refactor: optimize frame processing by removing sleep

app.py

@@ -38,48 +38,43 @@ def frame_processor(session_id: str):
         next_frame_time = time.time()
         
         while True:
-            ret, frame = cap.read()
-
-            # measure FPS
-            frame_count += 1
-            now = time.time()
-            if now - last_time >= rolling_duration:  
-                session.measured_fps = frame_count / (now - last_time)
-                session.cpu_usage = psutil.cpu_percent(interval=None)
-                frame_count = 0
-                last_time = now
-
-            if not ret:
-                cap.set(cv2.CAP_PROP_POS_FRAMES, 0)
-                continue
-            else:
-                if session.show_stats:
-                    font = cv2.FONT_HERSHEY_SIMPLEX
-                    font_scale = 1
-                    thickness = 2
-                    color = (0, 255, 0)
-                    text =f"""
-                    ID: {session_id}
-                    FPS: {session.measured_fps:.0f}
-                    CPU: {session.cpu_usage:02.0f}%
-                    """
-
-                    y0, dy = 30, 36
-                    for i, line in enumerate(text.split('\n')):
-                        (text_width, text_height), _ = cv2.getTextSize(line, font, font_scale, thickness)
-                        x = frame.shape[1] - text_width - 10
-                        y = y0 + (i - 1) * dy
-                        cv2.putText(frame, line, (x, y), font, font_scale, color, thickness, cv2.LINE_AA)
-
             # control framerate
-            next_frame_time += frame_duration
-            sleep_time = next_frame_time - time.time()
-            if sleep_time > 0:
-                time.sleep(sleep_time)
-            else:
-                next_frame_time = time.time()
-
-            session.latest_frame = frame
+            if time.time() >= next_frame_time:
+                ret, frame = cap.read()
+
+                # measure FPS
+                frame_count += 1
+                now = time.time()
+                if now - last_time >= rolling_duration:  
+                    session.measured_fps = frame_count / (now - last_time)
+                    session.cpu_usage = psutil.cpu_percent(interval=None)
+                    frame_count = 0
+                    last_time = now
+
+                if not ret:
+                    cap.set(cv2.CAP_PROP_POS_FRAMES, 0)
+                    continue
+                else:
+                    if session.show_stats:
+                        font = cv2.FONT_HERSHEY_SIMPLEX
+                        font_scale = 1
+                        thickness = 2
+                        color = (0, 255, 0)
+                        text =f"""
+                        ID: {session_id}
+                        FPS: {session.measured_fps:.0f}
+                        CPU: {session.cpu_usage:02.0f}%
+                        """
+
+                        y0, dy = 30, 36
+                        for i, line in enumerate(text.split('\n')):
+                            (text_width, text_height), _ = cv2.getTextSize(line, font, font_scale, thickness)
+                            x = frame.shape[1] - text_width - 10
+                            y = y0 + (i - 1) * dy
+                            cv2.putText(frame, line, (x, y), font, font_scale, color, thickness, cv2.LINE_AA)
+                session.latest_frame = frame
+
+                next_frame_time += frame_duration
 
 def stream_mjpeg(session_id: str):
     global sessions