FaustWasm

WebAssembly version of Faust Compiler for Node.js and web browsers, built with Emscripten 2.0.25

Usage

Please use a stable version of Node.js 16+ to work with this project.

Use the command line interface

Clone and get into this project:

git clone https://github.com/fr0stbyter/faustwasm
cd faustwasm

Generate WebAssembly version of a Faust DSP

For example:

rm -rf test/out # make sure you are under the faustwasm directory.
node scripts/faust2wasm.js test/mono.dsp test/out

or

rm -rf test/out # make sure you are under the faustwasm directory.
node scripts/faust2wasm.js test/poly.dsp test/out -poly

You can create standalone DSP on a web page using the same command line

rm -rf test/out # make sure you are under the faustwasm directory.
node scripts/faust2wasm.js test/rev.dsp test/out -standalone

Generate SVG Diagrams of a Faust DSP

For example:

rm -rf test/out # make sure you are under the faustwasm directory.
node scripts/faust2svg.js test/mono.dsp test/out

The main diagram should be in test/out/process.svg.

Generate or process audio files

Options:

• -bs <num> to setup the rendering buffer size in frames (default: 64)
• -bd 16|24|32 to setup the output file bit-depth (default: 16)
• -c <samples> to setup the output file length in frames, when -ct is not used (default: SR*5)
• -in <inputWav.wav> specify an input file to process
• -sr <num> to setup the output file sample rate (default: 44100) See this help:

node scripts/faust2sndfile.js -h

For example:

rm -rf test/out # make sure you are under the faustwasm directory.
mkdir test/out
node scripts/faust2sndfile.js test/p-dj.dsp test/out/p-dj.wav -c 192000 -sr 48000 -bd 24

Now the test/out/p-dj.wav should be generated.

node scripts/faust2sndfile.js test/rev.dsp test/out/p-dj-rev.wav -c 192000 -sr 48000 -bd 24 -in test/out/p-dj.wav

Use the JavaScript Module

npm i -D @shren/faustwasm

In JavaScript:

const FaustWasm = require("@shren/faustwasm");
const path = require("path");
const fs = require("fs");

const {
    instantiateFaustModuleFromFile,
    LibFaust,
    WavEncoder,
    FaustMonoDspGenerator,
    FaustCompiler,
    FaustSvgDiagrams
} = FaustWasm;

(async () => {
    const faustModulePath = path.join(__dirname, "../node_modules/@shren/faustwasm/ libfaust-wasm/libfaust-wasm.js");

    // initialize the libfaust wasm
    const faustModule = await instantiateFaustModuleFromFile(faustModulePath);

    // Get the Faust compiler
    const libFaust = new LibFaust(faustModule);
    console.log(libFaust.version());
    const compiler = new FaustCompiler(libFaust);
    const generator = new FaustMonoDspGenerator();
    const sampleRate = 48000;
    const name = "Djembe"
    const argv = ["-I", "libraries/"];
    const code = `
import("stdfaust.lib");
process = ba.pulsen(1, 10000) : pm.djembe(60, 0.3, 0.4, 1);
`;
    // Compile the DSP
    await generator.compile(compiler, name, code, argv.join(" "));
    const processor = await generator.createOfflineProcessor(sampleRate, 1024);

    // Generate SVG diagrams.
    const svgDiagrams = new FaustSvgDiagrams(compiler);
    const svgs = svgDiagrams.from(name, code, argv.join(" "));
    console.log(Object.keys(svgs));

    const out = processor.render(null, 192000);
    const wav = WavEncoder.encode(out, { sampleRate, bitDepth: 24 });

    // The wav file is generated
    fs.writeFileSync(`${__dirname}/out.wav`, new Uint8Array(wav));
})();

Use in a web browser

(async () => {
    const {
        instantiateFaustModuleFromFile,
        LibFaust,
        WavEncoder,
        FaustMonoDspGenerator,
        FaustCompiler,
        FaustSvgDiagrams
    } = await import("../node_modules/@shren/faustwasm/dist/esm/index.js");

    // initialize the libfaust wasm
    const faustModule = await instantiateFaustModuleFromFile("../node_modules/@shren/faustwasm/libfaust-wasm/libfaust-wasm.js");

    // Get the Faust compiler
    const libFaust = new LibFaust(faustModule);
    window.libFaust = libFaust;
    console.log(libFaust.version());
    const compiler = new FaustCompiler(libFaust);
    const generator = new FaustMonoDspGenerator();
    const sampleRate = 48000;
    const name = "Djembe"
    const argv = ["-I", "libraries/"];
    const code = `
import("stdfaust.lib");
process = ba.pulsen(1, 10000) : pm.djembe(60, 0.3, 0.4, 1);
`;
    // Compile the DSP
    await generator.compile(compiler, name, code, argv.join(" "));
    const processor = await generator.createOfflineProcessor(sampleRate, 1024);

    // Generate SVG diagrams.
    const svgDiagrams = new FaustSvgDiagrams(compiler);
    const svgs = svgDiagrams.from(name, code, argv.join(" "));
    console.log(Object.keys(svgs));

    const out = processor.render(null, 192000);
    const wav = WavEncoder.encode(out, { sampleRate, bitDepth: 24 });

    // The wav file is generated
    const blob = new Blob([wav], { type: "audio/wav" });
    const player = document.createElement("audio");
    player.controls = true;
    player.src = URL.createObjectURL(blob);
    document.body.appendChild(player);
    const svg = document.createElement("div");
    svg.innerHTML = svgs["process.svg"];
    document.body.appendChild(svg);
})();

Build

npm run build