Enable custom formatter in load_tts_samples

TTS/tts/datasets/__init__.py

@@ -1,7 +1,7 @@
 import sys
 from collections import Counter
 from pathlib import Path
-from typing import Dict, List, Tuple, Union
+from typing import Callable, Dict, List, Tuple, Union
 
 import numpy as np
 
@@ -10,6 +10,11 @@ from TTS.tts.datasets.formatters import *
 
 
 def split_dataset(items):
+    """Split a dataset into train and eval. Consider speaker distribution in multi-speaker training.
+
+    Args:
+        items (List[List]): A list of samples. Each sample is a list of `[audio_path, text, speaker_id]`.
+    """
     speakers = [item[-1] for item in items]
     is_multi_speaker = len(set(speakers)) > 1
     eval_split_size = min(500, int(len(items) * 0.01))
@@ -31,15 +36,23 @@ def split_dataset(items):
     return items[:eval_split_size], items[eval_split_size:]
 
 
-def load_tts_samples(datasets: Union[List[Dict], Dict], eval_split=True) -> Tuple[List[List], List[List]]:
-    """Parse the dataset, load the samples as a list and load the attention alignments if provided.
+def load_tts_samples(datasets: Union[List[Dict], Dict], eval_split=True, formatter: Callable=None) -> Tuple[List[List], List[List]]:
+    """Parse the dataset from the datasets config, load the samples as a List and load the attention alignments if provided.
+    If `formatter` is not None, apply the formatter to the samples else pick the formatter from the available ones based
+    on the dataset name.
 
     Args:
         datasets (List[Dict], Dict): A list of datasets or a single dataset dictionary. If multiple datasets are
             in the list, they are all merged.
+
         eval_split (bool, optional): If true, create a evaluation split. If an eval split provided explicitly, generate
             an eval split automatically. Defaults to True.
 
+        formatter (Callable, optional): The preprocessing function to be applied to create the list of samples. It
+            must take the root_path and the meta_file name and return a list of samples in the format of
+            `[[audio_path, text, speaker_id], ...]]`. See the available formatters in `TTS.tts.dataset.formatter` as
+            example. Defaults to None.
+
     Returns:
         Tuple[List[List], List[List]: training and evaluation splits of the dataset.
     """
@@ -53,14 +66,15 @@ def load_tts_samples(datasets: Union[List[Dict], Dict], eval_split=True) -> Tupl
         meta_file_train = dataset["meta_file_train"]
         meta_file_val = dataset["meta_file_val"]
         # setup the right data processor
-        preprocessor = _get_preprocessor_by_name(name)
+        if formatter is None:
+            formatter = _get_formatter_by_name(name)
         # load train set
-        meta_data_train = preprocessor(root_path, meta_file_train)
+        meta_data_train = formatter(root_path, meta_file_train)
         print(f" | > Found {len(meta_data_train)} files in {Path(root_path).resolve()}")
         # load evaluation split if set
         if eval_split:
             if meta_file_val:
-                meta_data_eval = preprocessor(root_path, meta_file_val)
+                meta_data_eval = formatter(root_path, meta_file_val)
             else:
                 meta_data_eval, meta_data_train = split_dataset(meta_data_train)
             meta_data_eval_all += meta_data_eval
@@ -90,7 +104,7 @@ def load_attention_mask_meta_data(metafile_path):
     return meta_data
 
 
-def _get_preprocessor_by_name(name):
+def _get_formatter_by_name(name):
     """Returns the respective preprocessing function."""
     thismodule = sys.modules[__name__]
     return getattr(thismodule, name.lower())