Initial Commit

lsb.py

@@ -0,0 +1,137 @@
+import cv2
+import numpy as np
+
+
+class img_steg:
+    def __init__(self, image_name: str = "image.png", bit_to_hide: int = 2):
+        self.image_name = image_name
+        self.bit_to_hide = bit_to_hide
+
+    def to_bin(self, data: str) -> str | list[str]:
+        """
+        Convert data to binary format as string
+        Args:
+            data: String
+
+        Returns:
+            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")
+
+    def from_bin(self, data: str) -> str:
+        """
+        Convert binary `data` back to the original format
+        Args:
+            data: String
+
+        Returns:
+            Original Data: String
+        """
+        return ''.join([chr(int(data[i:i + 8], 2)) for i in range(0, len(data), 8)])
+
+    def decode(self):
+        """
+        Decode the data hidden in the image
+        Returns:
+            Decoded Data: str
+        """
+        print("[+] Decoding...")
+        image = cv2.imread(self.image_name)  # read image
+        binary_data = ""
+        for row in image:
+            for pixel in row:
+                r, g, b = self.to_bin(pixel)
+                binary_data += r[self.bit_to_hide]
+                binary_data += g[self.bit_to_hide]
+                binary_data += b[self.bit_to_hide]
+        # Split by 8 bits
+        all_bytes = [binary_data[i: i + 8] for i in range(0, len(binary_data), 8)]
+        # Convert from bits to characters
+        decoded_data = self.from_bin(''.join(all_bytes))
+        if decoded_data.endswith("===="):
+            decoded_data = decoded_data[:-4]
+        return decoded_data
+
+    def encode(self, secret_data: str = "Hello World") -> np.ndarray:
+        """
+       Encode the secret data in the image
+       Args:
+           secret_data: str
+
+       Returns:
+           Encoded Image: np.ndarray
+       """
+        image = cv2.imread(self.image_name)  # read image
+        n_bytes = image.shape[0] * image.shape[1] * 3 // 8  # Max bytes to encode
+        print("[*] Maximum bytes to encode:", n_bytes)
+        secret_data += "===="  # Stopping Criteria
+        if len(secret_data) > n_bytes:
+            raise ValueError("[!] Insufficient bytes, need a bigger image or less data")
+        print("[*] Encoding Data...")
+
+        # Convert bit to hide position
+        bit_to_hide = 2 - self.bit_to_hide
+        data_index = 0
+        binary_secret_data = self.to_bin(secret_data)  # Convert data to binary
+        data_len = len(binary_secret_data)  # size of data to hide
+        for row in image:
+            for pixel in row:
+                r, g, b = self.to_bin(pixel)  # Convert RGB Values to binary format
+                if data_index < data_len:
+                    r = list(r)
+                    r[bit_to_hide] = binary_secret_data[data_index]  # hide data into least significant bit of red pixel
+                    pixel[0] = int(''.join(r), 2)
+                    data_index += 1
+                if data_index < data_len:
+                    g = list(g)
+                    g[bit_to_hide] = binary_secret_data[data_index]
+                    pixel[1] = int(''.join(g), 2)
+                    data_index += 1
+                if data_index < data_len:
+                    b = list(b)
+                    b[bit_to_hide] = binary_secret_data[data_index]
+                    pixel[2] = int(''.join(b), 2)
+                    data_index += 1
+                if data_index >= data_len:
+                    break
+        return image
+
+
+def main():
+    print("Welcome to Image Steganography")
+    print("1. Encode\n2. Decode\n3. Exit")
+    choice = int(input("Enter your choice: "))
+    if choice == 1:
+        image_name = input("Enter name of image to encode: ")
+        secret_data = input("Enter data to encode: ")
+        bit_to_hide = int(input("Enter bit to hide (1-8): "))
+        encoded_image = img_steg(image_name, bit_to_hide).encode(secret_data)
+        cv2.imwrite("encoded_image.png", encoded_image)
+        print("Image Encoded Successfully")
+    elif choice == 2:
+        image_name = input("Enter name of image to decode: ")
+        bit_to_hide = int(input("Enter bit to hide (1-8): "))
+        decoded_data = img_steg(image_name, bit_to_hide).decode()
+        print("Decoded Data:", decoded_data)
+
+
+if __name__ == "__main__":
+    main()
+    
+# FOR REFERENCE
+# Welcome to Image Steganography
+# 1. Encode
+# 2. Decode
+# 3. Exit
+# Enter your choice: 2
+# Enter name of image to decode: encoded_image.png
+# Enter bit to hide (1-8): 5
+# [+] Decoding...
+# Decoded Data: abc123abcasdf====