Steganography: the art of hiding information in images, audio and video

Steganography refers to the art and science of concealing secret information in other media. The information to be hidden is called the secret message and the medium in which the information is hidden is called the cover of the document or cover page.

The cover that contains the hidden message is called stego-document. The algorithms used to hide the message on the cover medium at the sender end and extract the hidden message from the stego document at the end of the receiver is called the stego system.

The word steganography is derived from the Greek words, Steganos (covered) and Grapto (writing), a practice of hiding private or sensitive information within something not normally suspected.

Steganography in the modern sense refers to information or a file that has been hidden within a digital image, video or audio file.?This science of concealing the information is done in such a way that no one suspects that the hidden information exists. Steganography is usually combined with cryptography.

When the information or a file is hidden inside a carrier file, the data is encrypted with a password. This is known as ‘stegoanalysis’.?A long time ago invisible ink was used to write information on sheets of paper and hide information. When sending important messages, one option is to send a clearly disguised message through cryptography methods; However, this is not the only means of communication. Steganography offers additional methods for the transmission of information that hides the existence of the message in the context of some other medium.

For example during World War II WWII, the German embassy sent the following encrypted message:

“PRESIDENT’S EMBARGO RULING SHOULD HAVE IMMEDIATE NOTICE. GRAVE SITUATION AFFECTING INTERNATIONAL LAW. STATEMENT FORESHADOWS RUIN OF MANY NEUTRALS. YELLOW JOURNALS UNIFYING NATIONAL EXCITEMENT IMMENSELY.

APPARENTLY NEUTRAL’S PROTEST IS THOROUGHLY DISCOUNTED AND IGNORED. ISMAN HARD HIT. BLOCKADE ISSUE AFFECTS PRETEXT FOR EMBARGO ON BYPRODUCTS, EJECTING SUETS AND VEGETABLE OILS”

Two separate ciphers provided the following hidden message:

?Pershing sails from NY June 1?, reading the first or second letter of each word.

In recent years, steganography has been the subject of much discussion related to its abuse, especially in terrorist activities. So in many legal authorities is growing concern about the use of steganography to share illegal material through multimedia files on websites. Steganalysis is a much younger discipline of steganography.

Today there are different stego methods by which we can detect and successfully prevent these criminal activities. On the other hand, there are many advantages of using steganography in the legal context, such as digital watermarking to determine copyright, ownership or more secure methods of storing important and confidential information, hence in the future a more intensive development of technology and much wider application possibilities.

Fernando Jiménez Motte Ph.D (c) EE, MSEE, BSEE

CEO of NEUROMORPHIC TECHNOLOGIES NT Robotics, Control Systems, Artificial Intelligence AI

https://fernandojimenezmotte.com/

https://neuromorphic-technologies.com/

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