VectorFloat params incorrectly converted on Typescript before passed to WASM

[jmarcosfer]

What is the issue about?

• [x] Bug
• [ ] Feature request
• [ ] Usage question
• [ ] Documentation
• [ ] Contributing / Development

What part(s) of Essentia.js is involved?

• [x] essentia.js-core (vanilla algorithms)
• [ ] essentia.js-model (machine learning algorithms)
• [ ] essentia.js-plot (plotting utility module)
• [ ] essentia.js-extractor (typical algorithm combinations utility)

Description

Algorithms with vector_real parameter types have these parameters converted to VectorFloat on the TypeScript wrapper using the following code pattern:

let veconsets = new this.module.VectorFloat();
for (var i=0; i<veconsets.size(); i++) {
  veconsets.push_back(onsets[i]);
}

This produces an uncaught exception on the WASM side, since VectorFloat is initialized empty by default, so the loop never runs and the parameter is passed to the C++ empty. The affected algorithms are:

• AudioOnsetsMarker
• BPF
• BeatsLoudness
• CubicSpline
• FrequencyBands
• IIR
• NoveltyCurve
• RhythmExtractor
• SingleBeatLoudness
• Slicer
• Spline
• TempoScaleBands
• TempoTap
• TriangularBands

Steps to reproduce / Code snippets / Screenshots

Here is a quick browser test of the algorithms FrequencyBands and BPF. This test also includes a proposed solution using one of these options:

// use the Array -> VectorFloat conversion utility function built into essentia.js
let veconsets = this.module.arrayToVector(onsets);

let veconsets = new this.module.VectorFloat();
let i = 0;
while (veconsets.size() < onsets.length) {
   veconsets.push_back(onsets[i]);
   i++;
}

This will be addressed and solved in the PR for issue #64, with revised generated code for core_api.ts.

System info

Hardware: Dell Inc. Vostro 5490; 8,0 GiB RAM; Intel Core i7-10510U CPU @ 1.80GHz × 8 OS: Ubuntu 22.04.2 LTS, 64-bit Browser: Chrome 115.0.5790.110 (Official Build) (64-bit) essentia.js 0.1.3