Loudgain running in a Linux terminal window.
|Developer(s)||Matthias C. Hormann, Alessandro Ghedini|
|Initial release||22 June 2014|
|Stable release||0.6.8 / September 6, 2019|
|Operating system||Linux, MacOS, Windows 10|
loudgain is an open-source ReplayGain 2 tagging tool for Linux, MacOS (via Homebrew) and Windows 10 (via the Linux bash). It analyzes many types of audio files, based on the EBU R128/ITU BS.1170 standard (at -18 LUFS), and uses the well-known MP3Gain commandline syntax. Loudgain never modifies the audio data, but instead only writes the appropriate ReplayGain tags.
For mass-tagging (assuming one album per folder), loudgain comes with a bash script called
rgbpm that can be modified to the user’s needs.
Loudgain computes the ReplayGain (volume adjustment), true peak value and loudness range, using the EBU R128 algorithm for each track and (optionally) a whole album. The optional clipping prevention feature can further reduce the computed gain to a level where no clipping should occur (default -1 dBTP). Computed values are then written to the audio files as tags in a suitable tag format.
For extra versatility, loudgain also supports writing the loudness range and loudness reference values, forcing upper- or lowercase ReplayGain tags, and stripping "foreign" tags from some file types.
In case of writing ID3v2 tags, these can be specified to be either ID3v2.4 (default) or ID3v2.3. Any neccessary conversions will be done internally (i.e., converting UTF-8 frames to UTF-16 when going from ID3v2.4 to ID3v2.3).
Supported file formats
- Supported audio file formats as of version 0.6.8:
- FLAC: Values written to Vorbis comment.
- MP2, MP3: Values written to ID3v2 tags (ID3v2.3/ID3v2.4 selectable).
- (Ogg) Vorbis: Values written to Vorbis comment.
- (Ogg) FLAC: Values written to Vorbis comment.
- (Ogg) Speex: Values written to Vorbis comment.
- Opus: Values written to Vorbis comment, based on -23 LUFS Opus standard. Only
R128_ALBUM_GAINare written, but the calculated true peak value can still be used to reduce the gain values (Clipping prevention).
- MP4, M4A: Uses its own iTunes-compatible tagging system (though iTunes does not support ReplayGain). ReplayGain values are stored under
----:com.apple.iTunes:…. This is for AAC and ALAC in MPEG-4 containers.
- ASF, WMA: Values written to WMA tags, no prefix.
- WAV: Values written to the
ID3chunk, in ID3v2 (ID3v2.3/ID3v2.4 selectable) format. Using the
bextchunk (for BWF v2) isn’t (yet) supported, but won’t be destroyed on writing.
- AIFF: Values written to the
ID3chunk, in ID3v2 format.
- WavPack: Values written to APEv2 tags.
- Monkey's Audio (APE): Values written to APEv2 tags.
Command line help
Usage: loudgain [OPTIONS] FILES... loudgain 0.6.8 supports writing tags to the following file types: FLAC (.flac), Ogg (.ogg, .oga, .spx, .opus), MP2 (.mp2), MP3 (.mp3), MP4 (.mp4, .m4a), ASF/WMA (.asf, .wma), WavPack (.wv), APE (.ape). Experimental: WAV (.wav), AIFF (.aiff, .aif). Options: -h, --help Show this help. -v, --version Show version number. -r, --track Calculate track gain only (default). -a, --album Calculate album gain (and track gain). -c, --clip Ignore clipping warning. -k, --noclip Lower track/album gain to avoid clipping (<= -1 dBTP). -K n, --maxtpl=n Avoid clipping; max. true peak level = n dBTP. -d n, --pregain=n Apply n dB/LU pre-gain value (-5 for -23 LUFS target). -s d, --tagmode=d Delete ReplayGain tags from files. -s i, --tagmode=i Write ReplayGain 2.0 tags to files. -s e, --tagmode=e like '-s i', plus extra tags (reference, ranges). -s l, --tagmode=l like '-s e', but LU units instead of dB. -s s, --tagmode=s Don't write ReplayGain tags (default). -L, --lowercase Force lowercase tags (MP2/MP3/MP4/WMA/WAV/AIFF). This is non-standard but sometimes needed. -S, --striptags Strip tag types other than ID3v2 from MP2/MP3. Strip tag types other than APEv2 from WavPack/APE. -I 3, --id3v2version=3 Write ID3v2.3 tags to MP2/MP3/WAV/AIFF. -I 4, --id3v2version=4 Write ID3v2.4 tags to MP2/MP3/WAV/AIFF (default). -o, --output Database-friendly tab-delimited list output. -O, --output-new New format tab-delimited list output. -q, --quiet Don't print scanning status messages. Please report any issues to https://github.com/Moonbase59/loudgain/issues.
Closer analysis of files
-O (uppercase letter O) switch, loudgain can produce a detailed tab-separated list, ideal for redirection into a
.csv spreadsheet file and later analysis.
Simply use a command like the following and then import the
album.csv file into your spreadsheet application, specifying "tab-delimited CSV":
loudgain -O [OPTIONS] FILES... > album.csv
loudgain on Windows 10
There is currently no Windows-native version of loudgain, but it can easily be used with Windows 10’s Linux bash.
Detailed installation instructions can be found on loudgain’s GitHub page.
- Loudgain relies on standard libraries like TagLib. Linux distros (except rolling releases) sometimes deliver outdated libraries, so be sure you use the latest version of TagLib. Version 1.11.1 had a nasty bug for a while that could corrupt Ogg Vorbis files. This has been fixed in the meantime but the TagLib version not updated. Loudgain comes with a (slower) static version called
loudgain.staticin the repo’s
/binfolder that doesn’t expose the bug and can also be used on older Linux versions (like Ubuntu 14.04, Linux Mint 17).
- TagLib versions prior to Version 1.12 couldn’t write ID3v2.3 tags to AIFF files. This now works if loudgain is compiled against TagLib 1.12 or newer.
loudgain v0.1 was originally developed by Alessandro Ghedini in 2014.
Matthias C. Hormann forked this version in 2019 and took over the development of loudgain after version 0.1, starting with version 0.2.1. The latest version is 0.6.8.