remove thread lock

app.py

@@ -15,8 +15,6 @@ class Session:
 app = Flask(__name__)
 PORT = int(os.environ.get("PORT", 5000))
 
-lock = threading.Lock()
-
 sessions: set[Session] = set()
 
 def frame_processor(session_id: str):
@@ -44,18 +42,17 @@ def frame_processor(session_id: str):
                 cap.set(cv2.CAP_PROP_POS_FRAMES, 0)
                 continue
             else:
-                with lock:
-                    if session.show_fps:
-                        text = f"{session_id}: {session.measured_fps:.0f}"
-                        font = cv2.FONT_HERSHEY_SIMPLEX
-                        font_scale = 1
-                        thickness = 2
-                        color = (0, 255, 0)
-                        (text_width, text_height), _ = cv2.getTextSize(text, font, font_scale, thickness)
-                        x = frame.shape[1] - text_width - 10
-                        y = 30
-                        cv2.putText(frame, text, (x, y), font, font_scale, color, thickness, cv2.LINE_AA)
-                    session.latest_frame = frame
+                if session.show_fps:
+                    text = f"{session_id}: {session.measured_fps:.0f}"
+                    font = cv2.FONT_HERSHEY_SIMPLEX
+                    font_scale = 1
+                    thickness = 2
+                    color = (0, 255, 0)
+                    (text_width, text_height), _ = cv2.getTextSize(text, font, font_scale, thickness)
+                    x = frame.shape[1] - text_width - 10
+                    y = 30
+                    cv2.putText(frame, text, (x, y), font, font_scale, color, thickness, cv2.LINE_AA)
+                session.latest_frame = frame
 
             # measure FPS
             frame_count += 1
@@ -82,11 +79,10 @@ def stream_mjpeg(session_id: str):
         while True:
             if session.latest_frame is None:
                 continue
-            with lock:
-                encode_param = [int(cv2.IMWRITE_JPEG_QUALITY), 50]
-                ret, jpeg = cv2.imencode(".jpg", session.latest_frame, encode_param)
-                frame_bytes = jpeg.tobytes() if ret else None
-                # print(f"frame filesize: {len(frame_bytes) / (1024 * 1024):.4f} MB")
+            encode_param = [int(cv2.IMWRITE_JPEG_QUALITY), 50]
+            ret, jpeg = cv2.imencode(".jpg", session.latest_frame, encode_param)
+            frame_bytes = jpeg.tobytes() if ret else None
+            # print(f"frame filesize: {len(frame_bytes) / (1024 * 1024):.4f} MB")
             if frame_bytes is not None:
                 yield (b"--frame\r\n"b"Content-Type: image/jpeg\r\n\r\n" + frame_bytes + b"\r\n")