循环刷新实时图片，点击后会未响应，求大神帮忙！

from VideoCapture import *
from vtk import *
import time
import os
global i
global reader
global viewer
global iren
i=1
picker = vtk.vtkCellPicker()
def abc(object, event):
global i
global reader
global viewer
global iren
while (1):
print i
cam.saveSnapshot('test%d.jpg'%i, timestamp=3, boldfont=1, quality=100)
reader.SetFileName("C:\\Users\\szk\\Desktop\\test%d.jpg"%i)
#viewer = vtkImageViewer2()
viewer.SetInputConnection(reader.GetOutputPort())
viewer.Render()
viewer.SetupInteractor(iren)
os.remove("C:\\Users\\szk\\Desktop\\test%d.jpg"%i)
i=i+1
#devnum=0是摄像头，1是采集卡
cam = Device(devnum=0, showVideoWindow=0)
cam.saveSnapshot('test%d.jpg'%i, timestamp=3, boldfont=1, quality=100)
reader = vtkJPEGReader()
reader.SetFileName("C:\\Users\\szk\\Desktop\\test%d.jpg"%i)
viewer = vtkImageViewer2()
viewer.SetInputConnection(reader.GetOutputPort())
viewer.Render()
iren = vtkRenderWindowInteractor()
viewer.SetupInteractor(iren)
iren.AddObserver ("LeftButtonPressEvent",abc)
iren.SetPicker (picker)
iren.Initialize()
iren.Start()

点击后一直在while(1)这里循环？