What are the methods of Audio Steganography?

In audio steganography, secret message is installed into digitized audio signal which result offend altering of binary series of the matching audio file. There are several methods are available for audio steganography which are as follows −

Low-bit encoding − Binary information can be saved in the Least Significant Bits of the sound files (same to the image files). For instance, channel capacity is 1kb per second per Hz. Thus, if it can have an 8kHz sequence, the capacity is 8kbps.

This method present audible noise. This has very low immunity to manipulation. Factors such as resampling and channel noise can simply damage the signal.

However, if the amplitude is slightly altered, such that it does not create some perceptible difference, the implementation provides high robustness to MPEG compression and some other forms of signal manipulation such as filtering, resampling and re-quantization.

Phase coding − This works by substituting the procedure of an audio segment with a reference procedure that defines data. Therefore, the original sound sequence is divided up into a sequence of N short segments.

A DFT (discrete Fourier Transform) is used to each segment and the phase difference is computed. There are new phase frames are generated for all segments. The phase and original magnitude are connected to make a new segment.

All new segments are link for the appropriated encoded output. At the receiver end, the segment length and DFT are called and the values are copied.

Spread spectrum − The encoded information is spread as much as applicable over the frequency spectrum. In Direct Sequence Spread Spectrum, the signal is spread by multiplying it by a specific maximal length pseudorandom sequence, known as chip.

The sampling cost for the host signal is used as the chip cost for coding. The start and end quanta for the procedure locking goals is taken responsibility of by the discrete, sampled characteristics of the host signal.

A higher chip cost leads to larger amount of related information. The only negative factor is random noise, introduced by the DSSS.

Echo data hiding − Echo data hiding embeds information into a signal by utilizing an echo. The data is hidden by varying three domains of the echo such as original amplitude, decay cost and offset or delay.

As the offset improves, the siganl and its echo blend. At a specific point, the human ear cannot categorize between the two and the echo is heard as extra resonance.

By utilizing two different delay times, both below the human audible level, and it can encode a binary one or zero.

The signal is divided into smaller bits, each of which is echoed to encode the desired bit. The last echoed signal is a recombination of all independent echoed areas. This signal operate exceptionally well and is the strongest code to date between audio files.

Updated on: 11-Mar-2022


Kickstart Your Career

Get certified by completing the course

Get Started