  Steganography is the science of hiding digital information in such a way that
no one can suspect its existence. Unlike cryptography which may arouse
suspicions, steganography is a stealthy method that enables data communication
in total secrecy. Steganography has many requirements, the foremost one is
irrecoverability which refers to how hard it is for someone apart from the
original communicating parties to detect and recover the hidden data out of the
secret communication. A good strategy to guaranteeirrecoverability is to cover
the secret data not usinga trivial method based on a predictable algorithm, but
using a specific random pattern based on a mathematical algorithm. This paper
proposes an image steganography technique based on theCanny edge detection
algorithm.It is designed to hide secret data into a digital image within the
pixels that make up the boundaries of objects detected in the image. More
specifically, bits of the secret data replace the three LSBs of every color
channel of the pixels detected by the Canny edge detection algorithm as part of
the edges in the carrier image. Besides, the algorithm is parameterized by
three parameters: The size of the Gaussian filter, a low threshold value, and a
high threshold value. These parameters can yield to different outputs for the
same input image and secret data. As a result, discovering the inner-workings
of the algorithm would be considerably ambiguous, misguiding steganalysts from
the exact location of the covert data. Experiments showed a simulation tool
codenamed GhostBit, meant to cover and uncover secret data using the proposed
algorithm. As future work, examining how other image processing techniques such
as brightness and contrast adjustment can be taken advantage of in
steganography with the purpose ofgiving the communicating parties more
preferences tomanipulate their secret communication.
