2. Digital Image Steganography

Digital image steganography is the practice of conveying hidden messages via encrypted digital images.  These encrypted messages are very difficult to uncover because they are highly compressed and no real methods of breaking these codes have been developed yet.  The images are closely related to the hidden stego message so that they are harder to detect because it is hard to differentiate between the two.  For these reasons, digital image steganography is commonly used to spread a virus or to steal information.

 These images are created by using algorithms that are designed to hide messages within digital media.  The most common disguise for image steganography is the JPEG image, due to its wide popularity.  The most widely used algorithm for hiding a steganographic image uses the least significant bit layers of an image because changes in these bits of information will not affect the appearance of an image.  This can appear as a slight distortion of pixels or a random sound from either a computer's printer or digital camera.

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