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import cv2
import numpy as np
def binary_convert(data):
"""This function converts our data into binary data."""
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.uint8):
return format(data, "08b")
else:
raise TypeError("This type is unsupported.")
def encode(image_name, secret_data):
# Reads the image
image_rows = cv2.imread(image_name)
# Gives us the maximum no. of bytes to encode.
n_bytes = image_rows.shape[0] * image_rows.shape[1] * 3 // 8
print("Maximum bytes to encode are:", n_bytes)
if len(secret_data) > n_bytes:
raise ValueError(
"Insufficient bytes,we will need a bigger image or less data.")
print("Encoding Data to Image...")
# This adds a stopping criteria, which is used to guess the
secret_data += "====="
data_index = 0
# Converts the data to binary.
binary_secret_data = binary_convert(secret_data)
# Gets the size of the data to hide.
data_len = len(binary_secret_data)
for row in image_rows:
for pixel in row:
r, g, b = binary_convert(pixel)
if data_index < data_len:
pixel[0] = int(r[:-1] + binary_secret_data[data_index], 2)
data_index += 1
if data_index < data_len:
pixel[1] = int(g[:-1] + binary_secret_data[data_index], 2)
data_index += 1
if data_index < data_len:
pixel[2] = int(b[:-1] + binary_secret_data[data_index], 2)
data_index += 1
if data_index >= data_len:
break
return image_rows
def decode(image_name):
print("Decoding data from Image...")
# Reading the Image
image_rows = cv2.imread(image_name)
binary_data = ""
for row in image_rows:
for pixel in row:
r, g, b = binary_convert(pixel)
binary_data += r[-1]
binary_data += g[-1]
binary_data += b[-1]
# Splitting the image by 8-bits
all_bytes = [binary_data[i: i+8] for i in range(0, len(binary_data), 8)]
# Now, we convert the bits to characters
decoded_data = ""
for byte in all_bytes:
decoded_data += chr(int(byte, 2))
if decoded_data[-5:] == "=====":
break
return decoded_data[:-5]
# We will assign variables as the name of the input and the output file.
input_img = "img.png" # Enter the name of your image here.
out_img = "img_out.png" # Also, update this accordingly.
# Now we can just call the encode() function to encode the image and save the data to a variable.
enc_image = encode(input_img, "Hi Folks!") # Replace "Hi Folks!" with the data you want to encode.
cv2.imwrite(out_img, enc_image) #Using OpenCV to write the result to an actual image file.
# We can decode the image by simply calling the decode() function.
decode(out_img)
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