提取EOF后隱藏的圖像

Question

對於隱寫術的小課，我將圖像附加到另一個圖像文件，如下所示：

my_image = open(output_image_path, "wb")
my_image.write(open(visible_image, "rb").read())
my_image.write(open(hidden_image, "rb").read())
my_image.close()

現在我想再次提取隱藏的圖像。 我該怎么做？ 我通過讀取圖像或將文件讀取為字節 stream 然后轉換它來嘗試使用 PIL，但我只得到可見圖像。

萬一這很重要，我應該指定所有圖像都保存為 .jpg 格式

Answer 1

好的，這是顯示隱藏圖像的方法：

from io import BytesIO
import cv2
from PIL import Image

with open(my_image, 'rb') as img_bin:
    buff = BytesIO()
    buff.write(img_bin.read())
    buff.seek(0)
    bytesarray = buff.read()
    img = bytesarray.split(b"\xff\xd9")[1] + b"\xff\xd9"
    img_out = BytesIO()
    img_out.write(img)
    img = Image.open(img_out)
    img.show()

Answer 2

我正在准備一個答案，就在你打字的時候添加了你的解決方案。 盡管如此，這是我的版本，能夠提取存儲在 output 圖像中的所有圖像：

from io import BytesIO
from PIL import Image

# Create "image to the world"
my_image = open('to_the_world.jpg', 'wb')
my_image.write(open('images/0.jpg', 'rb').read())   # size=640x427
my_image.write(open('images/1.jpg', 'rb').read())   # size=1920x1080
my_image.write(open('images/2.jpg', 'rb').read())   # size=1920x1200
my_image.close()

# Try to read "image to the world" via Pillow
image = Image.open('to_the_world.jpg')
print('Read image via Pillow:\n{}\n'.format(image))

# Read "image to the world" via binary data
image = open('to_the_world.jpg', 'rb').read()

# Look for JPG "Start Of Image" segments, and split byte blocks
images = image.split(b'\xff\xd8')[1:]

# Convert byte blocks to Pillow Image objects
images = [Image.open(BytesIO(b'\xff\xd8' + image)) for image in images]
for i, image in enumerate(images):
    print('Extracted image #{}:\n{}\n'.format(i+1, image))

當然，我也使用了 output 圖像的二進制數據，並使用JPEG 文件格式結構拆分二進制數據，准確地說是“圖像開始”段FF D8 。

對於我使用的圖像集，output 如下：

Read image via Pillow:
<PIL.JpegImagePlugin.JpegImageFile image mode=RGB size=640x427 at 0x1ECC333FF40>

Extracted image #1:
<PIL.JpegImagePlugin.JpegImageFile image mode=RGB size=640x427 at 0x1ECC333FF10>

Extracted image #2:
<PIL.JpegImagePlugin.JpegImageFile image mode=RGB size=1920x1080 at 0x1ECC37D4C70>

Extracted image #3:
<PIL.JpegImagePlugin.JpegImageFile image mode=RGB size=1920x1200 at 0x1ECC37D4D30>

----------------------------------------
System information
----------------------------------------
Platform:      Windows-10-10.0.16299-SP0
Python:        3.9.1
PyCharm:       2021.1.1
Pillow:        8.2.0
----------------------------------------