Python 中的网络摄像头运动检测程序 ?


在这项中,我们准备编写一个 Python 程序,它将分析从网络摄像头获取的图像,尝试检测运动并以 CSV 文件的形式存储网络摄像头视频的时间间隔。

所需库

我们将使用 OpenCV 和 pandas 库。如果尚未安装,可以使用 pip 安装它,如下所示

$pip install opencv2, pandas

代码示例

#Import required libraries
import cv2
import pandas as pd
import time
from datetime import datetime

#Initialise variables
stillImage = None
motionImage = [ None, None ]
time = []

# Initializing the DataFrame with start and end time
df = pd.DataFrame(columns = ["start", "end"])

# Capturing video
video = cv2.VideoCapture(0)

while True:
   # Start reading image from video
   check, frame = video.read()
   motion = 0

   # Convert color image to gray_scale image
   gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
   gray = cv2.GaussianBlur(gray, (21, 21), 0)
   if stillImage is None:
      stillImage = gray
      continue
   # Still Image and current image.
   diff_frame = cv2.absdiff(stillImage, gray)

   # change the image to white if static background and current frame is greater than 25.
   thresh_frame = cv2.threshold(diff_frame, 25, 255, cv2.THRESH_BINARY)[1]
   thresh_frame = cv2.dilate(thresh_frame, None, iterations = 2)
   # Finding contour and hierarchy from a moving object.
   contours,hierachy = cv2.findContours(thresh_frame.copy(),
      cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)
   for contour in contours:
      if cv2.contourArea(contour) < 10000:
         continue
      motion = 1
      (x, y, w, h) = cv2.boundingRect(contour)
      cv2.rectangle(frame, (x, y), (x + w, y + h), (0, 255, 0), 3)
   # Append current status of motion
   motionImage.append(motion)
   motionImage = motionImage[-2:]
   # Append Start time of motion
   if motionImage[-1] == 1 and motionImage[-2] == 0:
      time.append(datetime.now())

   # Append End time of motion
   if motionImage[-1] == 0 and motionImage[-2] == 1:
      time.append(datetime.now())
   # Displaying image in gray_scale
   cv2.imshow("Gray_Frame", gray)

   # Display black and white frame & if the intensity difference is > 25, it turns white
   cv2.imshow("Threshold Frame", thresh_frame)
   # Display colored frame
   cv2.imshow("Colored_Frame", frame)

   key = cv2.waitKey(1)
   # Press q to stop the process
   if key == ord('q'):
      if motion == 1:
         time.append(datetime.now())
      break

# Append time of motion
for i in range(0, len(time), 2):
   df = df.append({"Start":time[i], "End":time[i + 1]}, ignore_index = True)

# Creating a csv file in which time of movements will be saved
df.to_csv("FrameInMotion_time.csv")

video.release()

# close window
cv2.destroyAllWindows()

输出

我们可以看到,我们将获得 3 个不同的窗口,它们将以 3 种不同的模式(灰度、彩色和黑白)显示我们网络摄像头的当前运动。

它还将在 CSV 文件中存储网络摄像头运动的时间,而且 CSV 的输出类似于

FrameMotion_time.csv(输出)

start     end      End                            Start
0                  2019-02-21 18:10:59.718005     2019-02-21 18:08:35.791487

更新于: 2019 年 7 月 30 日

290 次浏览

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