Python中的多線程cv2.imshow（）不起作用

我有兩個攝像頭（使用OpenNI，每個攝像頭有兩個流，由相同的驅動程序API實例處理），並且想要兩個線程，每個線程捕獲數據從每個攝像機獨立，即驅動程序API的一個實例，說cam_handler，我有兩個流depth和rgb每臺攝像機，說cam_handler.RGB1_stream和cam_handler.DEPTH1_streamPython中的多線程cv2.imshow（）不起作用

下面是相同的代碼：

import threading 

def capture_and_save(cam_handle, cam_id, dir_to_write, log_writer, rgb_stream, 
        depth_stream, io): 
    t = threading.currentThread() 
    shot_idx = 0 
    rgb_window = 'RGB' + str(cam_id) 
    depth_window = 'DEPTH' + str(cam_id) 
    while getattr(t, "do_run", True): 
     if rgb_stream is not None: 

      rgb_array = cam_handle.get_rgb(rgb_stream) 
      rgb_array_disp = cv2.cvtColor(rgb_array, cv2.COLOR_BGR2RGB) 
      cv2.imshow(rgb_window, rgb_array_disp) 
      cam_handle.save_frame('rgb', rgb_array, shot_idx, dir_to_write + str(cam_id + 1)) 
      io.write_log(log_writer[cam_id], shot_idx, None) 

     if depth_stream is not None: 
      depth_array = cam_handle.get_depth(depth_stream) 
      depth_array_disp = ((depth_array/10000.) * 255).astype(np.uint8) 
      cv2.imshow(depth_window, np.uint8(depth_array_disp)) 
      cam_handle.save_frame('depth', depth_array, shot_idx, dir_to_write + str(cam_id + 1)) 
     shot_idx = shot_idx + 1 

     key = cv2.waitKey(1) 
     if key == 27: # exit on ESC 
      break 
    print "Stopping camera %d thread..." % (cam_id + 1) 
    return 

def main(): 
    ''' Setup camera threads ''' 
    cam_threads = [] 
    dir_to_write = "some/save/path" 
    for cam in range(cam_count): 
     cam = (cam + 1) % cam_count 
     cv2.namedWindow('RGB' + str(cam)) 
     cv2.namedWindow('DEPTH' + str(cam)) 
     one_thread = threading.Thread(target=capture_and_save, 
             name="CamThread" + str(cam + 1), 
             args=(cam_cap, cam, dir_to_write, 
              log_writer, 
              rgb_stream[cam], depth_stream[cam], io,)) 
     cam_threads.append(one_thread) 
     one_thread.daemon = True 
     one_thread.start() 

     try: 
      while True: 
       pass 
       # cv2.waitKey(1) 
     except KeyboardInterrupt: 
      ''' Stop everything ''' 
      for each_thread in cam_threads: 
       each_thread.do_run = False 
       each_thread.join(1) 
      cam_cap.stop_rgb(rgb_stream) 
      cam_cap.stop_depth(depth_stream) 

      ''' Stop and quit ''' 
      openni2.unload() 
      cv2.destroyAllWindows() 

if __name__ == '__main__': 
    main()

所以，我的問題是，如果我刪除cv2.imshow()代碼中的所有行都按預期運行，我將兩個攝像頭輸出保存到文件。但是，使用cv2.imshow()行時，只會創建「空白」窗口，並且線程似乎「卡住」，根本沒有輸出。
我嘗試了幾個建議，包括將namedWindow創建移動到主線程以及capture_and_save線程。我也嘗試在waitKey()之間移動，因爲據說OpenCV只允許在主線程中使用waitKey()。然而，沒有區別。

來源

2017-06-15 Kanishka Ganguly