我面臨着一個我希望能夠獲得一些洞察力的問題。我在我的網絡應用程序中加密了視頻,將視頻解密爲BytesIO內存對象,然後使用base64編碼,從而允許用戶通過HTML5視頻播放器播放視頻。帶有base64的大文件的MemoryError
視頻本身不應該真正在文件系統上解密(每說)。但是,如果我嘗試加載大於50MB的視頻文件,則會失敗,並在web2py中顯示「MemoryError」消息。我該如何解決這個問題?
(我相信這是在base64.b64encode方法失敗)
我開發這個使用Python27和web2py的
import io
import base64
cry_upload = request.args(0)
cry = db(db.video_community.id == int(cry_upload)).select(db.video_community.ALL).first()
if cry:
if auth.user and auth.user.id not in (cry.community.members):
return redirect(URL('default', 'cpanel'), client_side = True)
filepath = os.path.join(request.folder, 'uploads/', '%s' % cry.file_upload)
form = FORM(LABEL('The Associated Key'), INPUT(_name='key', value="", _type='text', _class='string'), INPUT(_type='submit', _class='btn btn-primary'), _class='form-horizontal')
if form.accepts(request, session):
outfile = io.BytesIO()
with open(filepath, 'rb') as infile:
key = str(form.vars.key).rstrip()
try:
decrypt(infile, outfile, key)
except:
session.flash = 'Decryption error. Please verify your key'
return redirect(URL('default', 'cpanel'), client_side = True)
outfile.seek(0)
msg = base64.b64encode(outfile.getvalue().encode('utf-8'))
outfile.close()
response.flash = 'Success! Your video is now playable'
return dict(form=form, cry=cry, msg=msg)
任何意見是極大的讚賞。
解密功能禮貌的
How to AES encrypt/decrypt files using Python/PyCrypto in an OpenSSL-compatible way?
from hashlib import md5
from Crypto.Cipher import AES
from Crypto import Random
from Crypto.Random import random
def derive_key_and_iv(password, salt, key_length, iv_length):
d = d_i = ''
while len(d) < key_length + iv_length:
d_i = md5(d_i + password + salt).digest()
d += d_i
return d[:key_length], d[key_length:key_length+iv_length]
def decrypt(in_file, out_file, password, key_length=32):
bs = AES.block_size
salt = in_file.read(bs)[len('Salted__'):]
key, iv = derive_key_and_iv(password, salt, key_length, bs)
cipher = AES.new(key, AES.MODE_CBC, iv)
next_chunk = ''
finished = False
while not finished:
chunk, next_chunk = next_chunk, cipher.decrypt(in_file.read(1024 * bs))
if len(next_chunk) == 0:
padding_length = ord(chunk[-1])
if padding_length < 1 or padding_length > bs:
raise ValueError("bad decrypt pad (%d)" % padding_length)
# all the pad-bytes must be the same
if chunk[-padding_length:] != (padding_length * chr(padding_length)):
# this is similar to the bad decrypt:evp_enc.c from openssl program
raise ValueError("bad decrypt")
chunk = chunk[:-padding_length]
finished = True
out_file.write(chunk)
這裏是視圖
{{if msg != None:}}
<div class="row" style="margin-top:20px;">
<div class="video-js-box">
<video class="video-js vjs-default-skin" data-setup='{"controls": true, "autoplay": false, "preload": "none", "poster": "https://www.cryaboutcrypt.ninja/static/crying.png", "width": 720, "height": 406}'>
<source type='video/mp4; codecs="avc1.42E01E, mp4a.40.2"' src="data:video/mp4;base64,{{=msg}}" />
</video>
</div>
</div>
{{pass}}
視頻播放器注意到我傳遞編碼BytesIO數據給玩家以base64。 @Anthony - 我不是100%確定你的建議。
這裏是發生
File "/usr/lib/python2.7/base64.py", line 53, in b64encode
encoded = binascii.b2a_base64(s)[:-1]
MemoryError
你可以給解密函數的定義嗎? –
你如何確定它是一個內存問題?這是託管在什麼上的?你有多少內存可用於你的應用程序?你有多少個併發用戶? –
增加了解密方法。 @Demian - 加載視頻大於建議大小時收到MemoryError。我是這個Web應用程序的唯一用戶。我不知道我的服務器的規格。 – Maurth