HydrogenAudio

Hydrogenaudio Forum => General Audio => Topic started by: jcoalson on 2006-07-06 16:28:02

Title: replaygain reference level tag?
Post by: jcoalson on 2006-07-06 16:28:02
is there a standard or at least a consensus on what the name of the tag for storing the replaygain reference level should be?  I was planning to add that to flac/metaflac.
Title: replaygain reference level tag?
Post by: Cartman_Sr on 2006-07-06 17:09:17
That would be a useful thing to have. How about REPLAYGAIN_REFERENCE? I don't know.

Can I make another request for metaflac? Multi-line tags support for metaflac. I know tag.exe works well for this purpose, but it would be good to have multi-line tags sort of "officially sanctioned" in flac.
Title: replaygain reference level tag?
Post by: kjoonlee on 2006-07-06 17:17:13
When vorbisgain was being developped, I think there was some discussion about the tag names.

At first vorbisgain used RG_TPEAK (I think it was), RG_APEAK, and RG_TGAIN, but the names were later switched to REPLAYGAIN_TRACK_PEAK etc. in favour of clarity and Googlability.

Vorbis comments are meant to be human-readable and short. REPLAYGAIN_TRACK_PEAK is human readable, and the tag contents are easily machine parsable.

IMHO, REPLAYGAIN_TARGET_LOUDNESS or REPLAYGAIN_REFERENCE_LOUDNESS or something similar would be best.

---

But would it necessary? 89 dB is almost always used.

edit: Correction. Track gain used to be called radio and album gain used to be called audiophile, so it couldn't have been RG_TPEAK.
Title: replaygain reference level tag?
Post by: Alex B on 2006-07-06 18:04:30
But would it necessary? 89 dB is almost always used.


At least J. River uses 83 dB by default in Media Jukebox and Media Center as originally proposed. They implimented it already in late 2001/early 2002 during the Media Jukebox v. 8 development. Though they also use proprietary tags for storing the info (at that time there was no standard yet). However, it would be good to develop a standard for storing the used reference. For example, if someone would like to make a converter that converts between different Replay Gain tag implimentations it would be necessary to know the used reference.
Title: replaygain reference level tag?
Post by: kjoonlee on 2006-07-06 18:17:02
LAME used to use 83 dB but they switched to 89. Maybe they should switch too?
Title: replaygain reference level tag?
Post by: Patsoe on 2006-07-06 20:40:40
I always wondered why the protocol doesn't just store the calculated level. So if your track has an average level of 90dB, just store it as "90dB". Then the player always gets the relative gains right, regardless the reference level it uses internally.

How about introducing "REPLAYGAIN_ABS_LEVEL"?
Title: replaygain reference level tag?
Post by: David Nordin on 2006-07-06 21:21:19
relative to 0dBFS
Title: replaygain reference level tag?
Post by: jcoalson on 2006-07-06 22:50:36
well, I could have sworn that this tag was already being done somewhere.  ok, I will just blaze a trail with REPLAYGAIN_REFERENCE_LEVEL=89dB (SPL being implied).

Josh
Title: replaygain reference level tag?
Post by: kjoonlee on 2006-07-07 03:19:56
well, I could have sworn that this tag was already being done somewhere.  ok, I will just blaze a trail with REPLAYGAIN_REFERENCE_LEVEL=89dB (SPL being implied).

Josh

Don't forget to include a space between 89 and dB for consistency. ("REPLAYGAIN_TRACK_GAIN=+0.41 dB")
Title: replaygain reference level tag?
Post by: jcoalson on 2006-09-14 01:40:24
I've added the new tag to all the code in CVS, this will be in the next release.  the tag currently looks like:

Code: [Select]
REPLAYGAIN_REFERENCE_LOUDNESS=89.0 dB


is that OK with everybody?

Josh
Title: replaygain reference level tag?
Post by: Patsoe on 2006-09-15 08:00:56
Looks fine to me