October 2002 | NTIA Technical Memo TM-03-398
Abstract: It is often desirable to compensate for system gain, especially before objectively estimating perceived audio or video quality from system inputs and outputs. A common approach is to scale the system output to compensate for system gain. One can take three views of the system, and this leads to three different gain compensation solutions: one that minimizes distortion, one that matches inputoutput power, and one that maximizes signal-to-distortion ratio. We derive these three solutions, describe the algebraic and geometric relationships between them, and provide a generalized result that subsumes all three. We provide audio and video examples and show that these three solutions can differ significantly. We also report some of the gain compensation choices found in the objective audio and video quality estimation literature.
Keywords: gain estimation; audio quality estimation; speech quality estimation; video quality estimation; gain compensation; system gain
For technical information concerning this report, contact:
Stephen D. Voran
Institute for Telecommunication Sciences
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