python - 为什么 Flask 应用程序没有第二次运行？

问题描述

我在视频上创建了一个对象检测的 Flask 应用程序。在这个应用程序中，我从用户那里获取视频输入。该视频由我们的应用程序处理，在屏幕上显示检测并在完成该过程后下载视频。但是，当我在同一个应用程序上通过同一个会话传递同一个视频或另一个视频时，它就不起作用了。它没有向我显示任何错误。在这里，我附上了我的项目的示例代码。

完成此应用程序中第一个视频的流程后，如何传递另一个视频？

from flask import Flask, render_template, request,  flash, redirect, url_for, send_from_directory
from werkzeug.utils import secure_filename
from PIL import Image
from os import listdir
import numpy as np
import pandas as pd
import cv2
import os
import matplotlib.pyplot as plt
import re
from pathlib import Path
app = Flask(__name__)
UPLOAD_FOLDER = os.path.dirname(os.path.abspath(__file__)) + '/uploads/'
DOWNLOAD_FOLDER = os.path.dirname(os.path.abspath(__file__)) + '/downloads/'
DIR_PATH = os.path.dirname(os.path.realpath(__file__))
app.config['UPLOAD_FOLDER'] = UPLOAD_FOLDER
app.config['DOWNLOAD_FOLDER'] = DOWNLOAD_FOLDER
ALLOWED_EXTENSIONS = {'mp4'}
app.secret_key = 'random string'
def allowed_file(filename):
    return '.' in filename and filename.rsplit('.', 1)[1].lower() in ALLOWED_EXTENSIONS
def my_func(filename):
    name = filename.split('/')[-1].split(".")[0]
    cap= cv2.VideoCapture(filename)
    i=0
    images = []
    while(cap.isOpened()):
        ret, frame = cap.read()
        if not ret: break
        font = cv2.FONT_HERSHEY_SIMPLEX
        org = (5,20)
        fontScale = 0.5
        color = (0, 0, 255)
        fontstroke = 2
        image1 = cv2.putText(frame, 'Done', org, font, fontScale, color, fontstroke)
        images.append(image1)
        i+=1
    height, width, channels = images[0].shape
    fourcc = cv2.VideoWriter_fourcc(*'mp4v')
    out = cv2.VideoWriter('downloads/' + name + '.mp4', fourcc, 20, (width, height))
    for pic in images:
        out.write(pic)
        cv2.imshow('video',pic)
        if (cv2.waitKey(150) & 0xFF) == ord('q'): # Hit `q` to exit
            break
    out.release()
    cv2.destroyAllWindows()
@app.route('/', methods=['POST', 'GET'])
def index():
    if request.method == 'POST':
        if 'file' not in request.files:
           print('No file attached in request')
           return redirect(request.url)
        file = request.files['file']
        if file.filename == '':
            print('No file selected')
            return redirect(request.url)
        if file and allowed_file(file.filename):
            filename = secure_filename(file.filename)
            file.save(os.path.join(app.config['UPLOAD_FOLDER'], filename))
            my_func(os.path.join(app.config['UPLOAD_FOLDER'], filename))
            os.remove(os.path.join(app.config['UPLOAD_FOLDER'], filename))
            return redirect(url_for('uploaded_file', filename=filename))
    return render_template('index.html')
@app.route('/downloaded/<filename>', methods=['POST', 'GET'])
def uploaded_file(filename):
    return send_from_directory(app.config['DOWNLOAD_FOLDER'], filename, as_attachment=True)
if __name__ == '__main__':
    app.run(debug = True)

这里我提到 index.html 文件的代码。

<!DOCTYPE html>
<html lang="en">

    <head>
        <meta charset="UTF-8">
        <title>Model</title>
    </head>
    <body>
    <div align="center">
        <h1>Recognition</h1>
        <h2>Upload Video</h2>
        <form method="post" enctype=multipart/form-data>
            <p><input type=file name=file value="REFRESH">
                <input type=submit value=Upload></p>

        </form>
    </div>
    </body>
    </html>

标签： pythonflask

python - 为什么 Flask 应用程序没有第二次运行？

问题描述

解决方案

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