add a v4l2 thing

vipc2v4l2emu.py

@@ -0,0 +1,39 @@
+from compressed_vipc_track import VisionIpcTrack, W, H
+import asyncio
+import pyvirtualcam
+import sys
+
+cam = pyvirtualcam.Camera(width=W, height=H, fps=20)
+
+def work(frame):
+    frame = frame.to_ndarray(format='bgr24')
+    cam.send(frame)
+    cam.sleep_until_next_frame()
+        
+if __name__ == "__main__":
+    from time import time_ns
+    import sys
+
+    async def test():
+        frame_count=0
+        start_time=time_ns()
+        track = VisionIpcTrack("roadEncodeData", "tici")
+        while True:
+            frame = await track.recv()
+            work(frame)
+            now = time_ns()
+            playtime = now - start_time
+            playtime_sec = playtime * 0.000000001
+            if playtime_sec >= 1:
+                print(f'fps: {frame_count}')
+                frame_count = 0
+                start_time = time_ns()
+            else:
+                frame_count+=1
+
+    # Run event loop
+    loop = asyncio.new_event_loop()
+    try:
+        loop.run_until_complete(test())
+    except KeyboardInterrupt:
+        sys.exit(0)