Speech enhancement aims to improve speech

Speech

Speech is the human faculty of speaking.It may also refer to:* Public speaking, the process of speaking to a group of people* Manner of articulation, how the body parts involved in making speech are manipulated...

 quality by using various algorithms.
The objective of enhancement is improvement in intelligibility

Intelligibility

In phonetics, Intelligibility is a measure of how comprehendible speech is, or the degree to which speech can be understood. Intelligibility is affected by spoken clarity, explicitness, lucidity, comprehensibility, perspicuity, and precision.-Noise levels:...

 and/or overall perceptual quality of degraded speech

Speech

Speech is the human faculty of speaking.It may also refer to:* Public speaking, the process of speaking to a group of people* Manner of articulation, how the body parts involved in making speech are manipulated...

 signal using audio signal processing

Audio signal processing

Audio signal processing, sometimes referred to as audio processing, is the intentional alteration of auditory signals, or sound. As audio signals may be electronically represented in either digital or analog format, signal processing may occur in either domain...

 techniques.

Enhancing of speech degraded by noise, or noise reduction, is the most important field of speech enhancement, and used for many applications such as mobile phone

Mobile phone

A mobile phone is a device which can make and receive telephone calls over a radio link whilst moving around a wide geographic area. It does so by connecting to a cellular network provided by a mobile network operator...

s, VoIP, teleconferencing systems

Teleconference

A teleconference or teleseminar is the live exchange and mass articulation of information among several persons and machines remote from one another but linked by a telecommunications system...

 , speech recognition

Speech recognition

Speech recognition converts spoken words to text. The term "voice recognition" is sometimes used to refer to recognition systems that must be trained to a particular speaker—as is the case for most desktop recognition software...

, and hearing aids
.

Algorithms

The algorithms of speech enhancement for noise reduction can be categorized into three fundamental classes: filtering techniques, spectral restoration, and model-based methods
.

• Filtering Techniques
• Spectral Subtraction Method
• Wiener Filtering
• Signal subspace approach (SSA)
• Spectral Restoration
• Minimum Mean-Square-Error Short-Time Spectral Amplitude Estimator (MMSE-STSA)
• Speech-Model-Based

See also

• audio noise reduction
• Speech coding
  Speech coding
  Speech coding is the application of data compression of digital audio signals containing speech. Speech coding uses speech-specific parameter estimation using audio signal processing techniques to model the speech signal, combined with generic data compression algorithms to represent the resulting...
  
  
• Speech interface guideline
  Speech interface guideline
  Speech interface guideline is a guideline with the aim for guiding decisions and criteria regarding designing interfaces operated by human voice. Speech interface system has many advantages such as consistent service and saving cost. However, for users, listening is a difficult task. It can become...
  
  
• Speech processing
  Speech processing
  Speech processing is the study of speech signals and the processing methods of these signals.The signals are usually processed in a digital representation, so speech processing can be regarded as a special case of digital signal processing, applied to speech signal.It is also closely tied to...
  
  
• Speech recognition
  Speech recognition
  Speech recognition converts spoken words to text. The term "voice recognition" is sometimes used to refer to recognition systems that must be trained to a particular speaker—as is the case for most desktop recognition software...
  
  
• Voice analysis
  Voice analysis
  Voice analysis is the study of speech sounds for purposes other than linguistic content, such as in speech recognition. Such studies include mostly medical analysis of the voice i.e. phoniatrics, but also speaker identification...
  
  

External links

• Speech Enhancement OGI School of Science and Engineering WebPage