Added mp3_steg to do steg in mp3 files, working with 1 bit position.

Txt_Steg/txt_steg.py

@@ -14,7 +14,7 @@ class txt_steg:
         self.bit_to_hide = [8 - bit_pos for bit_pos in bit_to_hide] if bit_to_hide else [1]  # Default is LSB
         self.delimiter = "abc-123=="  # Delimiter to indicate the end of the secret data
 
-    def encode(self, secret_data: str = "Hello World"):
+    def encode(self, secret_data: str = "Hello World") -> str:
         """
         Encode the secret data into the text file
         :param secret_data: String

mp3_steg/mp3_steg.py

@@ -0,0 +1,122 @@
+import numpy as np
+
+
+class mp3_steg:
+    def __init__(self, mp3_file: str = "audio.mp3", bits_to_hide: list[int] = None):
+        """
+        Initialize the class
+        :param mp3_file: PathName of the mp3 file to encode or decode
+        :type mp3_file: str
+        :param bits_to_hide: Bit to hide the data in (1 - LSB to 8 - MSB)
+        :type bits_to_hide: list[int]
+        """
+        self.mp3_file = mp3_file
+        self.bits_to_hide = [8 - bit_pos for bit_pos in bits_to_hide] if bits_to_hide else [1]  # Default is LSB
+        self.delimiter = "12345"  # Delimiter to indicate the end of the secret data
+
+    def encode(self, secret_data: str = "Hello World"):
+        # Use struct to convert mp3 file to binary
+        with open(self.mp3_file, "rb") as f:
+            data = f.read()
+
+        # Max Bytes to encode
+        n_bytes = len(data) // 8
+
+        # Check if secret data can be encoded into mp3 file
+        print(f"Secret data length: {len(secret_data)}, Max data length: {n_bytes}")
+        if len(secret_data) > n_bytes:
+            raise ValueError(
+                f"[-] Error: Binary Secret data length {len(secret_data)} is greater than data length {n_bytes}")
+
+        # Convert secret data to binary
+        binary_secret_data = self.to_bin(secret_data)
+
+        # Add delimiter
+        binary_secret_data += self.to_bin(self.delimiter)
+
+        data_index = 0
+        encoded_data = bytearray()
+
+        print(f"[+] Starting encoding...")
+        # Encode data into mp3
+        for byte in data:
+            if data_index >= len(binary_secret_data):
+                encoded_data.append(byte)
+            else:
+                for bit_pos in self.bits_to_hide:
+                    if data_index < len(binary_secret_data):
+                        # Convert byte from int to binary string
+                        byte = format(byte, "08b")
+                        byte = list(byte)
+                        byte[bit_pos] = binary_secret_data[data_index]
+                        data_index += 1
+                encoded_data.append(int(''.join(byte), 2))
+
+        # Return encoded data as bytes
+        return bytes(encoded_data)
+
+    def decode(self):
+        # Use struct to convert mp3 file to binary
+        with open(self.mp3_file, "rb") as f:
+            data = f.read()
+
+        binary_data = ""
+        print(f"[+] Starting decoding...")
+        for byte in data:
+            # Add byte to binary data
+            # Convert byte from int to binary string
+            byte = format(byte, "08b")
+            # Pad byte with 0's to make sure it has 8 bits
+            byte = "0" * (8 - len(byte)) + byte
+            for bit_pos in self.bits_to_hide:
+                binary_data += byte[bit_pos]
+
+        all_bytes = [binary_data[i: i + 8] for i in range(0, len(binary_data), 8)]
+
+        decoded_data = ""
+        for byte in all_bytes:
+            decoded_data += chr(int(byte, 2))
+            # print(decoded_data)
+            if decoded_data[-len(self.delimiter):] == self.delimiter:
+                break
+
+        # Return the decoded data
+        return decoded_data
+
+    def to_bin(self, data: str) -> str | list[str]:
+
+        """
+        Convert text file data to binary format as string
+        :param data: String
+        :type data: str
+        :return: Binary Data: String | List[String]
+        """
+        if isinstance(data, str):
+            return ''.join([format(ord(i), "08b") for i in data])
+        elif isinstance(data, bytes) or isinstance(data, np.ndarray):
+            return [format(i, "08b") for i in data]
+        elif isinstance(data, int) or isinstance(data, np.unit8):
+            return format(data, "08b")
+        else:
+            raise TypeError("Type not supported")
+
+
+if __name__ == "__main__":
+
+    with open("../Txt_Steg/secret_data.txt", "r") as f:
+        secret_data = f.read()
+
+    # Encode data into mp3 file
+    mp3_steg_encode = mp3_steg(mp3_file="audio.mp3", bits_to_hide=[1])
+    encoded_data = mp3_steg_encode.encode(secret_data="Hello")
+
+    # Write encoded data to file
+    with open("encoded_audio.mp3", "wb") as f:
+        f.write(encoded_data)
+
+    # Decode data from mp3 file
+    steg_decode = mp3_steg(mp3_file="encoded_audio.mp3", bits_to_hide=[1])
+    decoded_data = steg_decode.decode()
+
+    # Print the decoded data
+    print("[+] Decoded data:", decoded_data)