[feat] update some feature

sync code of  fastrtc,
add text support through datachannel,
fix safari connect problem
support chat without camera or mic

backend/fastrtc/text_to_speech/__init__.py

@@ -0,0 +1,3 @@
+from .tts import KokoroTTSOptions, get_tts_model
+
+__all__ = ["get_tts_model", "KokoroTTSOptions"]

backend/fastrtc/text_to_speech/test_tts.py

@@ -0,0 +1,13 @@
+from fastrtc.text_to_speech.tts import get_tts_model
+
+
+def test_tts_long_prompt():
+    model = get_tts_model()
+    prompt = "It may be that this communication will be considered as a madman's freak but at any rate it must be admitted that in its clearness and frankness it left nothing to be desired The serious part of it was that the Federal Government had undertaken to treat a sale by auction as a valid concession of these undiscovered territories Opinions on the matter were many Some readers saw in it only one of those prodigious outbursts of American humbug which would exceed the limits of puffism if the depths of human credulity were not unfathomable"
+
+    for i, chunk in enumerate(model.stream_tts_sync(prompt)):
+        print(f"Chunk {i}: {chunk[1].shape}")
+
+
+if __name__ == "__main__":
+    test_tts_long_prompt()

backend/fastrtc/text_to_speech/tts.py

@@ -0,0 +1,135 @@
+import asyncio
+import re
+from dataclasses import dataclass
+from functools import lru_cache
+from typing import AsyncGenerator, Generator, Literal, Protocol
+
+import numpy as np
+from huggingface_hub import hf_hub_download
+from numpy.typing import NDArray
+
+
+class TTSOptions:
+    pass
+
+
+class TTSModel(Protocol):
+    def tts(self, text: str) -> tuple[int, NDArray[np.float32]]: ...
+
+    async def stream_tts(
+        self, text: str, options: TTSOptions | None = None
+    ) -> AsyncGenerator[tuple[int, NDArray[np.float32]], None]: ...
+
+    def stream_tts_sync(
+        self, text: str, options: TTSOptions | None = None
+    ) -> Generator[tuple[int, NDArray[np.float32]], None, None]: ...
+
+
+@dataclass
+class KokoroTTSOptions(TTSOptions):
+    voice: str = "af_heart"
+    speed: float = 1.0
+    lang: str = "en-us"
+
+
+@lru_cache
+def get_tts_model(model: Literal["kokoro"] = "kokoro") -> TTSModel:
+    m = KokoroTTSModel()
+    m.tts("Hello, world!")
+    return m
+
+
+class KokoroFixedBatchSize:
+    # Source: https://github.com/thewh1teagle/kokoro-onnx/issues/115#issuecomment-2676625392
+    def _split_phonemes(self, phonemes: str) -> list[str]:
+        MAX_PHONEME_LENGTH = 510
+        max_length = MAX_PHONEME_LENGTH - 1
+        batched_phonemes = []
+        while len(phonemes) > max_length:
+            # Find best split point within limit
+            split_idx = max_length
+
+            # Try to find the last period before max_length
+            period_idx = phonemes.rfind(".", 0, max_length)
+            if period_idx != -1:
+                split_idx = period_idx + 1  # Include period
+
+            else:
+                # Try other punctuation
+                match = re.search(
+                    r"[!?;,]", phonemes[:max_length][::-1]
+                )  # Search backwards
+                if match:
+                    split_idx = max_length - match.start()
+
+                else:
+                    # Try last space
+                    space_idx = phonemes.rfind(" ", 0, max_length)
+                    if space_idx != -1:
+                        split_idx = space_idx
+
+            # If no good split point is found, force split at max_length
+            chunk = phonemes[:split_idx].strip()
+            batched_phonemes.append(chunk)
+
+            # Move to the next part
+            phonemes = phonemes[split_idx:].strip()
+
+        # Add remaining phonemes
+        if phonemes:
+            batched_phonemes.append(phonemes)
+        return batched_phonemes
+
+
+class KokoroTTSModel(TTSModel):
+    def __init__(self):
+        from kokoro_onnx import Kokoro
+
+        self.model = Kokoro(
+            model_path=hf_hub_download("fastrtc/kokoro-onnx", "kokoro-v1.0.onnx"),
+            voices_path=hf_hub_download("fastrtc/kokoro-onnx", "voices-v1.0.bin"),
+        )
+
+        self.model._split_phonemes = KokoroFixedBatchSize()._split_phonemes
+
+    def tts(
+        self, text: str, options: KokoroTTSOptions | None = None
+    ) -> tuple[int, NDArray[np.float32]]:
+        options = options or KokoroTTSOptions()
+        a, b = self.model.create(
+            text, voice=options.voice, speed=options.speed, lang=options.lang
+        )
+        return b, a
+
+    async def stream_tts(
+        self, text: str, options: KokoroTTSOptions | None = None
+    ) -> AsyncGenerator[tuple[int, NDArray[np.float32]], None]:
+        options = options or KokoroTTSOptions()
+
+        sentences = re.split(r"(?<=[.!?])\s+", text.strip())
+
+        for s_idx, sentence in enumerate(sentences):
+            if not sentence.strip():
+                continue
+
+            chunk_idx = 0
+            async for chunk in self.model.create_stream(
+                sentence, voice=options.voice, speed=options.speed, lang=options.lang
+            ):
+                if s_idx != 0 and chunk_idx == 0:
+                    yield chunk[1], np.zeros(chunk[1] // 7, dtype=np.float32)
+                chunk_idx += 1
+                yield chunk[1], chunk[0]
+
+    def stream_tts_sync(
+        self, text: str, options: KokoroTTSOptions | None = None
+    ) -> Generator[tuple[int, NDArray[np.float32]], None, None]:
+        loop = asyncio.new_event_loop()
+
+        # Use the new loop to run the async generator
+        iterator = self.stream_tts(text, options).__aiter__()
+        while True:
+            try:
+                yield loop.run_until_complete(iterator.__anext__())
+            except StopAsyncIteration:
+                break