Speech Coding pp 123-130 | Cite as

Pre- and Postfiltering

  • Tom BäckströmEmail author
Part of the Signals and Communication Technology book series (SCT)


At low bitrates, basic CELP codecs have an easily recognisable distortion characteristic often described as noisiness or roughness. To reduce the perceptual distortion, we can try to identify and remove typical artefacts by filtering the decoded signal. In this chapter we present most typical postfiltering techniques such as formant enhancement and bass post filtering.


Perceptual Model Harmonic Structure Randomise Quantisation Noisy Characteristic Harmonic Peak 
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© Springer International Publishing AG 2017

Authors and Affiliations

  1. 1.International Audio Laboratories Erlangen (AudioLabs)Friedrich-Alexander University Erlangen-Nürnberg (FAU)ErlangenGermany

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