optimize unnecessary copy

livekit-rtc/livekit/rtc/_utils.py

@@ -40,8 +40,18 @@ def task_done_logger(task: asyncio.Task) -> None:
         return
 
 
-def get_address(mv: memoryview) -> int:
-    return ctypes.addressof(ctypes.c_char.from_buffer(mv))
+def get_address(data) -> int:
+    if isinstance(data, memoryview):
+        if not data.readonly:
+            return ctypes.addressof(ctypes.c_char.from_buffer(data))
+        data = data.obj
+    if isinstance(data, bytearray):
+        return ctypes.addressof(ctypes.c_char.from_buffer(data))
+    if isinstance(data, bytes):
+        addr = ctypes.cast(ctypes.c_char_p(data), ctypes.c_void_p).value
+        assert addr is not None
+        return addr
+    raise TypeError(f"expected bytes, bytearray, or memoryview, got {type(data)}")
 
 
 T = TypeVar("T")

livekit-rtc/livekit/rtc/audio_frame.py

@@ -49,19 +49,22 @@ def __init__(
         Raises:
             ValueError: If the length of `data` is smaller than the required size.
         """
-        data = memoryview(data).cast("B")
+        if isinstance(data, memoryview):
+            data = data.obj  # type: ignore[assignment]
 
-        if len(data) < num_channels * samples_per_channel * ctypes.sizeof(ctypes.c_int16):
+        min_size = num_channels * samples_per_channel * ctypes.sizeof(ctypes.c_int16)
+        data_len = len(data)
+
+        if data_len < min_size:
             raise ValueError(
                 "data length must be >= num_channels * samples_per_channel * sizeof(int16)"
             )
 
-        if len(data) % ctypes.sizeof(ctypes.c_int16) != 0:
+        if data_len % ctypes.sizeof(ctypes.c_int16) != 0:
             # can happen if data is bigger than needed
             raise ValueError("data length must be a multiple of sizeof(int16)")
 
-        n = len(data) // ctypes.sizeof(ctypes.c_int16)
-        self._data = (ctypes.c_int16 * n).from_buffer_copy(data)
+        self._data = data
 
         self._sample_rate = sample_rate
         self._num_channels = num_channels
@@ -97,7 +100,7 @@ def _from_owned_info(owned_info: proto_audio.OwnedAudioFrameBuffer) -> "AudioFra
 
     def _proto_info(self) -> proto_audio.AudioFrameBufferInfo:
         audio_info = proto_audio.AudioFrameBufferInfo()
-        audio_info.data_ptr = get_address(memoryview(self._data))
+        audio_info.data_ptr = get_address(self._data)
         audio_info.sample_rate = self.sample_rate
         audio_info.num_channels = self.num_channels
         audio_info.samples_per_channel = self.samples_per_channel

livekit-rtc/livekit/rtc/video_frame.py

@@ -51,7 +51,7 @@ def __init__(
         self._width = width
         self._height = height
         self._type = type
-        self._data = bytearray(data)
+        self._data = data
 
     @property
     def width(self) -> int: