[Feature Request] Linear spectrum and bins configurable

[addy90]

I have a feature request concerning the spectrum.

Would it be possible to make the frequency spectrum configurable between linear and logarithmic representation?
Also, would it be possible to make the bins independently configurable between linear and logarithmic representation?

Currently, I guess both are fixed in logarithmic scale. With this, the visual effect as it is possible in the abadonware MusicScope is not possible, see for example some images here (only the frequency spectrum) and the software as download here.

The setting could be done as in the software SonicVisualizer, see documentation and example here. The bins and the scale (visual) can be set independently.

The main idea for me would be to combine linear bins with logarithmic frequency spectrum visualization so that the bars become equally distributed in the distinct case without loosing and instead increasing the details of the low frequencies. Also the line and area visualization would become clearer in the low frequency area. See for example a YouTube video of MusicScope how this can look here (in the video, the spectrum is set to linear mode, when you download the software yourself, you can click on the text and it changes to logarithmic mode but the bins are linear in both cases as it seems, see the images linked above from that blog post where the spectrum is in logarithmic mode but clearly has linear bins as the low frequencies are high in resolution).

If you have further questions about this, please feel free to ask!

PS: Maybe with linear bins and discrete frequencies, a setting for making the bars wider than 1px is also needed, for example to make them similar to the octave bands representation, or also additional octave bands, such as 1/48th or more? Just some notes if it does not look great from the beginning...

Thank you!

Best regards!

[TF3RDL]

The frequency scaling thing is mentioned in #30, the piecewise linear-log scaling or pseudo-logarithmic bands that changes depending on FFT size/number of bands/sample rate resembles Mel scale with 256 bands and 2205 samples FFT with range of 0Hz-20000kHz

[addy90]

Thank you for mentioning #30.
I looked further into it and you are right. I did not interpret it this way from reading the title and scrolling through the first sentences but by looking further into it, I see that the perceptual frequency scaling, especially Mel or Bark, is what I was looking for. I tried out your sketch then and the options and configurations are immense. I think integrating this (or at least a relevant part of it) would solve my feature request, too. I saw that logarithmic dB scaling combined with Mel or Bark resembles quite much what I linked above. Thanks!

[hvianna]

Perceptual scales are coming, I should have a new beta ready soon.
And you guys were right, Bark scale with linear amplitude + D-weighting has become my new favorite combo! 🤩