QUOTE (2Bdecided @ Aug 5 2013, 11:35) <{POST_SNAPBACK}>
It is fine to use a new calculation method with a new reference loudness, but the values must be converted to the original reference loudness before being written to ReplayGain tags. That way, loudness matching will work on all ReplayGain compatible players across all ReplayGain tagged files.
Hi. I agree.
I watched this short clarification:
Florian Camerer (2012) ITU BS.1770-2 Gating Scheme, http://www.youtube.com/watch?v=Y-zhAEu5nVo
I believe much of the confusion is because loudness metering and loudness normalization scheme are confounded. These are two separate dimensions but are NOT presented in an orthogonal way. A system should clearly indicate which method was used for measuring loudness (loudness metering) and which gain adjustment scheme was used for loudness normalization (leveling).
After a forum exchange with Peter Belkner (author of R128GAIN) and reading the standards, this is my -tentative- understanding of loudness metering and normalization.
(1) LOUDNESS METERING
(1.1) PROGRAMME LOUDNESS = single value to indicate integrated loudness for duration of the programme (track / album)
Two options:
(1.1.1) Classic Replaygain algorithm (2001).
(1.2.1) ITU BS. 1770 algorithm. Including gating function when signal drops below a certain point, specified as of revision ITU-R BS.1770-2 (03/2011). Latest: ITU-R BS.1770-3 (08/2012).
(1.2) LOUDNESS RANGE
(1.2.1) EBU-128 specified as difference between low and high percentiles of distribution of loudness as measured with ITU BS. 1770 algorithm including gating
(2) LOUDNESS NORMALIZATION / LEVELING
Loudness leveling of programmes/music compliant to:
(2.1) EBU-R128 norm, using -23 LUFS as target level.
(2.2) Classic ReplayGain 1.0 spec, reference -89 dBFS. Only applicable if (1.1.1) was used.
(2.3) ReplayGain 2.0 spec ("RG2"), mapping Loudness (L) metered with (1.2.1) onto dB's using empirical formula: RG2gain = -18 - L
(2.4) ATSC-A/85, using -24 LUFS
Is that how you see it also?