Release 260111

tools/webcam/camera.py

@@ -0,0 +1,29 @@
+import av
+
+class Camera:
+  def __init__(self, cam_type_state, stream_type, camera_id):
+    try:
+      camera_id = int(camera_id)
+    except ValueError: # allow strings, ex: /dev/video0
+      pass
+    self.cam_type_state = cam_type_state
+    self.stream_type = stream_type
+    self.cur_frame_id = 0
+
+    self.container = av.open(camera_id)
+    assert self.container.streams.video, f"Can't open video stream for camera {camera_id}"
+    self.video_stream = self.container.streams.video[0]
+    self.W = self.video_stream.codec_context.width
+    self.H = self.video_stream.codec_context.height
+
+  @classmethod
+  def bgr2nv12(self, bgr):
+    frame = av.VideoFrame.from_ndarray(bgr, format='bgr24')
+    return frame.reformat(format='nv12').to_ndarray()
+
+  def read_frames(self):
+    for frame in self.container.decode(self.video_stream):
+      img = frame.to_rgb().to_ndarray()[:,:, ::-1] # convert to bgr24
+      yuv = Camera.bgr2nv12(img)
+      yield yuv.data.tobytes()
+    self.container.close()