FreeLCS Free Loudness Correction Server
[FAQ] [Features] [User Manual] [Downloads]
FreeLCS stands for Free Loudness Correction Server.
FreeLCS lets you automatically correct audio files to EBU R128 target
The software lets you easily set up a server that shares one of it's folders
to the network. Users of your network can then drop audio files to the
server for automatic loudness correction. For each processed file the server
also creates a loudness history graphics file which shows loudness
variations inside the file.
The software is very fast even on modest hardware giving 15 times faster
than realtime processing (16 bit stereo files, TruePeak measurement turned
on) on a server with one Intel Core 2 Duo processor, 2 GB Ram, 3 internal
Sata disks in software RAID 0.
FreeLCS uses other open source programs to get the job done (Linux,
libebur128, gnuplot, FFmpeg / libav-tools (optional), sox, mediainfo). All
software is free and Open Source.
More detailed information can be found in FAQ,
Features and User
2018.05.25 FreeLCS 3.5 released.
- This release supports Ubuntu 16.04, 18.04 and Debian 8 and 9.
- Patents for Dolby AC3, Mpeg 1 Layers 1, 2 and 3 (mp1, mp2, mp3 ) have
expired all over the world. These formats are now patent free and can be
used legally without paying anybody for a license. These formats (and
the Opus - format) are now enabled if you enable free formats during
FreeLCS installation. Extracting audio from these formats still require
installation of FFmpeg / Libav-tools.
- Libebur128 upgraded to the latest version 1.2.4. Libebur128
by default builds taglib into the 'loudness' executable. Taglib does not
build cleanly anymore on older distros probably due to old gcc -
versions. Because of this building taglib with libebur128 is disabled on
Debian 8 and Ubuntu 16.04. Taglib is used to read and write metadata
into files (For Example ID3 - data in mp3 files), so you probably don't
need it for anything anyway. https://en.wikipedia.org/wiki/TagLib
2017.08.30 FreeLCS 3.4 released.
- This release supports Ubuntu 14.04, 16.04 and Debian 8 and 9.
- Libebur128 is upgraded to the latest version 1.2.2. The new version
uses a new method to calculate true peak values. I'm testing each new
FreeLCS release with the same set of 214 files (35 GB). 192 of
them measure the same truepeak value as with the previous version of
libebur128. The rest of them get mostly a lower truepeak value than
before. Loudness measurement with the new version of libebur128
gives the same results as before.
- Libebur128 version 1.2.2 source archive is included in the FreeLCS
installation package. So now you don't have to have an internet
connection while you install FreeLCS as long as you have access to a
local Debian / Ubuntu package repository.
- Ubuntu 14.04 and 16.04 dropped the ram disk driver (brd module) from
the kernel in the middle of the support cycle. Updated kernel does no
longer include the brd module built in. Debian also does not load brd by
default, so FreeLCS 3.4 now handles loading of the brd module
automatically if the module is not loaded or built into kernel.
- If you need to disable the smb protocol version1 then remove the
character # from smb.conf in front of line: # server min protocol = SMB2
2016.07.01 FreeLCS 3.3 released.
- This release supports Ubuntu 14.04 and 16.04 and Debian 8. Support for
Ubuntu 12.04 and Debian 7 is dropped.
2013.03.11 Released introductory
material about EBU R128 recommendation and FreeLCS. This version is in
Finnish language only. The material tries to explain R128 concepts and
FreeLCS usage in the point of view of a common user. Read it here:
Older news can be found here.
- Automatically loudness corrects audio files to conform with EBU R128
- Very easy to use, just drop in your file and copy back the loudness
- Creates loudness history graphics that allows the user to see how
loudness varies inside a file (example picture below).
- Supports channel counts from mono to 5.1.
- Supports EBU TruePeak measurement.
- Uses a protective limiter to keep peaks in the allowed range where
- Takes advantage of multiple processor cores to run calculations
- User is able to define how many audio files are processed at the same
time, limited only by available cpu processing power and hard disk
- Supports writing loudness measurement results to a machine readable
- Modest hardware requirements, runs fine with only 2 GB of ram.
- Can be run inside a virtual machine, no need for physical hardware.
- Fast processing. On typical hardware you can expect processing to be
10 - 20 faster than realtime.
- Cleans up automatically by deleting all files after a set time delay.
- Sends possible error messages to the admin by email.
- If user installs FFmpeg or libav-tools
then additional features becomes available:
- The wide range of FFmpeg / libav-tools supported formats can be
- Support for multistream files, all audio streams are extracted and
- Extract audio from wrappers containing both video and audio.
- Remix audio from MXF files to required mixes before loudness
- All software is free and Open Source. Install in as many computers as
- Runs on the free Linux operating system, no need to pay for
proprietary os installation.
- Easy to integrate in many workflows.
- Written in Python 3.
- More specific information can be found in the FAQ.
Click here to go
to the download page (User manual is included in the download)
Click here to go to the User manual.
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