Implementing-cryptography-using-python

CHAPTER
6
Using Cryptography with Images
At this point, you should be feeling confident in your ability to encrypt and
decrypt messages. In this chapter, you will expand on what you know to include
the cryptography of images. Through exercises in this chapter, you will be able
to identify problems with different modes of encryption and learn alternative
ways to get results. To complete our study of image cryptography, we will close
the chapter with steganography. Through this chapter, you will do the following:
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Gain an understanding of image and cryptography libraries
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Learn about AES modes of operations
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Explore various cryptography methods for images
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Hide and read media within an image using Python
Simple Image Cryptography
Before we get into various libraries that can be used for image cryptography, I
wanted to share a simple method that will allow you to encrypt and decrypt a
file. The entire process relies on looping through the bits of an image and then
bitwise exclusive (XOR) them with the bit and the key. To decrypt the image,
we simply reverse the XOR operation.
Implementing Cryptography Using Python®, First Edition. Shannon W. Bray.
© 2020 John Wiley & Sons, Inc. Published 2020 by John Wiley & Sons, Inc.
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