尝试修复画面延迟问题

hls_service_ws_kadian.py

@@ -331,7 +331,7 @@ class HLSKadianService:
 
         self.stop_event = threading.Event()
         self.raw_queue = queue.Queue(maxsize=3)     # 原始队列，容量较小
-        self.ws_queue = queue.Queue(maxsize=1000)   # WebSocket队列
+        self.ws_queue = queue.Queue(maxsize=10)     # WebSocket队列，减小容量防止延迟累积
 
         self.frame_processor_workers = []
         self.biz_processor = get_processor(self.algorithm)(self.raw_queue, self.ws_queue, self.stop_event, self.cameras)

utils/web_socket_sender.py

@@ -1,4 +1,5 @@
 
+
 import json
 import asyncio
 import websockets
@@ -26,18 +27,71 @@ class WebSocketSender(threading.Thread):
         finally:
             self.ws_clients.discard(websocket)
 
+    def _get_latest_msg(self):
+        """
+        从队列获取最新消息，丢弃旧消息
+        返回: (最新消息, 丢弃数量)
+        """
+        msg = None
+        dropped = 0
+        try:
+            # 获取第一条消息
+            msg = self.send_queue.get_nowait()
+            dropped = 0
+            
+            # 尝试获取更新的消息，丢弃旧的
+            while True:
+                try:
+                    msg = self.send_queue.get_nowait()
+                    dropped += 1
+                except queue.Empty:
+                    break
+                    
+            if dropped > 0:
+                self.send_queue.task_done()  # 为第一条标记完成
+        except queue.Empty:
+            pass
+            
+        return msg, dropped
+
     async def _broadcaster(self):
         while not self.stop_event.is_set():
             try:
-                msg = await asyncio.to_thread(self.send_queue.get, timeout=0.5)
+                # 使用短超时获取消息
+                msg = await asyncio.to_thread(self.send_queue.get, timeout=0.1)
             except queue.Empty:
+                # 尝试获取最新消息（丢弃队列中的旧消息）
+                msg, dropped = await asyncio.to_thread(self._get_latest_msg)
+                if msg is None:
+                    continue
+                if dropped > 0:
+                    logger.debug(f"[DEBUG] Dropped {dropped} old frames to catch up")
+            
+            # 尝试丢弃更多旧消息，只保留最新
+            dropped = 0
+            while True:
+                try:
+                    msg = self.send_queue.get_nowait()
+                    dropped += 1
+                except queue.Empty:
+                    break
+            if dropped > 0:
+                logger.debug(f"[DEBUG] Dropped {dropped} queued frames, sending latest")
+            
+            # 在线程池中执行JSON序列化，避免阻塞事件循环
+            try:
+                data = await asyncio.to_thread(json.dumps, msg)
+            except Exception as e:
+                logger.error(f"[ERROR] JSON serialization failed: {e}")
+                self.send_queue.task_done()
                 continue
-            data = json.dumps(msg)
+                
             dead = []
             for ws in list(self.ws_clients):
                 try:
                     await ws.send(data)
-                except:
+                except Exception as e:
+                    logger.debug(f"[DEBUG] WebSocket send error: {e}")
                     dead.append(ws)
             for ws in dead:
                 self.ws_clients.discard(ws)