asu-regex-js

Parser to work with SubStation Alpha Subtitles (SSA/ASS) in TypeScript and JavaScript.

Read the documentation

Try the interactive playground

Installation

Install using JSR (JavaScript Registry)

bunx jsr add @fs-frost/asu

For NPM, Yarn, etc., check out https://jsr.io/@fs-frost/asu.

Install nightly bundles

Nightly bundles for Bun, Node and browser are available on Bundles.

Examples

Check out the tests or the playground for more examples.

Parse a dialogue

import * as asu from "@fs-frost/asu";

// Update font size from 32 to 16
const text = "Dialogue: 0,1:23:45.67,2:34:56.78,Chitanda,actor,12,23,34,fx,{\\pos(182,421)}LINE 1";

const line = asu.parseLine(text);
if (line == null) {
    console.error("invalid line");
    return;
}

line.style = "Oreki";
line.content = "Some {\\i1}other{\\i0} text";

console.log(asu.lineToString(line));
// Dialogue: 0,1:23:45.67,2:34:56.78,Oreki,actor,12,23,34,fx,Some {\i1}other{\i0} text

Set tag

import * as asu from "@fs-frost/asu";

// Update font size from 32 to 16
const text = "{\\be2\\fs32}Kirino-san";
const items = asu.parseContent(text);
asu.setFs(items, 16);

console.log(asu.contentsToString(items));
// {\be2\fs16}Kirino-san

Find tag

import * as asu from "@fs-frost/asu";

// find blur
const text = "{\\blur2\\fs32}Kirino-san";
const items = asu.parseContent(text);
const tagBlur = asu.findBlur(items);
if (tagBlur == null) {
    console.error("blur not found");
    return;
}

tagBlur.value = 4;
console.log(asu.contentsToString(items));
// {\blur4\fs32}Kirino-san

Create tag

import * as asu from "@fs-frost/asu";

// Create pos
const text = "{\\be2\\fs32}Kirino-san";
const items = asu.parseContent(text);
asu.setPos(items, -20, 67.9);

console.log(asu.contentsToString(items));
// {\be2\fs32\pos(-20,67.9)}Kirino-san

Development

Requirements

• Bun (JavaScript runtime)

Install JS dependencies

bun install

Run tests

bun test --coverage

Applications using Asu

• Asu for SyncRajo Fansub
• Asu Playground