时间戳

首页 > 解决方案 > 如何将 ascii 编码的图像数据解码为图像文件？

python - 如何将 ascii 编码的图像数据解码为图像文件？

问题描述

概述

以简洁和（相对）全面的方式处理 base64 编码图像文件的解码。

目标

首要目标

次要目标

初步假设

编码有效

这在 Python 3.6 中是可行的

尝试的解决方案

解释

我创建了一个名为Converter来处理任务的python类，具有以下功能

构造函数

实例方法

用法

__main__.py 

from Converter import *

c = Converter('ascii_image.txt', 'none')  # create Converter instance
# print(c.get_encoding_type()) # attempt to get encoding
c.convert_byte_stream_to_jpg()  # output the decoded data to image file

观察和问题

相关代码和错误信息

ConverterPython 类

from io import *
import base64
# import magic


class Converter:

    def __init__(self, file="none", str_object="none"):
        self.file = file
        self.str_object = str_object
        if file == "none" or "":
            self.isFromStringInput = True
            self.asciiString = str_object
        else:
            f = open(file, 'r')
            self.isFromStringInput = False
            # this was the source of the pad error
            #self.asciiString = f.read(file.__len__())
            # changed to ... duh!
            self.asciiString = f.read()
            f.close()

    def convert_byte_stream_to_jpg(self):
        f = open('ascii_image.jpg', 'wb')
        f.write(self.convert_ascii_to_byte_stream())
        f.close()
        return

    def convert_ascii_to_byte_stream(self):
        return base64.b64decode(self.strip_all_whitespace(self.asciiString))

    @staticmethod
    def strip_all_whitespace(s):
        return s.replace('\n', ' ').replace('\r', '').replace('\t', '').replace(' ', '')

    # def get_encoding_type(self):
    #     m = magic.MAGIC_MIME
    #     m.from_bytes(self.convert_ascii_to_byte_stream(), 'little')
    #     return m.file('./' + self.file)

错误信息

Traceback (most recent call last):
  File "/Users/auser/PycharmProjects/btobin/__main__.py", line 5, in <module>
    c.convert_byte_stream_to_jpg()  # output the decoded data to image file
  File "/Users/auser/PycharmProjects/btobin/Converter.py", line 22, in convert_byte_stream_to_jpg
    f.write(self.convert_ascii_to_byte_stream())
  File "/Users/auser/PycharmProjects/btobin/Converter.py", line 27, in convert_ascii_to_byte_stream
    return base64.b64decode(self.strip_all_whitespace(self.asciiString))
  File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/base64.py", line 87, in b64decode
    return binascii.a2b_base64(s)
binascii.Error: Incorrect padding

已验证正确编码

如果将以下<img>标记放在 html 文件中并用浏览器打开它，他们将看到正确解码的图像。这是解码图像的示例

<img src="data:image/jpg;base64,/9j/4QAYRXhpZgAASUkqAAgAAAAAAAAAAAAAAP/sABFEdWNr
 eQABAAQAAAAeAAD/4QOPaHR0cDovL25zLmFkb2JlLmNvbS94YXAvMS4wLwA8P3hwYWNrZXQgYm
 VnaW49Iu+7vyIgaWQ9Ilc1TTBNcENlaGlIenJlU3pOVGN6a2M5ZCI/PiA8eDp4bXBtZXRhIHht
 bG5zOng9ImFkb2JlOm5zOm1ldGEvIiB4OnhtcHRrPSJBZG9iZSBYTVAgQ29yZSA1LjYtYzAxNC
 A3OS4xNTY3OTcsIDIwMTQvMDgvMjAtMDk6NTM6MDIgICAgICAgICI+IDxyZGY6UkRGIHhtbG5z
 OnJkZj0iaHR0cDovL3d3dy53My5vcmcvMTk5OS8wMi8yMi1yZGYtc3ludGF4LW5zIyI+IDxyZG
 Y6RGVzY3JpcHRpb24gcmRmOmFib3V0PSIiIHhtbG5zOnhtcE1NPSJodHRwOi8vbnMuYWRvYmUu
 Y29tL3hhcC8xLjAvbW0vIiB4bWxuczpzdFJlZj0iaHR0cDovL25zLmFkb2JlLmNvbS94YXAvMS
 4wL3NUeXBlL1Jlc291cmNlUmVmIyIgeG1sbnM6eG1wPSJodHRwOi8vbnMuYWRvYmUuY29tL3hh
 cC8xLjAvIiB4bXBNTTpPcmlnaW5hbERvY3VtZW50SUQ9InhtcC5kaWQ6ZTg0NGJjNjUtYjAzZS
 00ODZiLThlYTctZDFjZTY4OGU5YTc2IiB4bXBNTTpEb2N1bWVudElEPSJ4bXAuZGlkOjM4NTBE
 Njg5Mzg2MzExRTZCOEZERTBFNjU0NTg5RUZDIiB4bXBNTTpJbnN0YW5jZUlEPSJ4bXAuaWlkOj
 M4NTBENjg4Mzg2MzExRTZCOEZERTBFNjU0NTg5RUZDIiB4bXA6Q3JlYXRvclRvb2w9IkFkb2Jl
 IFBob3Rvc2hvcCBDQyAyMDE0IChNYWNpbnRvc2gpIj4gPHhtcE1NOkRlcml2ZWRGcm9tIHN0Um
 VmOmluc3RhbmNlSUQ9InhtcC5paWQ6MjU4YjBiOTEtNGJhMC00NjI0LTg5NTUtYjU2ODg0OWIw
 OWFhIiBzdFJlZjpkb2N1bWVudElEPSJhZG9iZTpkb2NpZDpwaG90b3Nob3A6ZTllYjAwMGQtOD
 A0My0xMTc5LThhODktZjZmMjZkYTVhZGU1Ii8+IDwvcmRmOkRlc2NyaXB0aW9uPiA8L3JkZjpS
 REY+IDwveDp4bXBtZXRhPiA8P3hwYWNrZXQgZW5kPSJyIj8+/+4ADkFkb2JlAGTAAAAAAf/bAI
 QAEAsLCwwLEAwMEBcPDQ8XGxQQEBQbHxcXFxcXHx4XGhoaGhceHiMlJyUjHi8vMzMvL0BAQEBA
 QEBAQEBAQEBAQAERDw8RExEVEhIVFBEUERQaFBYWFBomGhocGhomMCMeHh4eIzArLicnJy4rNT
 UwMDU1QEA/QEBAQEBAQEBAQEBA/8AAEQgASwBLAwEiAAIRAQMRAf/EAH0AAAICAwEAAAAAAAAA
 AAAAAAAGBAUCAwcBAQEAAAAAAAAAAAAAAAAAAAAAEAABAgQDBQUDCgMJAAAAAAABAgMAEQQFIR
 IGMUFRcRNhgZEiMqFCFLHRUmJygpIjM0PBgxWywrMkRIQ1RWURAQAAAAAAAAAAAAAAAAAAAAD/
 2gAMAwEAAhEDEQA/AOgQQRUX6/N2lpLbaevXP4U7AxJJwzKljKfjAT6yvo6BrrVjyWW9xUcSeA
 G090UC9YOVSy3Z7e9WEfuEFKfYD7ZQW/TDtY6LjqFZqalWKacn8tscDL5Bhzhib+HaAZayNhOC
 W0yTLkkQC8K7WzgzIoGGx9FShP8AxI8N81TSGdZaQ42PUpgkmX3SuGeCAo7dq21VywytRpKjZ0
 3vLjwCtkXcV9zsdtuqCKpodSXleT5XB97fyMULVXctK1CKW4KNVaHDlZqJEqb7N/4fw8IBvgjF
 txDqEuNqC0LAUlQMwQcQRGUBoratqhpHat4ybZSVHiZbAOZwhf0xQO1ry9RXEZqmpJ+GSdjbey
 Y+QdnOMtYrXUfAWhsyNa+M/wBhJH8TPuhiabQ02hpsZUNpCUpG4JEgIBK1NqSrcqn7bSK6NO0e
 m64kkOLUPUMw2J3QsyE5+9x3+MT74ytm81qFggl5SxPelfnB9sQYBm0je6tNai21Dinad4ENFZ
 mptaRmkFHGRAh3jmWnwo3yhy7er7AlU4btY19RR2xCaZZaXUOBtTicFBMioyO6coCfUX6z0rpZ
 frGkOJwUnNMg9spyjYsW+8US2gpFTTOjKooIPgRsIjl0vnMWul6tylvdOlskIqVdJ1G5QIJST2
 gwF/pyoftdxe05WKzBE3KJw+8g+aQ5jHnmhphX1k2aZVDemsHaR0JUeKD5gPYR3ww/GMfS/a63
 8vjAUNzAc1na0K2IZWsc/wAz5oZYWNQn4XUVnrlGTalFhR4ZjL+/DPAc21Ol1N+qw6oqJKSgnc
 gpGUDsGMVcPOtLaupoUVrcs1FmU4DtLapZpcpThGgJVsYeqLlSssEpdU6khSZzSEnMpWHACHHW
 4b/o6SoEq6yOmRsBxnm7JTiLoWhKWqi4qIIdPRQkbQGzNRPMmL+725u5W92lWJlQzN4yk4nFB8
 YDl8SrW8Ke6Ub5SV5HkeRO05jlw8YjLQ40tTTySh1BKXEHalQ2iGDRtsFXXqrHkFTNJItqnIdb
 dzypx8IBh1ehK9P1U/dyKHMLTFV8S5ln/wCFm780on63f6dkLKT56hxCEp4yOc/2Y3f0deyX/W
 /B/egM9U21VxtDiWhOoYPWZltJRtA5icRKPWFtFqYqKtw/FFOVxhAKllacCZcDtxhjhD1VYFUL
 y7hSpnROnM6kfsrJxP2FHwMBEvmoam8KSjJ0KZskpbCiVKmJfmEYHlFTBBAT7Pd37RVGoaSHUr
 TkcaUSAUznNMth7oZH9Zs1FIU0SQxVqEv8yciEz3pWkKBPCcoTIIDdVNVba+pVhZW6Zl5UlBwn
 fnTNJMTLJe37PUFYSXadYk4xmyieHnG7MJSiFT1L1NMNK/LV+oyoZmljgtBwPywNtOVVSGaVol
 x5UmmUkmXZM7hxMAziqGqL/SBpCk0FCnrOBYxzz2HmQAO+HGKyw2Zu0UQZmF1Dhz1Dg95fAfVT
 sEWcARipKVpKFgKSoSUk4gg7jGUEAoXfRU1KftKgmeJpVmSf5at3Iwr1VHWUaslWw4weK0nL3K
 9Ptjq8a3v0lenZ7/p74DkudJ2KHjAFBRkk5lbgMT4CHio/UP8Aw239z1RY2r1f6H/Z7YBMt2mb
 vXkENGmZO154FOH1Ueow62ew0VobPRBcfWJOVC/WrsH0R2CLOCAIIIID/9k=" />

标签： pythonpython-3.ximage-processingbase64decode

解决方案

推荐阅读