Volume Normalization

[crisbtreets]

Would it be possible to allow for volume normalization durring resampling? I find that some songs are loud and some are soft. Setting all songs to a specified level durring resampling would make things sound great.

[sindre_mehus]

There are some flags in LAME to control replay gain (http://lame.sourceforge.net/doc/html/switchs.html), but it seems to be turned on by default.

If anyone knows more about this, please let us know.

[3R3]

this is not about normalizing while resampling, but using replaygain information already embeded in the files tags.

http://de.wikipedia.org/wiki/Replay_Gain
this is a quasi standard, and is used succesfully in foobar2000 audio player (and some others)

Basically, it looks for the replaygain tag in a file, and if present, adjusts loudness. Its possible to scan the file in "per file mode", or in "album mode". Then, at play time, one can choose to use per album replay gain adjust or per file adjust.

This would be a great addition to subsonic, because it requires no additional processing of files, only reading one tag and adjusting volume accordingly in the player. It would only benefit those who have scanned their music and set the replaygain tags though, but it wouldnt hurt those who didnt. And I think this replaygain tag has a real future, because its easy to implement in players and it doesnt change the actual data in the mp3 file.

edit: formatting, clarification

[Lozzy]

I've been using the oh-so-excellent mp3gain for a long time now.
I couldn't manage without it...

http://mp3gain.sourceforge.net/

[pufnstuf]

Just checking if there has been any progress with adding in support for REPLAYGAIN tags so that the volumes are more normalised when playing back via Subsonic.

This would be a killer feature as I listen to most of my tunes in shuffle play and the volume differences can be huge.

I use Squeezebox Server/ Squeezebox players when at home and it has built-in support for REPLAYGAIN, so I would love to have the same function when out and about.

Thanks sindre!

[cutandpaste]

Just use mp3gain. It can automatically process whole volumes of mp3's in either an album-centric or song-centric fashion (I strongly prefer the former).

After this is done, your music will be consistent (on whatever basis you choose) on every player that ever touches it, from Subsonic to the ruddy in-dash factory MP3 player in a Kia. The player need not understand any special tags for this to work.

And if it turns out that you don't like it, it's completely reversible.

[hawaii2000]

To suggest using Mp3gain is to assume my files are in mp3 format. Also, Mp3gain actually modifies/rewrites the audio data. Some of us have files in FLAC, a lossless audio format, and have ReplayGain tags indicating the file has been analyzed and the proper volume adjustment has been calculated. Many audio players are capable of taking the ReplayGain number and adjusting the output volume accordingly. This is the feature we would like to see with Subsonic. If not on the playback end, on the transcription end?

[madmax]

OK, I found a way to make this work.

I stream from the flac decoder to lame, with replaygain. Replaygain was calculated with Mediamonkey, but anything that writes the info to the tags will work.

In Settings > Transcodeing.

I disabled the default flac > mp3 and created one labeled "Flac to MP3"

convert from:flac
convert to:mp3
Step 1:flac -d -c --apply-replaygain-which-is-not-lossless=0tLn1 %s -
Step 2:lame -b %b - -

The apply replaygain option is not in the help, as it is newly added.
The info was found in this post:
http://www.hydrogenaudio.org/forums/lof ... 17293.html

--apply-replaygain-which-is-not-lossless[=<specification>]
Applies ReplayGain values while decoding.

WARNING: THIS IS NOT LOSSLESS. DECODED AUDIO WILL NOT BE IDENTICAL TO THE ORIGINAL WITH THIS OPTION.

The equals sign and <specification> is optional. If omitted, the default is 0aLn1 (see below).

The <specification> is a shorthand notation for describing how to apply ReplayGain. All components are optional but order is important. '[]' means 'optional'. '|' means 'or'. '{}' means required. The format is:

[<preamp>][a|t][l|L][n{0|1|2|3}]

<preamp>
A floating point number in dB. This is added to the existing gain value.

a|t
Specify 'a' to use the album gain, or 't' to use the track gain

l|L
Specify 'l' to peak-limit the output, so that the ReplayGain peak value is full-scale. Specify 'L' to use a 6dB hard limiter that kicks in when the signal approaches full-scale.

n{0|1|2|3}
Specify the amount of noise shaping. ReplayGain synthesis happens in floating point; the result is dithered before converting back to integer. This quantization adds noise. Noise shaping tries to move the noise where you won't hear it as much. 0 means no noise shaping, 1 means 'low', 2 means 'medium', 3 means 'high'.

For example, the default of 0aLn1 means 0dB preamp, use album gain, 6dB hard limit, low noise shaping.

--apply-replaygain-which-is-not-lossless=3 means 3dB preamp, use album gain, no limiting, no noise shaping.

flac uses the ReplayGain tags for the calculation. If a stream does not have the required tags or they can't be parsed, decoding will continue with a warning, and no ReplayGain is applied to that stream.

[hawaii2000]

This works great. Thanks, madmax.

Is there a way to get this to work with mp3 files as well?

[madmax]

From what I have read, by default, Lame uses replaygain if it is present in the tag. Replaygain gets calculated and then added to the tag, the audio file gets scanned twice. Because of this, it can not be done while streaming, it has to already be in the tag.

Everything in the collection here is flac, I do not have any mp3's available to test. I will test with another collection of mine at a later time.

[Sanjuro]

There are two types of replaygain, right, 'album' and 'track'? That very useful flac command lets you choose which you apply, but if lame is doing it automatically for mp3s, how do we know which one it chooses?

I've got my flacs going nicely with replaygain now (thanks very much!), but I can't be entirely sure that it's being applied to my mp3s. Placebo effect to be sure, but my mp3s seem to be slightly louder than my flacs (can't prove that in any way, of course - completely different styles of music!).

Anyway, is there anyway to check for certain?

Subsonic on Shuffle with replaygain really is bliss for long drives in the country!

[madmax]

There are two types of replaygain, right, 'album' and 'track'? That very useful flac command lets you choose which you apply, but if lame is doing it automatically for mp3s, how do we know which one it chooses?

I've got my flacs going nicely with replaygain now (thanks very much!), but I can't be entirely sure that it's being applied to my mp3s. Placebo effect to be sure, but my mp3s seem to be slightly louder than my flacs (can't prove that in any way, of course - completely different styles of music!).

Anyway, is there anyway to check for certain?

Subsonic on Shuffle with replaygain really is bliss for long drives in the country!

From what I understand, the 2 different types are only specified at calculation. The album gain scans the whole album and determines an average level, recording that to each mp3. The track gain scans the individual tracks and records the gain.

If the gain is already in the tag, that is what the replay will adjust to.

[stozher]

Album gain used if you listen all tracks from album in player (not SS flash player). Track gain (radio replayngain) used if you listen random tracks...

http://replaygain.hydrogenaudio.org/

http://en.wikipedia.org/wiki/Replay_Gain#Track-gain_and_album-gain

I search JW player web site and not found solution or plugin for replayngain. He says: this feature don't planned at this time... Only variant is a hard coded new volume gain by flac decoding option posted above.

To normalize mp3 gain use lossless program like http://mp3gain.sourceforge.net/: "MP3Gain analyzes and adjusts mp3 files so that they have the same volume.

MP3Gain does not just do peak normalization, as many normalizers do. Instead, it does some statistical analysis to determine how loud the file actually sounds to the human ear. Also, the changes MP3Gain makes are completely lossless. There is no quality lost in the change because the program adjusts the mp3 file directly, without decoding and re-encoding."

[3R3]

Just use mp3gain. It can automatically process whole volumes of mp3's in either an album-centric or song-centric fashion (I strongly prefer the former).

After this is done, your music will be consistent (on whatever basis you choose) on every player that ever touches it, from Subsonic to the ruddy in-dash factory MP3 player in a Kia. The player need not understand any special tags for this to work.

And if it turns out that you don't like it, it's completely reversible.

Using mp3gain in default mode is not reversible. You will change actual mp3 stream data. Only operating it in "tag writing" mode is reversible because it only adds a few tags like file peak, album peak, file gain, album gain, and doesnt change the actual data stream after the file header.

I know the documentation on the mp3gain site is shoddy, but I have much experience with the tool, together with foobar they make my collection smile all day, same volume and lossless, only tags rewritten. I have never paid attention if transcoded files get normalized because of the tag that is present though. Using ffmpeg for all file resampling/transcoding, anyone knows if it knows the replay gain tag?

[bemymonkey]

Consistent ReplayGain support is also something I'd love to see.

Currently I'm transcoding only FLAC (as that's the only thing I stream that's over 320kbps) and WMA to OGG. MP3 and m4a are streamed without transcoding... now how do I get all four formats to play properly including ReplayGain - WITHOUT needing to transcode MP3 and M4A needlessly?

I've written all of my ReplayGain tags using Winamp, and every song has both album and track values, in case that makes a difference. Any tips?

Specifically:

1. How can I read Winamp's ReplayGain tags from WMA? FLAC decoder seems to support applying ReplayGain as per madmax's post, but WMA...? Encoding to FLAC just so that I can decode again and apply ReplayGain seems like a bit much - not to mention that the nonstandard ReplayGain tags added to WMA by Winamp probably won't survive an encode to FLAC anyway

2. How can I apply ReplayGain without transcoding of any kind (for MP3 and M4A)? Without transcoding there's no place to enter command line switches