python视频捕获循环

Question

I've written a simple script to continuously capture snapshots from my webcam. My only issue is the videocapture module doesn't always grab an image which in turn crashes the program. I think I could solve this by using an infinite loop but I'm not real certain how to go about it. Here's the script:

from VideoCapture import Device
import datetime
def capt():
  a = datetime.datetime.now().strftime("%Y%m%dT%H%M%S%ms")

  b = str(a)
  cam = Device(devnum=0)
  cam.setResolution(1280, 960)

  cam.saveSnapshot('%s.png' % (b))

for i in range(1, 100000):
  capt()

Answer 1

Try to use cam.getImage instead of cam.saveSnapshot . cam.getImage returns PIL image, thus you are able to determine whether any frame has been actually grabbed or not. The folloing code hasnt been tested:

from VideoCapture import Device
import datetime
def capt():
  a = datetime.datetime.now().strftime("%Y%m%dT%H%M%S%ms")

  b = str(a)
  cam = Device(devnum=0)
  cam.setResolution(1280, 960)

  return cam.getImage(), b

while True:
  im, b = capt()
  if im:
    break
im.save('%s.png' % (b), 'JPEG')