• 视频流


    # urls.py
    from app01 import views
    urlpatterns = [
        url(r'^admin/', admin.site.urls),
        url(r'^video/', views.video),
        url(r'^test/', views.test),
    ]
    
    #views.py
    from django.shortcuts import render
    from django.http import StreamingHttpResponse
    
    def hello():
      yield 'Hello,'
      yield 'there!'
    
    def test(request):
      return StreamingHttpResponse(hello()) # 这里面传的是一个可迭代对象
    
    
    import re
    import os
    import mimetypes
    from wsgiref.util import FileWrapper
    from django.http import StreamingHttpResponse
    
    def file_iterator(file_name, chunk_size=8192, offset=0, length=None):
      with open(file_name, "rb") as f:
        f.seek(offset, os.SEEK_SET)
        remaining = length
        while True:
          bytes_length = chunk_size if remaining is None else min(remaining, chunk_size)
          data = f.read(bytes_length)
          if not data:
            break
          if remaining:
            remaining -= len(data)
          yield data
    
    def stream_video(request, path):   # path视频路径
      """将视频文件以流媒体的方式响应"""
      range_header = request.META.get('HTTP_RANGE', '').strip()
      range_re = re.compile(r'bytess*=s*(d+)s*-s*(d*)', re.I)
      range_match = range_re.match(range_header)
      size = os.path.getsize(path)
      content_type, encoding = mimetypes.guess_type(path)  # 根据由url给出的文件名或URL猜测文件的类型。返回值是一个元组(type, encoding)
      content_type = content_type or 'application/octet-stream'
      if range_match:
        first_byte, last_byte = range_match.groups()
        first_byte = int(first_byte) if first_byte else 0
        last_byte = first_byte + 1024 * 1024 * 8    # 8M 每片,响应体最大体积
        if last_byte >= size:
          last_byte = size - 1
        length = last_byte - first_byte + 1
        resp = StreamingHttpResponse(file_iterator(path, offset=first_byte, length=length), status=206, content_type=content_type)
        resp['Content-Length'] = str(length)
        resp['Content-Range'] = 'bytes %s-%s/%s' % (first_byte, last_byte, size)
        # print(111)  通过打印可以看到走的是视频流
      else:
        # 不是以视频流方式的获取时,以生成器方式返回整个文件,节省内存
        resp = StreamingHttpResponse(FileWrapper(open(path, 'rb')), content_type=content_type)
        resp['Content-Length'] = str(size)
        # print(2222)
      resp['Accept-Ranges'] = 'bytes'
      return resp
    
    def video(request):
        return stream_video(request,r'D:deskpythonprojectday111	est_streammedia575ed05ec95db.mp4')
    
    # 当浏览器请求大文件时,浏览器的请求头会有个Range字段,表示请求的起始字节到终止字节,我们就是通过request拿到这个数据,并通过这个数改变响应的字节流
    # 在html页面中的video src地址不应再写静态文件的地址了,要写url地址,即向服务器发请求的地址
    # 也可以使用这种方法传大文件,并且这样支持断点续传
    # 处理视频流的代码后续最好单独写个文件,然后引用
    
    
    # html页面
    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <meta http-equiv="x-ua-compatible" content="IE=edge">
        <meta name="viewport" content="width=device-width, initial-scale=1">
        <title>Title</title>
    </head>
    <body>
    
    <video width="320" height="240" controls>
        <source src="http://127.0.0.1:8000/video/" type="video/mp4">
        您的浏览器不支持Video标签。
    </video>
    </body>
    </html>
    

      

  • 相关阅读:
    Bundle Adjustment
    BFL ekf imu and odom
    RNN
    深度学习的数学(笔记)
    BP 神经网络
    PCA
    SVM
    KNN
    Kmeans
    决策树
  • 原文地址:https://www.cnblogs.com/perfey/p/9952622.html
Copyright © 2020-2023  润新知