In digital steganography, the hidden information is typically embedded within the least significant bits (LSBs) of the host medium. For example, in an image, the LSBs of each pixel's color values can be modified to encode the secret message. This alteration is usually imperceptible to the human eye, making the steganographic process effective for covert communication.
Steganography can be applied to various types of digital media, including images, audio files, and video streams. In image steganography, techniques such as LSB replacement, pixel value differencing, and transform domain methods are commonly used. Audio steganography involves embedding data within the audio signal, often by modifying the least significant bits of the audio samples. Video steganography extends these principles to the temporal domain, embedding information within the video frames.
Steganography is used in various applications, including secure communication, digital watermarking, and data hiding. Secure communication involves sending messages that are hidden within innocuous-looking files, making it difficult for interceptors to detect the presence of the hidden information. Digital watermarking uses steganography to embed copyright information or ownership details within digital media, protecting against unauthorized use. Data hiding techniques employ steganography to conceal sensitive information within public or shared files, ensuring that only authorized parties can access the hidden data.
Despite its benefits, steganography also raises concerns about privacy and security. Unauthorized use of steganography can lead to the illegal dissemination of sensitive information, such as trade secrets or personal data. Additionally, steganographic techniques can be employed for malicious purposes, such as hiding malware or phishing attacks within seemingly innocuous files. As a result, there is ongoing research and development in the field of steganography to improve its security and detectability, as well as to develop countermeasures against its misuse.