总结两种使用OpenCv连接海康相机播放视频画面方法（demo）

情况一：项目和相机在同一网段

  创建.py文件命名为：Config,构造一个通过数据库查询相机的ip,username, password 的类，方便连取相机时获取相机的ip,username, password问题。

Config.py具体如下所示：

import pymysql


class BaseSet():
    # 连接数据库基础参数
    def __init__(self):
        # 连接数据库
        self.conn = pymysql.connect(host='localhost'  # 连接名称，默认127.0.0.1
                                    , user='root'  ## 用户名
                                    , passwd='root'  # 密码
                                    , port=3306  # 端口，默认为3306
                                    , db='camera'  # 数据库名称
                                    , charset='utf8'  # 字符编码
                                    )
        self.cur = self.conn.cursor()  # 生成游标对象

        # Sql语句
        self.ConstructionSql = 'SELECT ip,username, password FROM cameras'

    def GetCamIDInfo(self):
        try:
            self.cur.execute(self.ConstructionSql)  # 执行插入的sql语句
            return self.cur.fetchall()
        except:
            self.conn.commit()  # 提交到数据库执

  创建.py文件命名为demo,这里将是你链接相机播放视频画面的核心部分了，这里我们将涉及多进程读取相机播放视频画面.

import multiprocessing
from Config import BaseSet
import cv2


def GetInfolIST():
    Config = BaseSet()
    IpList = []
    UsernameList = []
    PasswordList = []
    for ip, username, password in Config.GetCamIDInfo():
        IpList.append(ip)
        UsernameList.append(username)
        PasswordList.append(password)
    return IpList, UsernameList, PasswordList


def SaveFrams(username, password, ip):
    rtsp = "rtsp://%s:%s@%s:554/cam/realmonitor?channel=1&subtype=1" % (username, password, ip)
    cap = cv2.VideoCapture(rtsp)
    if cap.isOpened():
        ret, frame = cap.read()  # read_latest_frame() 替代 read()
        if ret:
            print("Can receive frame. Starting ..")
            cv2.imshow("video-%s" %ip, frame)
        else:
            cap.release()


if __name__ == '__main__':
    IpList, UsernameList, PasswordList = GetInfolIST()
    while True:
        p = multiprocessing.Pool(5)
        r_list = []
        for username, password, ip in zip(UsernameList, PasswordList, IpList):
            r_list.append(p.apply_async(SaveFrams, args=(username, password, ip)))
        p.close()
        for r in r_list:
            r.get()

情况二：项目和相机不在同一网段

这里我们沿用情况一中获取ip,username, password结果，更改为获取相机indexcode。这里文件命名为： ConfigMysql.py 代码部分如下：

import pymysql


class BaseSetMySql():
    # 连接数据库基础参数
    def __init__(self):
        # 连接数据库
        self.conn = pymysql.connect(host='localhost'  # 连接名称，默认127.0.0.1
                                    , user='root'  ## 用户名
                                    , passwd='root'  # 密码
                                    , port=3306  # 端口，默认为3306
                                    , db='CamIndexcode'  # 数据库名称
                                    , charset='utf8'  # 字符编码
                                    )
        self.cur = self.conn.cursor()  # 生成游标对象

        # Sql语句

        self.Sql = 'SELECT indexcode FROM indexcodes'


    # 获取摄像机编码
    def GetCamID(self):
        try:
            self.cur.execute(self.Sql)  # 执行插入的sql语句
            CamID = self.cur.fetchall()
            return CamID
        except:
            self.conn.commit()  # 提交到数据库执

创建ConfigRTSP.py文件用来通过indexcode发送请求获取RTSP

import requests


class BaseSetRTSP():
    def __init__(self):

        self.UrlIndexCode = 'http://localhost:8090/Hikvision/previewURLs'

    # 获取RTSP
    def GetRTSP(self, CamId):
        data = {'cameraIndexCode': CamId}
        RestData = requests.post(self.UrlIndexCode, data=data)
        RestDataDict = RestData.json()
        RTSP = None
        RightInfo = "rtsp" in str(RestDataDict)
        if RightInfo is True:
            Data_RestDataDict = ((eval(RestDataDict['data']))['data'])
            RTSP = Data_RestDataDict['url']
        return RTSP

创建ConfigFrame.py用来播放视频画面，代码如下：

import uuid
import cv2
import os
os.environ["OPENCV_FFMPEG_CAPTURE_OPTIONS"] = "rtsp_transport;udp"

class BaseSetSaveFrame():
    def __init__(self):
        pass

    # 
    def PlayFrame(self, CAMID, RTSP):
    cap = cv2.VideoCapture(rtsp)
    if cap.isOpened():
        ret, frame = cap.read()  # read_latest_frame() 替代 read()
        if ret:
            print("Can receive frame. Starting ..")
            cv2.imshow("video-%s" %CAMID, frame)
        else:
            cap.release()

**接下来就是调用上面的类进行获取相机画面了，在此之前需要将上述的三个文件放置在一个名为ImagesConfig的文件夹中。调用代码如下：

import multiprocessing
from ImagesConfig.ConfigMysql import BaseSetMySql
from ImagesConfig.ConfigRTSP import BaseSetRTSP
from ImagesConfig.ConfigSaveFrame import BaseSetSaveFrame



# 整体流程：播放裸土图像
def PlayCamsImgs():

    ConfigMysql = BaseSetMySql()
    ConfigRTSP = BaseSetRTSP()
    AllCamId = ConfigMysql.GetCamID()
    for CamIdName in AllCamId:
        ListCamIds = list(CamIdName)
        CamId = ' '.join(str(i) for i in ListCamIds)
        RTSP = ConfigRTSP.GetRTSPCamId)
        if RTSP is not None:
            print("正在连接此RTSP:", RTSP)
            ConfigSaveFrame = BaseSetSaveFrame()
            ConfigSaveFrame.PlayFrame(CamId, RTSP)


if __name__ == '__main__':
    PlayCamsImgs()