Python OpenCV Calling Camera and Screenshot Saving Function Implementation Code

0x01 OpenCV Installation

By command pip install opencv-python Installation

pip install opencv-python

Example 0x02

import cv2
cap = cv2.VideoCapture(0)    # Turn on the camera 
while(1):
  # get a frame
  ret, frame = cap.read()
  # show a frame
  cv2.imshow("capture", frame)   # Generate camera window 
  if cv2.waitKey(1) & 0xFF == ord('q'):  # If you press q  Save and exit the screenshot 
    cv2.imwrite("D:/test.png", frame)  # Save path 
    break
cap.release()
cv2.destroyAllWindows()

ps: Let's take a look at python calling the microphone; Camera; Screen capture;

# -*- coding: utf-8 -*-
"""
Created on Mon Jun 24 14:47:35 2019
@author: erio
"""
from PIL import Image,ImageGrab
import cv2
import pyaudio
import wave
'''
#录音
input_filename = "record.wav"             # 麦克风采集的语音输入
input_filepath = "E:"       # 输入文件的path
in_pathrec = input_filepath + input_filename     #通俗解释就是wav文件路径
def get_audio(filepath):
    CHUNK = 256         #定义数据流块
    FORMAT = pyaudio.paInt16  #量化位数（音量级划分）
    CHANNELS = 1        # 声道数;声道数：可以是单声道或者是双声道
    RATE = 8000        # 采样率;采样率：1秒内对声音信号的采集次数，常用的有8kHz, 16kHz, 32kHz, 48kHz, 11.025kHz, 22.05kHz, 44.1kHz
    RECORD_SECONDS = 10     #录音秒数
    WAVE_OUTPUT_FILENAME = filepath   #wav文件路径
    p = pyaudio.PyAudio()        #实例化
    stream = p.open(format=FORMAT,
            channels=CHANNELS,
            rate=RATE,
            input=True,
            frames_per_buffer=CHUNK)
    # print("*"*10, "开始录音：请在5秒内输入语音")
    frames = []                         #定义1个列表
    for i in range(0, int(RATE / CHUNK * RECORD_SECONDS)):   #循环，采样率11025 / 256 * 5
      data = stream.read(CHUNK)                #读取chunk个字节 保存到data中
      frames.append(data)                   #向列表frames中添加数据data
   # print(frames)
   # print("*" * 10, "录音结束\n")
    stream.stop_stream()
    stream.close()     #关闭
    p.terminate()      #终结
    wf = wave.open(WAVE_OUTPUT_FILENAME, 'wb')         #打开wav文件创建1个音频对象wf，开始写WAV文件
    wf.setnchannels(CHANNELS)                  #配置声道数
    wf.setsampwidth(p.get_sample_size(FORMAT))         #配置量化位数
    wf.setframerate(RATE)                    #配置采样率
    wf.writeframes(b''.join(frames))              #转换为2进制数据写入文件
    wf.close()       #关闭
get_audio(in_pathrec)
'''
#截屏
input_filenamescr = "screen.jpg"             
input_filepath = "E:"     
in_pathscr = input_filepath + input_filenamescr   
def get_screen(filepath):
  img = ImageGrab.grab()
  img.save(filepath)
get_screen(in_pathscr)
'''
#拍照
input_filenamecam = "camera.jpg"             
input_filepath = "E:"     
in_pathcam = input_filepath + input_filenamecam  
def get_camera(filepath):
  cap=cv2.VideoCapture(0)
  ret,frame = cap.read()
  i=0;
  cv2.imwrite(filepath,frame)
  cap.release()
  cv2.destroyAllWindows()
get_camera(in_pathcam)
'''
'''
#录制视频
cap = cv2.VideoCapture(0)#创建1个 VideoCapture 对象
flag = 1 #设置1个标志，用来输出视频信息
num = 1 #递增，用来保存文件名
while(cap.isOpened()):#循环读取每1帧
  ret_flag, Vshow = cap.read() #返回两个参数，第1个是bool是否正常打开，第2个是照片数组，如果只设置1个则变成1个tumple包含bool和图片
  cv2.imshow("Capture_Test",Vshow) #窗口显示，显示名为 Capture_Test
  k = cv2.waitKey(1) & 0xFF #每帧数据延时 1ms，延时不能为 0，否则读取的结果会是静态帧
  if k == ord('s'): #若检测到按键 ‘s'，打印字符串
    cv2.imwrite("D:/pycharmthings/IMF/getpics/"+ str(num) + ".jpg", Vshow)
    print(cap.get(3)); #得到长宽
    print(cap.get(4));
    print("success to save"+str(num)+".jpg")
    print("-------------------------")
    num += 1
  elif k == ord('q'): #若检测到按键 ‘q'，退出
    break
cap.release() #释放摄像头
cv2.destroyAllWindows()#删除建立的全部窗口
'''

Summarize