Standards:

> ITU-T
ITU-T Recommendation P.833, Methodology for Derivation of Equipment Impairment Factors from Subjective Listening-Only Tests, 2001

This Recommendation gives a methodology for deriving equipment impairment factors (Ies) for digital signal processing devices, namely low bit-rate codecs with or without transmission errors. The Ie values are derived from the results of subjective listening-only tests. They are intended to be used as an input to the E-model. [see also ITU-T Recommendation G.107]

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