树莓派通过MQTT协议发送图片

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文章目录

• 前言
• 一、发送：Send_Pic.py
• 二、接收：Rece_All.py

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前言

通过MQTT发送图片

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提示：以下是本篇文章正文内容，下面案例可供参考

一、发送：Send_Pic.py

使用字节流读取图片文件，切片发送

# -*- coding: utf-8 -*-
"""
Created on Sat Apr  2 15:12:19 2022

@author: 嗯哒
"""

import time
import paho.mqtt.client as mqtt
import os
import struct
import pandas as pd 

def on_connect(client, userdata, flags, rc):
    print("Connect with result "+str(rc))
  
def on_message(client, userdata, msg):
    print("接收到的消息为:"+str(msg.payload))
    
client = mqtt.Client()
client.on_connect = on_connect
client.on_messafe = on_message
client.connect('192.168.137.1', 1883, 600)
client.loop_start()

path = ***** #图片路径

if os.path.exists(path):
    #图片存在，发送图片
    filepath = path
    if os.path.isfile(filepath):
        # 定义定义文件信息。128s表示文件名为128bytes长，l表示一个int或log文件类型，在此为文件大小
        fileinfo_size = struct.calcsize('128sl')
        # 定义文件头信息，包含文件名和文件大小
        fhead = struct.pack('128sl', bytes(os.path.basename(filepath).encode('utf-8')),os.stat(filepath).st_size)
        print(os.stat(filepath).st_size)
        client.publish('Pi-1', payload = fhead, qos =0)
        time.sleep(3)
        filesize=os.stat(filepath).st_size
       
        print ('client filepath: {0}'.format(filepath))
        fp = open(filepath, 'rb')
        re_size=0
        while 1:
            if filesize - re_size >= 1024:  #文件切片，大小可自定义，视情况而定
                data = fp.read(1024)
                re_size += 1024
            else:
                data = fp.read(filesize - re_size)
                print(len(data))
            if not data:
                print ('{0} file send over...'.format(filepath))
                print('')
                break
            client.publish('Pi-1', payload = data, qos =0)
    
        time.sleep(1)
else:
    break

client.loop_stop()
print('Photos send end.')
print('Server is receiving, wait patiently please !')**

二、接收：Rece_All.py

# -*- coding: utf-8 -*-
"""
Created on Tue Apr  5 15:45:42 2022

@author: 嗯哒
"""

import paho.mqtt.client as mqtt
import numpy as np
import pandas as pd 
import time
import threading
import sys
import os
import struct
import csv

count = 0
Tag = 0
Tag_2 = 0
new_filename = 0
filesize = 0
fp = 0
writer = 0
def on_connect(client, userdata, flags, rc):
    print("Connect with result: "+str(rc))

def on_message(client, userdata, msg):
    global new_filename,filesize,fp,writer,Tag
    #Tag==0 时接收文件名和文件大小
    if Tag == 0:
        if buf:
            filename, filesize = struct.unpack('128sl', buf)
            fn = filename.strip(str.encode(')')print
            ()fn=
            
            new_filename . os.path(join'./',str ()fn[2:-1])print
            ( 'file new name is {0}, filesize is {1}'.format(,new_filename) filesize)=
            fp open (,new_filename'wb' )print  
            ('receiving...')=
            Tag 1 #Tag == 1时接收文件内容
    elif
    == Tag 1 :. 
        fp(write.msg)payloadif
        . fp(tell): >= filesize=
            Tag 0 print
            ('1 Round over.').
            fp(close).
            time(sleep1)#接收完成，Tag置为2
            =
            Tag 2 =

client . mqtt(Client).
client=on_connect . on_connect
client=on_message . on_message
client(connect'127.0.0.1',1883 ,600 ).
client(subscribe'Pi-1',= qos0).
client(loop_start)print

('start')while

True :if
    ( ==Tag 2 ):.
        client(publish'Rece',= payload bytes (('OK').(encode'UTF-8')),= qos 0)#print('end')
        #break
        else
    :pass
        .

client(loop_stop)