Re: "Encoding Efficiency" Definition

The problem, as you note later, is that we normally specify the
compression ratio (output bitrate versus input bitrate) and test the
subjective quality of what comes out. So any codec can give a
compression ratio but not all give the same 'quality'.

The quality is subjective, and also depends on the purpose of the
listening/viewing and the ability of the listener/viewer to discern
differences. Great topic for long and meaningful discussions, bringing
in all those human touches like how we hear, see and feel. But less
easy to measure. :-)

Stefan Winkler - http://stefan.winkler.net/quality.html - discusses
ways to measure video quality quantitatively without subjective tests.
He also recently published a good book on the topic.

It isn't easy but it is a useful discussion. The idea being to try to
clarify what you mean by 'quality' and on what content under what
conditions, then find ways to quantify that and test it objectively.

Chris
=================
Chris Bore
BORES Signal Processing
www.bores.com

.

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