parler-tts support (#2431)

* Start sketching parler-tts support.

* Implement the attention.

* Add the example code.

* Fix the example.

* Add the description + t5 encode it.

* More of the parler forward pass.

* Fix the positional embeddings.

* Support random sampling in generation.

* Handle EOS.

* Add the python decoder.

* Proper causality mask.

candle-examples/examples/parler-tts/decode.py

@@ -0,0 +1,29 @@
+import torch
+import torchaudio
+from safetensors.torch import load_file
+from parler_tts import DACModel
+
+tensors = load_file("out.safetensors")
+dac_model = DACModel.from_pretrained("parler-tts/dac_44khZ_8kbps")
+output_ids = tensors["codes"][None, None]
+print(output_ids, "\n", output_ids.shape)
+batch_size = 1
+with torch.no_grad():
+    output_values = []
+    for sample_id in range(batch_size):
+        sample = output_ids[:, sample_id]
+        sample_mask = (sample >= dac_model.config.codebook_size).sum(dim=(0, 1)) == 0
+        if sample_mask.sum() > 0:
+            sample = sample[:, :, sample_mask]
+            sample = dac_model.decode(sample[None, ...], [None]).audio_values
+            output_values.append(sample.transpose(0, 2))
+        else:
+            output_values.append(torch.zeros((1, 1, 1)).to(dac_model.device))
+    output_lengths = [audio.shape[0] for audio in output_values]
+    pcm = (
+        torch.nn.utils.rnn.pad_sequence(output_values, batch_first=True, padding_value=0)
+        .squeeze(-1)
+        .squeeze(-1)
+    )
+print(pcm.shape, pcm.dtype)
+torchaudio.save("out.wav", pcm.cpu(), sample_rate=44100)