CV2 在一段时间后开始拍摄 emty 图像

Question

我是Python的新手，我有一个小问题。我应该在很长一段时间内用网络摄像头每 10 秒拍摄一次图像。我的代码工作了大约 5 小时或 1800 张图片，然后突然之间我保存的图片是 emty。我不知道是什么导致了错误，也没有收到错误消息，skript 一直在运行。

我正在使用 spyder 和 python 2.7。当我重新启动内核时，我的 skript 再次工作了几个小时。这是我的代码：

import cv2
import time
import datetime
import os
data_path = 'V:\Database\Pictures'
try:
  while True:
       cam = cv2.VideoCapture(0)
       cam.set(3,1280) #set height
       cam.set(4,720) #set width
       s, im = cam.read() # captures image
    # Write date and time to image
       date_string = time.strftime("%Y-%m-%d %H:%M:%S")
       font                   = cv2.FONT_HERSHEY_SIMPLEX
       bottomLeftCornerOfText = (10,710)
       fontScale              = 1
       fontColor              = (255,255,255)
       lineType               = 2
       cv2.putText(im,date_string, 
           bottomLeftCornerOfText, 
           font, 
           fontScale,
           fontColor,
           lineType)

       temp = datetime.datetime.fromtimestamp(time.time())
       year = temp.year           
       month = temp.month
       day = temp.day
       hour = temp.hour
       minute = temp.minute
       second = temp.second
       imagename = year+'-'+month+'-'+day+'_'+hour+'-'+minute+'-   '+second+'.jpg'
         # writes image  to disk    
       cv2.imwrite(os.path.join(data_path,imagename),im)    
       cam.release()
       time.sleep(10)
finally:
  cam.release()

这是我的记忆力有问题吗？一张图片的大小为 261KB。

Answer 1

硬盘已满？不确定这是否可以解决问题，但您应该重新排列代码。无需每次都重新初始化相机：

import cv2
import time
import datetime
import os
data_path = 'V:\Database\Pictures'
cam = cv2.VideoCapture(0)
cam.set(3,1280) #set height
cam.set(4,720) #set width
font                   = cv2.FONT_HERSHEY_SIMPLEX
bottomLeftCornerOfText = (10,710)
fontScale              = 1
fontColor              = (255,255,255)
lineType               = 2
while True:
    try:
        s, im = cam.read() # captures image
    except:
        # something here
        pass
    now = datetime.datetime.now()
    date_string = now.strftime("%Y-%m-%d %H:%M:%S")
    cv2.putText(im,date_string, 
        bottomLeftCornerOfText, 
        font, 
        fontScale,
        fontColor,
        lineType)
    imagename = now.strftime("%Y-%m-%d_%H-%M-%S") + '.jpg'
    # writes image  to disk    
    cv2.imwrite(os.path.join(data_path,imagename),im)    
    time.sleep(10)
cam.release()