R128GAIN v0.8.4 released:
[blockquote]http://sourceforge.net/projects/r128gain/files/[/blockquote]What's new?
Page 12:
Recently (September 2010), the EBU has submitted the suggestion to the ITU to include the relative gating method into BS.1770. At the subsequent ITU meeting this suggestion was accepted, albeit with a slightly lower threshold level of -10 LU below the ungated loudness level. According to the tests of PLOUD, the results with a relative gate of -10 LU are only marginally different from -8 LU. Therefore, once the -10 LU gate is published in the next revision of ITU-R BS.1770, it will also be incorporated into EBU R 128 and the accompanying documents, particularly EBU Tech Doc 3341.
With R128GAIN v0.8.4 it's possible to parametrize the BS.1770 gate:
The range from -10.0 LU to -8.0 LU is considered EBU R128 compliant.
The command line version offers an respective "--gate" option:
$ r128gain --help
An EBU R128 (http://tech.ebu.ch/loudness) compliant loudness scanner.
For details refer to "http://r128gain.sourceforge.net/".
Usage: r128gain [options] (file|directory)+ [-o <directory> [flac|mkv]]
Options:
--r128 Run in EBU R128 compliant mode (default).
--rg Run in ReplayGain compliant mode.
--r128-compatible Calibrate output according to EBU R128.
--rg-compatible Calibrate output according to ReplayGain.
--gate=<float> R128 gate (-10.0 .. -8.0, default: -8.0).
--rg-calibration=<float> Aequivalent to use for ReplayGain
loudness (default: -18.0).
--true-peak=on,--true-peak Up-sample for peak determination (default).
--true-peak=off,--fast Switch off up-sampling.
--mono=off Treat mono as stereo (default).
--mono=on,--mono Don't treat mono as stereo.
--in-place Allow overwriting of files in place.
--loglevel=<integer> Set FFmpeg loglevel.
--regression Calculate linear regression between EBU R128
and ReplayGain.
--duration Print out duration.
--version Display version information.
--help Display this information.
Also interesting:
Informal tests conducted by
members of the EBU PLOUD group have shown that the difference in the loudness measurement
with and without the -8 LU relative gate of programmes with a small to medium loudness range are
around 0 – 1 LU.
It appears that this is true for almost all test cases except the "Authentic programme 2, stereo, wide Loudness Range (WLR) programme segment; similar in genre to a movie/drama" (the last one):
$ r128gain --gate=-10.0 ../sounds/ebu-loudness-test-setv01
SoX successfully loaded.
FFmpeg successfully loaded.
../sounds/ebu-loudness-test-setv01
analyzing ...
1kHz Sine -20 LUFS-16bit.wav (1/16): -20.0 LUFS, -3.0 LU (peak: 0.100733: -19.9 dBFS)
1kHz Sine -26 LUFS-16bit.wav (2/16): -26.0 LUFS, 3.0 LU (peak: 0.050508: -25.9 dBFS)
1kHz Sine -40 LUFS-16bit.wav (3/16): -40.0 LUFS, 17.0 LU (peak: 0.010260: -39.8 dBFS)
seq-3341-1-16bit.wav (4/16): -23.0 LUFS, -0.0 LU (peak: 0.071316: -22.9 dBFS)
seq-3341-2-16bit.wav (5/16): -33.0 LUFS, 10.0 LU (peak: 0.023049: -32.7 dBFS)
seq-3341-3-16bit.wav (6/16): -23.0 LUFS, -0.0 LU (peak: 0.071468: -22.9 dBFS)
seq-3341-4-16bit.wav (7/16): -23.0 LUFS, 0.0 LU (peak: 0.070849: -23.0 dBFS)
seq-3341-5-16bit.wav (8/16): -22.9 LUFS, -0.1 LU (peak: 0.100845: -19.9 dBFS)
seq-3341-6-5channels-16bit.wav (9/16): -23.0 LUFS, 0.0 LU (peak: 0.063132: -24.0 dBFS)
seq-3341-6-6channels-WAVEEX-16bit.wav (10/16): -23.0 LUFS, 0.0 LU (peak: 0.063132: -24.0 dBFS)
seq-3341-7_seq-3342-5-24bit.wav (11/16): -23.0 LUFS, -0.0 LU (peak: 0.358340: -8.9 dBFS)
seq-3341-8_seq-3342-6-24bit.wav (12/16): -23.2 LUFS, 0.2 LU (peak: 0.718297: -2.9 dBFS)
seq-3342-1-16bit.wav (13/16): -22.6 LUFS, -0.4 LU (peak: 0.100088: -20.0 dBFS)
seq-3342-2-16bit.wav (14/16): -16.8 LUFS, -6.2 LU (peak: 0.177971: -15.0 dBFS)
seq-3342-3-16bit.wav (15/16): -20.0 LUFS, -3.0 LU (peak: 0.100088: -20.0 dBFS)
seq-3342-4-16bit.wav (16/16): -24.5 LUFS, 1.5 LU (peak: 0.100073: -20.0 dBFS)
ALBUM: -21.9 LUFS, -1.1 LU (peak: 0.718297: -2.9 dBFS)
For the "Authentic programme 2, stereo, wide Loudness Range (WLR) programme segment; similar in genre to a movie/drama" there is a huge difference of about 4.5 LU.
This mirrors exactly what I've expected: The compromise towards the original un-gated BS.1770 becomes noticeable in case of high dynamics where the gate is thought for.