How do I decode this binary string in python?

So, I have this string 01010011101100000110010101101100011011000110111101110100011010000110010101110010011001010110100001101111011101110111100101101111011101010110010001101111011010010110111001100111011010010110110101100110011010010110111001100101011000010111001001100101011110010110111101110101011001100110100101101110011001010101000000000000

and I want to decode it using python, I'm getting this error UnicodeDecodeError: 'utf-8' codec can't decode byte 0xb0 in position 280: invalid start byte

According to this webiste:

The output should be S�ellotherehowyoudoingimfineareyoufineP

Here's my code:

def decodeAscii(bin_string): binary_int = int(bin_string, 2); byte_number = binary_int.bit_length() + 7 // 8 binary_array = binary_int.to_bytes(byte_number, "big") ascii_text = binary_array.decode() print(ascii_text) 

How do I fix it?

3 Answers

Your bytes simply cannot be decoded as utf-8, just as the error message tells you.

utf-8 is the default encoding parameter of decode - and the best way to put in the correct encoding value is to know the encoding - otherwise you'll have to guess.

And guessing is probably what the website does, too, by trying the most common encodings, until one does not throw an exception:

def decodeAscii(bin_string): binary_int = int(bin_string, 2); byte_number = binary_int.bit_length() + 7 // 8 binary_array = binary_int.to_bytes(byte_number, "big") ascii_text = "Bin string cannot be decoded" for enc in ['utf-8', 'ascii', 'ansi']: try: ascii_text = binary_array.decode(encoding=enc) break except: pass print(ascii_text) s = "01010011101100000110010101101100011011000110111101110100011010000110010101110010011001010110100001101111011101110111100101101111011101010110010001101111011010010110111001100111011010010110110101100110011010010110111001100101011000010111001001100101011110010110111101110101011001100110100101101110011001010101000000000000" decodeAscii(s) 

Output:

S°ellotherehowyoudoingimfineareyoufineP 

But there's no guarantee that you find the "correct" encoding by guessing.

Your binary string is just not a valid ascii or utf-8 string. You can tell decode to ignore invalid sequences by saying

ascii_text = binary_array.decode(errors='ignore') 

It could be solved in one line:

Try this:

def bin_to_text(bin_str): bin_to_str = "".join([chr(int(bin_str[i:i+8],2)) for i in range(0,len(bin_str),8)]) return bin_to_str bin_str = '01010011101100000110010101101100011011000110111101110100011010000110010101110010011001010110100001101111011101110111100101101111011101010110010001101111011010010110111001100111011010010110110101100110011010010110111001100101011000010111001001100101011110010110111101110101011001100110100101101110011001010101000000000000' bin_to_str = bin_to_text(bin_str) print(bin_to_str) 

Output:

S°ellotherehowyoudoingimfineareyoufineP