Help decoding waveform data from Vital presets?

Questions and Support
#1

Could anyone on the Vital team (or power users in the know) provide some insight into the encoding methods used for the samples and wave_data values in the presets?

I am building an AI model to design sounds based on user input, but am blocked by this step. After knowing the encoding method I can build a data pipeline to allow users to describe the sounds they want in natural language, and have that sound generated as a Vital preset. Any help would be appreciated!

Attached: Example of encoded wave_data

Screen Shot 2023-03-23 at 4.53.41 PM
Screen Shot 2023-03-23 at 4.53.41 PM1851×945 231 KB

#2

I’ve been trying to figure this out for a while though, no luck though. It’s probably somewhere in the source code, but I’m not c++ savy enough to find it and Vital has no documentation at all.
I’m guessing it’s a audio file without all the extra metadata and just the audio content, but I haven’t put in the effort of figuring out how to extract that into a useable format.
Good luck in your search!

#3

The code shows this:
Base64::convertFromBase64

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#4

Sweet, thanks!

For anyone else with the same question that stumbles upon this, here is an example of where the wavetable data is encoded:

json WaveSourceKeyframe::stateToJson() {
  String encoded = Base64::toBase64(wave_frame_->time_domain, sizeof(float) * vital::WaveFrame::kWaveformSize);
  json data = WavetableKeyframe::stateToJson();
  data["wave_data"] = encoded.toStdString();
  return data;
}

and here is an example of it being decoded:

void WaveSourceKeyframe::jsonToState(json data) {
  WavetableKeyframe::jsonToState(data);

  MemoryOutputStream decoded(sizeof(float) * vital::WaveFrame::kWaveformSize);
  std::string wave_data = data["wave_data"];
  Base64::convertFromBase64(decoded, wave_data);
  memcpy(wave_frame_->time_domain, decoded.getData(), sizeof(float) * vital::WaveFrame::kWaveformSize);
  wave_frame_->toFrequencyDomain();
}

toBase64 and convertFromBase64 are from the JUCE 5 module.

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