Disco Mix video extract, featuring simulated spectrum analyzer LEDs

I occasionally create audio mixes of old disco/pop/dance songs to play at parties. I shared on of them on YouTube a few years ago and to my astonishment, the number of views has increased from 1000 to almost 750,000. :open_mouth:

So I’m making another video and I will post it as well to see what will happen. I’m considering the layout shown in this extract:

(Best viewed full screen at 1080p)

In Shotcut, I used the Audio Spectrum Visualization filter and the Mask: From file filter to overlay fake LEDs on an image of the BDS PP-131 spectrum analyser.


Thank you for sharing. It brings me great joy to see the Audio Spectrum filter used in this way. This is exactly why I created that filter!

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Thanks for the comment.
I love that filter. Depending on the mask used and the colors chosen, you can simulate pretty much any kind on LED VU-meter.

By the way @brian I have a request if you don’t mind. Currently, the minimum amount of bands allowed is 5. Could you change it to 1 instead?

This would make it easier to simulate a stereo VU-meter like this one

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A propos de ce filtre, il y a une autre anomalie (Bug ?)
Réglez Type sur ‘barre’
Enregistrez et quittez SC
Lorsque vous ré-ouvrez le projet, Type est réglé sur ‘line’

About this filter, there is another anomaly (Bug ?)
Set Type to ‘bar’.
Save and exit SC.
When you re-open the project, Type is set to ‘line’.

Very cool video, MB! Of course, anything that starts off with Toto has to be good, right? :slight_smile:

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I changed it to 2 for the 21.12 release. But this does not simulate a VU meter because the two bars will represent different frequency bands, not different channels. Maybe I should also make an audio level visualization filter.

Thanks for your report. This is fixed for the 21.12 release.

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Hi @brian and thanks.

That’s why I was suggesting we’d be allowed to show just one band. One Audio Spectrum filter for the left channel, one for the right channel and you have a stereo VU-meter.

Since the goal is to simulate, not emulate (often for just a short period of time), I don’t mind if the meter doesn’t show accurately the db level of each channel.

I missed that part :face_with_hand_over_mouth:
I would like that yes!

That’s really cool

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I tototally agree :slight_smile: Thanks

Thank you!


If you ever create that Audio level filter, would it be possible to add an option to adjust how accurate the bars are?

Meaning that you could set it, let’s say to 10 pixels, and the bars would go up and down in blocks of 10 pixels. That would prevent from producing fractions of LEDs when using a mask. Like you can see in this example:


Of course, that option would also be useful in the Audio Spectrum Visualization filter settings. :innocent:

Also, there is a problem similar to the one reported above by @Namna concerning the Spectrum Color parameter.

  1. Set it to 2 (or more) colors
  2. Select another filter
  3. Go back to the Audio Spectrum filter
  4. Spectrum Color displays 1 colors


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I have a draft implementation of this. I am not sure if it will make it in the 21.12 release. Stay tuned.

I also have a fix for this. It will either be in the 21.12 release, or the following release.

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Try shadertoy.com for EQ displays, load a mp3 n screengrab, maybe?

I wouldn’t know how to code a spectrum analyzer or a VU-meter with Shadertoy and make it react to an actual music track in Shotcut. Plus, unless I’m mistaken, to use shaders, you need to be at least a bit familiar with a software like Natron. For the mere mortal, the Audio Spectrum Visualization filter is a lot easier to use in my opinion.

This fix will be in the 21.12 release.

I think this is pretty much ready to go for the next release. Here is a screenshot:

The new Audio Level Visualization has two types: Bar and Segment. The bar type is the same as the Spectrum Visualization Filter bar type. The Segment type is new. It divides the bar into one segment for each color specified. The segments to not have a gradient - they match the exact color specified by the user.

The “Segment Gap” setting sets the space (gap) between each segment. The “Thickness” setting modifies the width of each segment.

I also added the “Segment” type to the Spectrum Visualization Filter.

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This looks great! And it’s fully customizable. Thanks a lot @brian, can’t wait to try it.

Hi @brian. I’ve been playing a bit with the new Audio Visualization filters and so far, I’m very pleased.

I will maybe come up with one or two suggestions after more tests, even if I know it will not be a priority.

I found one little bug today in Audio Spectrum Visualization:
The Segment Gap setting goes back to zero when you leave the filter and come back to it.

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