Question

我有一个基于Python和Flask的简单Web应用程序，带有三个HTML按钮。

<!DOCTYPE html>
<html>
    <head>
        <title>Raspberry Pi OpenCV Webstream</title>
        <!--<link rel = "stylesheet" href = "{{ url_for('static', filename='css/main.css') }}">-->
    </head>
    <body>
        <header>
            <h1 class = "Title">Raspberry Pi OpenCV Webstream</h1>
        </header>
        <main>
            <table width = "100%" border = "0">
                <tr>
                    <td>
                        <img height = "800" width = "800" src = "{{ url_for('VideoFrame') }}">
                    </td>
                </tr>
                <tr>
                    <td>
                        <form method = "post" action = "/">
                            <button class = "ActionButton" type = "submit" name = "action_start" value = "1">Start</button>
                            <button class = "ActionButton" type = "submit" name = "action_pause" value = "1">Pause</button>
                            <button class = "ActionButton" type = "submit" name = "action_stop" value = "1">Stop</button>
                        </form>
                    </td>
                </tr>
            </table>
        </main>
    </body>
</html>

还有我的Python应用程序

app.py

from OpenCVWebstream import OpenCVWebstream

IsActive = True

def onStop():
    global IsActive

    IsActive = False

if(__name__ == "__main__"):
    app = OpenCVWebstream(onStop = onStop)
    app.Run()

    while(IsActive):
        pass

    print("[INFO] Exit application...")

    exit(0)

OpenCVWebStream.py

import cv2
import time

from threading import Thread
from multiprocessing import Process
from flask import Flask
from flask import Response
from flask import render_template
from flask import request

class OpenCVWebstream():
    def __init__(self, CameraID = 0, onStop = None):
        self.__app = Flask(__name__)

        # On stop handler
        self.__onStop = onStop

        # Open the camera
        #self.__Camera = cv2.VideoCapture(CameraID)

        # Current image
        self.__CurrentFrame = None

        self.__CaptureWorker = None

        self.__VideoActive = False
        self.__VideoPaused = False

        # Register endpoints
        self.__app.add_url_rule(rule = "/", endpoint = "index", view_func = self.__showIndex, methods = ["GET", "POST"])
        self.__app.add_url_rule(rule = "/VideoFrame", endpoint = "VideoFrame", view_func = self.__getVideoFrame)

        self.__Server = Thread(target = self.__flaskThread)
        self.__Server.setDaemon(True)

    def __getFrame(self):
        while True:
            if(self.__CurrentFrame is None):
                continue

            yield(b'--frame\r\n'
                    b'Content-Type: image/jpeg\r\n\r\n'+ self.__CurrentFrame + b'\r\n')

            # This time is neccessary when you use Firefox
            time.sleep(0.01)

    def __flaskThread(self):
        self.__app.run(host = "0.0.0.0", port = 80)

    def __captureThread(self):
        while(True):
            if(not(self.__VideoPaused)):
                #ret, self.__CurrentFrame = self.__Camera.read()
                pass

            if(not(self.__VideoActive)):
                break

    """
    Endpoints
    """
    def __showIndex(self):
        if(request.method == "POST"): 
            if(request.form.get("action_start") == "1"):
                self.StartCapture()
            elif(request.form.get("action_pause") == "1"):
                self.PauseCapture()
            elif(request.form.get("action_stop") == "1"):
                self.Stop()

        return render_template("index.html")

    def __getVideoFrame(self):
        return Response(self.__getFrame(), mimetype = "multipart/x-mixed-replace; boundary=frame")

    """
    Public methods
    """
    def StartCapture(self):
        self.__VideoActive = True
        self.__VideoPaused = False
        self.__CaptureWorker = Thread(target = self.__captureThread)
        self.__CaptureWorker.daemon = True
        self.__CaptureWorker.start()

        print("[DEBUG - {}] Capture started!".format(time.strftime("%H:%M:%S")))

    def PauseCapture(self):
        self.__VideoPaused = True

        print("[DEBUG - {}] Capture paused!".format(time.strftime("%H:%M:%S")))

    def StopCapture(self):
        self.__VideoActive = False
        if(self.__CaptureWorker is not None):
            self.__CaptureWorker.join()

        print("[DEBUG - {}] Capture stopped!".format(time.strftime("%H:%M:%S")))

    def Run(self):
        print("[DEBUG - {}] Starting server...".format(time.strftime("%H:%M:%S")))

        # Start the server
        self.__Server.start()

    def Stop(self):
        print("[DEBUG - {}] Shutdown server...".format(time.strftime("%H:%M:%S")))

        # Wait for the capture thread
        self.StopCapture()

        # Release the camera
        self.__Camera.release()

        if(self.__onStop is not None):
            self.__onStop()

我可以在Windows PC上运行此应用程序，并通过Chrome以0.0.0.0:80连接到Web服务器，单击一些按钮，应用程序将接受此操作。

[DEBUG - 17:54:14] Capture started!
127.0.0.1 - - [06/Sep/2019 17:54:14] "POST / HTTP/1.1" 200 -

但是在我的Raspberry Pi上不起作用。我升级了所有软件包和操作系统，在Raspberry Pi上复制了整个代码，然后启动了应用程序

$ python3 app.py

现在，我通过Raspberry Pi IP地址从Chrome（在Windows PC上）建立了新连接，并单击了一些按钮，但是应用程序对任何按钮都没有反应。

那么，为什么应用程序可以在Windows PC上完美运行，并且可以通过本地主机访问Web服务器，而不能在我的Raspberry Pi上运行？

烧瓶-HTML按钮在Raspberry Pi上不起作用

app.py

OpenCVWebStream.py

0 个答案: