decoder(
+            [length_regulator_outputs, speaker_ids, encoder_masks, masked_decoder_pos],
+            training=False,
+        )
+        last_decoder_hidden_states = decoder_output[0]
+
+        # here u can use sum or concat more than 1 hidden states layers from decoder.
+        mel_before = self.mel_dense(last_decoder_hidden_states)
+        mel_after = (
+            self.postnet([mel_before, encoder_masks], training=False) + mel_before
+        )
+
+        outputs = (mel_before, mel_after, duration_outputs)
+        return outputs