如何将字节转换为字符串？

Question

I have a bytes and I want to convert it into string in python ?

These are the bytes that I want to convert:

b'\xfeD1\xc2B\xac\xf86Mx\xc1\x0e\xa4\xe2x\x0c,\xd4\x1a\xb1'

but I am not able to convert it into normal characters.

Also I am providing the above byte as input.

I had tried:

my_str = b'\xfeD1\xc2B\xac\xf86Mx\xc1\x0e\xa4\xe2x\x0c,\xd4\x1a\xb1'.decode()
print(my_str)

and the error that I am getting is:

Traceback (most recent call last):
  File "E:/Mainproject.py", line 39, in <module>
    my_str = b'\xfeD1\xc2B\xac\xf86Mx\xc1\x0e\xa4\xe2x\x0c,\xd4\x1a\xb1'.decode()
UnicodeDecodeError: 'utf-8' codec can't decode byte 0xfe in position 0: invalid start byte

Edit:1 This is the code i used to encode the text. Here i am trying to some pn sequence to encrypt an inputed text and the resultant output that i am getting is a byte. Now i want to create another program that takes this byte as input and decode it into plain text.

from pylfsr import LFSR

# The initial state
state = [0,0,0,1,0,1,0,1,0,1,1]
# The LFSR polynomial use a primitive polynomail to get maximum period length
poly = [2,2,3,4,2]
l = LFSR(fpoly=poly, initstate =state)
print(l)
message = input().encode()
ciphertext = b""

# generate all LFSR sequence
allseq = l.runFullCycle()
seq = ""
seq_index = 0

# Convert LFSR bits into a string
for x in allseq:
    seq += str(x)
for counter in range(len(message)):
    ran_seq = seq[seq_index: seq_index+8]
    # Now encrypt by XOR convert to bytes and append to ciphertext
    # print(type(message[counter]),message[counter],type(ran_seq),ran_seq,int(message[counter]^int(ran_seq)))
    ciphertext += bytes([int(message[counter]) ^ int(ran_seq, 2)])
    # print(ciphertext)
    seq_index += 8  # Move sequence to Next byte

print(ciphertext)

Answer 1

decode converts bytes to str . encode converts str to bytes .

my_str = b'\xfeD1\xc2B\xac\xf86Mx\xc1\x0e\xa4\xe2x\x0c,\xd4\x1a\xb1'.decode()

Answer 2

You need to use latin1 encoding but this have consequences of if these bytes are non latin characters you will end up with Mojibake character which seems to be the case in your situation. Can you say what kind of string this is?

my_str = b'\xfeD1\xc2B\xac\xf86Mx\xc1\x0e\xa4\xe2x\x0c,\xd4\x1a\xb1'
print(my_str.decode("latin1"))

EDIT: You are trying to decode encrypted ciphertext and get your text back un tacked which is what encryption try to prevent, To get your text back you will have to decrypt first then decode use this code:

from pylfsr import LFSR

state = [0,0,0,1,0,1,0,1,0,1,1]
poly = [2,2,3,4,2]
l = LFSR(fpoly=poly, initstate =state)
print(l)
message = input("Enter message to encrypt: ").encode()
ciphertext = b""

allseq = l.runFullCycle()
seq = ""
seq_index = 0

for x in allseq:
    seq += str(x)
for counter in range(len(message)):
    ran_seq = seq[seq_index: seq_index+8]
    ciphertext += bytes([int(message[counter]) ^ int(ran_seq, 2)])
    seq_index += 8  # Move sequence to Next byte

print(ciphertext)
ciphertext_file_name = "ciphertext"
with open(ciphertext_file_name, "wb") as out_file:
    out_file.write(ciphertext)

# Read ciphertext and decrypt it
with open(ciphertext_file_name, "rb") as in_file:
    ciphertext = in_file.read()
    seq_index = 0
    plaintext_again = b""
    for counter in range(len(ciphertext)):
        ran_seq = seq[seq_index: seq_index + 8]
        plaintext_again += bytes([int(ciphertext[counter]) ^ int(ran_seq, 2)])
        seq_index += 8  # Move sequence to Next byte
    print(plaintext_again.decode("latin1"))