Add stream helper utilities and IVF frame iterator (#1082)

* Add stream helper utilities and IVF frame iterator

* fix lint

* some cosmetics

* fix lint

* changes

* improve test

* improve types and test

* add todo for better bitrate calculation

facefusion/apis/stream_helper.py

@@ -1,11 +1,18 @@
 import asyncio
-from typing import Tuple
+import math
+import os
+import subprocess
+from typing import Iterator, Optional, Tuple, cast
 
 from aiortc import MediaStreamTrack, QueuedVideoStreamTrack, RTCPeerConnection, RTCRtpSender
 from aiortc.mediastreams import MediaStreamError
 from av import VideoFrame
+from starlette.datastructures import Headers
+from starlette.types import Scope
 
+from facefusion.common_helper import is_linux, is_macos
 from facefusion.streamer import process_vision_frame
+from facefusion.types import Resolution, StreamBuffer, WebSocketStreamMode
 
 
 def process_stream_frame(target_stream_frame : VideoFrame) -> VideoFrame:
@@ -42,3 +49,62 @@ def on_video_track(rtc_connection : RTCPeerConnection, output_track : QueuedVide
 
 	if target_track.kind == 'video':
 		asyncio.create_task(process_and_enqueue(target_track, output_track))
+
+
+def calculate_bitrate(resolution : Resolution) -> int: # TODO : improve the bitrate calculation
+	pixel_total = resolution[0] * resolution[1]
+	bitrate_factor = 3500 / math.sqrt(1920 * 1080)
+	return max(400, round(math.sqrt(pixel_total) * bitrate_factor))
+
+
+def calculate_buffer_size(resolution : Resolution) -> int:
+	return calculate_bitrate(resolution) * 2
+
+
+def get_websocket_stream_mode(scope : Scope) -> Optional[WebSocketStreamMode]:
+	protocol_header = Headers(scope = scope).get('Sec-WebSocket-Protocol')
+
+	if protocol_header:
+		for protocol in protocol_header.split(','):
+			websocket_stream_mode = protocol.strip()
+
+			if websocket_stream_mode in [ 'image', 'video' ]:
+				return cast(WebSocketStreamMode, websocket_stream_mode)
+
+	return None
+
+
+def read_pipe_buffer(pipe_handle : int, size : int) -> Optional[bytes]:
+	byte_buffer = bytearray()
+	frame_data = os.read(pipe_handle, size - len(byte_buffer))
+
+	while frame_data:
+		byte_buffer += frame_data
+
+		if len(byte_buffer) == size:
+			return bytes(byte_buffer)
+
+		frame_data = os.read(pipe_handle, size - len(byte_buffer))
+
+	return None
+
+
+def forward_stream_frame(process : subprocess.Popen[bytes]) -> Iterator[StreamBuffer]:
+	pipe_handle = process.stdout.fileno()
+
+	if is_linux() or is_macos():
+		os.set_blocking(pipe_handle, True)
+
+	header = read_pipe_buffer(pipe_handle, 32)
+
+	if header:
+		frame_header = read_pipe_buffer(pipe_handle, 12)
+
+		while frame_header:
+			frame_size = int.from_bytes(frame_header[0:4], 'little')
+			frame_data = read_pipe_buffer(pipe_handle, frame_size)
+
+			if frame_data:
+				yield frame_data
+
+			frame_header = read_pipe_buffer(pipe_handle, 12)

facefusion/types.py

@@ -264,6 +264,8 @@ BenchmarkCycleSet = TypedDict('BenchmarkCycleSet',
 
 WebcamMode = Literal['inline', 'udp', 'v4l2']
 StreamMode = Literal['udp', 'v4l2']
+WebSocketStreamMode = Literal['image', 'video']
+StreamBuffer : TypeAlias = bytes
 
 RtcOfferSet = TypedDict('RtcOfferSet',
 {