Replace ruby-audio with the audiowaveform command-line utility

[Manfred]

I don't mind if this doesn't get merged, just a suggestion.

• Removes dependency on ruby-audio and lame
• Adds dependency on audiowaveform
• Re-implements Waveform to use audiowaveform to generate waveform data for an audio file.

The ruby-audio gem hasn't been updated for 10 years and doesn't seem likely to get any attention. Currently it doesn't compile on M1 macs, probably because they have their headers is /opt/homebrew and the gem setup doesn't look for the libsndfile headers properly.

Anyway, using audiowaveform reduces the number of direct dependencies and makes the code slightly simpler.

Deployment note

Make sure to install audiowaveform;

sudo add-apt-repository ppa:chris-needham/ppa
sudo apt-get update
sudo apt-get install audiowaveform

Visual changes

The algorithms used by audiowaveform probably means the waveforms will look slightly different than before.

[sudara]

Thanks Manfred! I’m traveling today but I’ll take a look soon!

[sudara]

The algorithms used by audiowaveform probably means the waveforms will look slightly different than before.

Are the example images you posted here generated by audiowaveform? We spent some time tweaking the waveform in the past to make it smoother w/ RMS and fewer points, but it looks like that's preserved here (thanks!)

[Manfred]

@sudara Yes, those are examples generated with the branch and audiowaveform.

[sudara]

Really appreciate this branch now that I'm on an M1 :)

Merry Christmas! 🌟