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2017 | OriginalPaper | Buchkapitel

9. Pre- and Postfiltering

verfasst von : Tom Bäckström

Erschienen in: Speech Coding

Verlag: Springer International Publishing

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Abstract

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.

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Fußnoten
1
Note that in the interest of clarity, we use here a significantly different notation from the one applied in original publications [5, 10].
 
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Metadaten
Titel
Pre- and Postfiltering
verfasst von
Tom Bäckström
Copyright-Jahr
2017
DOI
https://doi.org/10.1007/978-3-319-50204-5_9

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