LUFS Functions

[airon]

This is the discussion thread for the feature request

LUFS Functions

It asks for various LUFS metering and processing functions for Reaper. It is related to the metering request by Dannii and augments it with some broadcast-related necessities.

[timlloyd]

I don't do broadcast work, but I fully support the idea - voted +1

[musicbynumbers]

I need this too just looked at nugen one, ouch!

[airon]

Love bump.

[Joystick]

+10 for that, always looking for good standardization techniques :-)

[airon]

One month, one bump.

[planktone]

hindenburg journalist has a nice loudness meter build in
w.

[airon]

Little bump for the useful LUFS functions and metering.

Wouldn't you rather meter with the best and most useful method we have right now ?

[BrianW]

Voted.

I didn't see it mentioned in the FR, but it would be nice if the mcu-master meter could be selected to show "True-Peak" the way the current meter displays "RMS/Peak" side by side. Also, selectable between MLk (momentary LUFS) and SLk (Short LUFS), with the digital readout for Integrated at the top or bottom of the meter, along with a "reset" button.

Also, for my preference, I'd have it read the actual LUFS (ie -23) rather than having -23LU read as 0, and a user who wishes otherwise could calibrate it to his/her wishes by adjusting display gain (in LU increments, of course).

[Some Guy]

bump.........

[airon]

Bump this. 89 votes.

[ned]

What programs are there that have a loudness normalization function at the moment? (...automated like peak normalization.)

[plush2]

Originally Posted by ned

What programs are there that have a loudness normalization function at the moment? (...automated like peak normalization.)

The new version of Audition (CS6) has such a feature.

Foobar2000 also has something like this as well.

[airon]

Audition CS6, that's interesting.

Nuendo 6 will apparently have a lot of functions for this. Protools has nothing, if you don't buy a plugin that comes with an Audiosuite component for this, like NuGens $250 plugin for normalizing. Then there's their Loudness Meter plugin set, which also comes with an Audiosuite component so you can scan and then manually use something like the gain plugin to produce the final file.

NuGen's LMB($1000) is a batch processor just for the purpose of offline loudness normalization to specific specs, though I wouldn't trust anyone's dynamic compression of leveling schemes if there are any. It does have good logging and a built-in limiter for any necessary truepeak control. Great for facilities or networks. Imagine if the suggested functions were part of the batch processor of Reaper.

For static level normalization, you can measure it with the commandline tool of the libebur128 project(which I keep as my second external editor on a keyboard shortcut). That binary is no longer available at this time but I can upload it for you if you wish (win32-SSE2 and Win64 versions available).

Foobar2000, as Plush2 mentioned, has a replaygain scanner that now uses the ITU.BS-R 1770-2 method (integrated loudness scan with a G10 gate) with a target loudness of -18 LUFS. So if you want to batch convert to 0 LU = -23 LUFS, then just cut 5 dB in the conversion presets replaygain processing.

Of course none of this stuff supports time-code-locked history graphs. That would be a first. After I posted it, and many other engineers including myself asked meter manufacturers for it(such as RTW), I actually saw that idea in the Nuendo forums over at Steinberg as well. Someone else started asking for this in a two month-old post. It wouldn't surprise me if Steinberg implemented this idea for Nuendo 6.

In my humble opinion, the Cockos boys can probably get something like this going over a weekend, since the libebur128 library is MIT-license-free and works.

[airon]

A concept sketch. Any and all comments and ideas welcome. Please read the description(and critisize that too if you think it's not good).

The yellow "Time Selection for rescan.." text section to the right of the yellow'framed time selection wouldnt' appear of course. Maybe the Rescan button would light up if a time selection is made either in the graph window or the arrangement. -edit- Now it does.

There are faint grid lines for the "over" part of the graph, which the graph will then indicate in red as illustrated.

A time selection can be made for rescan or playback. Whether or not the playhead is actually repositioned when you change the time selection is controlled in the preferences. The rescan should be made with a preroll because of delay and reverb effects often being active. The context menu of the window could contain preset values in second increments and a custom setting that brings up a requester. Values should be entered in seconds, which corresponds to what probably all reverb effects use.

Left-click and drag for making a time selection. All keyboard commands applying to zoom and scroll behaviour, which includes the mousewheel-triggered actions, should apply here too without having to painstakingly recreate stuff from the arrangement setup.

No need to repeat the often lamented inconsistencies we had the midi editor. Should a separate context in the action list be made available, perhaps a reference to "As in Arrangement context" for those commands, similar to what some mouse modifier contexts do. In other words, links of one action context to another.


Commands required would be set start and end of time selection, rescan, preroll toggle on/off. Blind folks don't need this view anyway so there really wouldn't need to be commands for creating new views, changing to a different view or removing a view. Removing a view would be handled in the context menu as well, so as to prevent nasty little accidents in the fiddly little tabs.


Configuration
Baseline, maximum momentary LU, maximum LRA. Context menu is the easiest with popups of a combined text entry and dropdown menu(for presets and history).

The baseline (thick green line in the middle) is by default at 0 LU, which equates to -23 LUFS.
The Maximum Momentary LU value can be set to +9 by default. The Maximum LRA is safe at 20.

2nd Update
Updated the image to add a feedback text that appears to the left of the time selection in this view, to indicate the maximum LU, minimum LU and LRA if applicable for that selection. The LRA needs a minimum of 30 seconds iirc to get any meaningful measurements. This gives the user additional feedback and cuts down on guesswork.

The second addition is that little button-box in the top-middle of the selection. This is a function trigger to calculate the integrated LU/LUFS value of that time selection(with preroll if toggled on).

All programs are broken in to segments. Each segment has to conform to the loudness spec of the broadcaster. Thus the mixer will want to check each segment individually without having to render it to a file first. This function was suggested to be an action, but this window is the perfect place to expose that function, and only for time selections as well.

There's nothing else for the user to do on this graph but make a time selection, and in it trigger this useful function. Thus the button won't be in the way at almost any time.

[ned]

Originally Posted by airon

For static level normalization, you can measure it with the commandline tool of the libebur128 project(which I keep as my second external editor on a keyboard shortcut).

Having the scanning feature of libebur128 implemented as a type of audio file/item/selection inspector would be useful. A lot faster than having to run through the entire program in realtime while watching an LU meter just to get the integrated LU measurement.

Audiofile Engineering's Wave Editor has a neat offline analyzer function that prints out various statistics, no LU measurements though. Might be a model to base a Reaper LU inspector.
http://www.audiofile-engineering.com.../analyzer.html

[gofer]

Originally Posted by pipelineaudio

Hell yeah!!!! Imagine using this to set relative levels between songs when sequencing an album

Originally Posted by Quest The Wordsmith

My thoughts exactly!

Originally Posted by Joystick

This is an excellent suggestion!

We Game Audio folks will be more than happy to explore how those tools will work in our relatively new industry.

The internet is already hot with discussions on setting a standard for Loudness in Game Audio Development, I'm working on some special interest groups on relative matters and its great to see ideas like those in my favorite tool, if REAPER had an Internet Browser, Office Apps and Steam Store, I wouldn't want an operating system :-D

Great job Airon, thank you for taking the time to do such a detailed design document, I hope I can contribute to that great idea when our beloved Cockos devs make it true! :-)

Cheers!

1010101010

[Joystick]

It would be also cool to be able to process the items and normalize them to a selected level of loudness according to various standards, official and user-configured presets.

Also a separation of different levels in color would make a nice visual tool to take a quick look to all the session and see what's going on. Kinda like the NuGen meter does.

From my experience in game audio we don't need only the ITU-BS1770.2 standard, but also perceived loudness measuring standards for short duration sound effects in order to produce content that is relevant to the perceived loudness easily.

[airon]

The graph would make that a little easier if you spread them out over the timeline.

The request includes the ability of producing a graph per track and selecting which graph to view in a dropdown menu.

This could be interesting to line up all the VO for example, though it'll require a little trial and error, seeing what LU values should be targeted for each voice.

Not sure I'd trust the algorithm that far yet, but it's worth a try.

[airon]

In an interesting titty-twist of events, the application most of us are least likely to use has actually implemented most of the things requested here. Not that this request was overly original to begin with. It was merely practical.

That DAW is Nuendo 6. It has a loudness track, which is what Reaper would never do of course, but it does what the loudness graph view would have done. It gives you a synchronized loudness history graph that automatically updates itself. Not that Reaper really had a chance at doing this first. It has trouble limping long with its FisherPrice automation system anyway, so this being something broadcast folks will get a kick out of and more and more music mixers might, I fully expected Reaper to be eclipsed completely on this issue.

That's it for this months update. We now return to our regular scheduled waiting.

[musicbynumbers]

Reaper 5 needs this

This is the one from Nuendo.. Justin and Scwha could easily add this I reckon! I have faith in them!

[Joystick]

Wow Airon, thanks! This is very helpful :-)

[airon]

Originally Posted by musicbynumbers

Reaper 5 needs this

This is the one from Nuendo.. Justin and Scwha could easily add this I reckon! I have faith in them!

It looks a little like the Nuendo folks may have copied the idea from the FR, but I don't think that's the case.

Plenty of engineers were asking for a timecode locked loudness history before that. In fact, a guy from RTW made a presentation here in Berlin about loudness metering, pimping their produces along the way of course, and mentioned that it was the most-requested feature.

Reaper however is not in the habit of doing anything but one type of track, which is why a dockable, arrangement-view-syncable view is proposed in the feature request.

Along with that the loudness scanning functions of source files could actually be implemented at the time the peak-files are generated.

We're talking 400ms RMS with two bands of filtering, which could easily be bolted to the end of the actual peak file for easy reference, so trimmed items could still easily have their loudness measurement calculated from the data. I am assuming of course that with a 75% overlap, the RMS scan only needs to produce data every 100 ms, so one float for eash of that and it's just 40 bytes per second of audio.

The game audio folks certainly should be clawing for this. Loudness-normalizing dialogue would give you an excellent starting point to work from.

[Joystick]

Originally Posted by airon

The game audio folks certainly should be clawing for this. Loudness-normalizing dialogue would give you an excellent starting point to work from.

You are spot-on here Airon, game audio would be far easier especially with the way many designers work these days, producing content and either getting it to the developers or selling it online as stock content.

Dialogue, effects and ambiance would work great directly from render.

If this feature is developed I also have a recommendation to propose, regarding a different method of measuring data that seems to fit even better on the modern game audio design practices many people use and allows for fr better loudness control specific in sound with tiny duration like the ones used in many mobile games and apps.

Oh, and I believe the dock-able and sync-able view of the curve and also the exporting of the measurement data or even the statistics of many files would be great for control after the production and before implementation.

[Sigilus]

Still hoping for something to come of this without workarounds. Great job to all involved in defining the requirements.

[musicbynumbers]

Originally Posted by ned

What programs are there that have a loudness normalization function at the moment? (...automated like peak normalization.)

Apart from the Beta version of the SWS extension you mean?

http://sws.mj-s.com/index.php

It's just come out and it's some great work done by "Breeder". Does what you need but if it doesn't, let the SWS guys know

[airon]

Added a small list of tools that help out the Loudness Normalization-seeking user to the main request.

While we wait patiently for Cockos to implement this, there are several free or inexpensive measurement plugins you can use to at least get basic measurements done and some analysis.

• SWS Reaper Extension 2.4.0 beta 9 or higher for offline analysis and normalization - FREE
• TBAudio EBUR128 JS Analysis plugin (Reaper forum thread) - FREE
• HOFA 4U Meter, Fader & MS-Pan (VST plugin) - FREE (check settings button for EBUR128 mode)
• Melda Loudness Analyzer (VST plugin) - FREE
• Audication ACR128 (VST plugin) - FREE
• Toneboosters EBU Loudness (VST plugin w/surround-measurement, graph history and multiple measurement standards) - 20 Euros
• NuGen VisLM and more(highly configurable and well supported plugins, hardware and offline tools) - $200+ depending on product

None of these tools have all this request asks for.

[airon]

Added the link provided by user Icchan.

LUFS - the new Loudness Units. What does it mean? by Ian Shepherd

[ecc83]

Another vote for LUFS.

Dave.

[airon]

Ok, looks like we're getting some loudness normalization functions via the SWS extension. Breeder is hammering that stuff out right now and first beta tests have been positive.

In the first release it, at a minimum it looks like we're getting normalization actions based on EBU R128 recommendations. That's ITU-R.BS 1770 loudness measurement with a -10 gate. The test files all check out so far, apart from a slight departure in the LRA measurement for one file, but that's fixable if it hasn't been already.

Breeder's still hashing out details and adding/changing things but it hopefully won't be long.

[musicbynumbers]

Indeed guys.. Its going to be awesome!

[airon]

Functions to scan items and tracks for loudness values, and normalize to -23 LUFS or a value of your choice, are now available in the latest beta, v2.4.0 #5.

The functions were implemented by Breeder with the library libebur128. The beta version is available at http://www.standingwaterstudios.com/reaper


To quote from the changelog:

Analyze and normalize loudness

Functionality in general:

• Loudness is measured according to EBU 3342 standard thanks to excellent libebur128 by Jan Kokemuller
• Due to limitations in Reaper API, we can extract audio data only from certain parts of the audio chain. Chart can be found here. A few gotchas:
• You can't use item fades for extensive volume control
• If you need to use FX, current workaround is to put one item with needed FX in an empty track and measure that track

Added actions:

• SWS/BR: Normalize loudness of selected items/tracks...
• SWS/BR: Normalized loudness of selected items/tracks to -23 LUFS
• SWS/BR: Analyze loudness...

Analyze loudness dialog:

• Accessible from the Action list or Main menu > Extensions > Loudness...
• Right-click on the dialog or just click "Options" button for various settings
• Measures integrated, range, short-term and momentary loudness of selected items and tracks
• To normalize items or tracks, right-click analyzed targets in the list view - often faster than using separate actions because data for already analyzed targets in the dialog is cached (to prevent needles reanalyzing before normalization if nothing changed)
• Draw momentary and short-term loudness graph to selected envelope. Right-clicking analyzed item should reveal the feature. You can use dummy JS effects from here as a canvas for loudness graphs
• After the target is analyzed, it's possible to position edit cursor over maximum short-term and momentary loudness interval by double-clicking cells holding their measurements. There is also an option to create time selection over that part of the item/track.
• Dialog is designed to follow project state. If you rename or delete analyzed target, the change will get reflected in the dialog. For various settings relating to this, check dialog options
• Analyzing happens in a separate thread so user is free to keep on using Reaper while it's happening.