Merge pull request #688 from qtangs/patch-1

Fix for exception on streaming on last chunk - copied from coqui-ai/TTS#3160

tortoise/api_fast.py

@@ -277,17 +277,28 @@ def tts_with_preset(self, text, preset='fast', **kwargs):
         settings.update(kwargs) # allow overriding of preset settings with kwargs
         for audio_frame in self.tts(text, **settings):
             yield audio_frame
-    # taken from here https://github.com/coqui-ai/TTS/blob/d21f15cc850788f9cdf93dac0321395138665287/TTS/tts/models/xtts.py#L666
+    # taken from here https://github.com/coqui-ai/TTS/blob/b4c552a112fd4c5f3477f439882eb43c2e2ce85f/TTS/tts/models/xtts.py#L600
     def handle_chunks(self, wav_gen, wav_gen_prev, wav_overlap, overlap_len):
         """Handle chunk formatting in streaming mode"""
         wav_chunk = wav_gen[:-overlap_len]
         if wav_gen_prev is not None:
             wav_chunk = wav_gen[(wav_gen_prev.shape[0] - overlap_len) : -overlap_len]
         if wav_overlap is not None:
-            crossfade_wav = wav_chunk[:overlap_len]
-            crossfade_wav = crossfade_wav * torch.linspace(0.0, 1.0, overlap_len).to(crossfade_wav.device)
-            wav_chunk[:overlap_len] = wav_overlap * torch.linspace(1.0, 0.0, overlap_len).to(wav_overlap.device)
-            wav_chunk[:overlap_len] += crossfade_wav
+            # cross fade the overlap section
+            if overlap_len > len(wav_chunk):
+                # wav_chunk is smaller than overlap_len, pass on last wav_gen
+                if wav_gen_prev is not None:
+                    wav_chunk = wav_gen[(wav_gen_prev.shape[0] - overlap_len):]
+                else:
+                    # not expecting will hit here as problem happens on last chunk
+                    wav_chunk = wav_gen[-overlap_len:]
+                return wav_chunk, wav_gen, None
+            else:
+                crossfade_wav = wav_chunk[:overlap_len]
+                crossfade_wav = crossfade_wav * torch.linspace(0.0, 1.0, overlap_len).to(crossfade_wav.device)
+                wav_chunk[:overlap_len] = wav_overlap * torch.linspace(1.0, 0.0, overlap_len).to(wav_overlap.device)
+                wav_chunk[:overlap_len] += crossfade_wav
+
         wav_overlap = wav_gen[-overlap_len:]
         wav_gen_prev = wav_gen
         return wav_chunk, wav_gen_prev, wav_overlap