subtitle-transform

Parses various subtitle formats (VTT/TTML/TTAF) into a type called SubtitleData.

There are various generators that take SubtitleData and emit text (SRT/ASS).

Usage

CLI

npm i -g subtitle-transform

With a file:

subtitle-transform --input=ep1.vtt --inputFormat=vtt --outputFormat=ass

or pipe:

cat ep1.vtt | subtitle-transform --inputFormat=vtt --outputFormat=ass

You can also pass --timestampSkew=-2.1 to adjust timestamps.

Library

npm i -S subtitle-transform

import { parseTT, generateASS } from 'subtitle-transform';

const inputContents = `<?xml version="1.0" encoding="utf-8"?>
  <tt xmlns="http://www.w3.org/2006/10/ttaf1" xml:lang="en" xmlns:ttm="http://www.w3.org/2006/10/ttaf1#metadata">
  <head>
    <!--Created on 1/11/2011 at 00:30:00-->
    <metadata>
      <ttm:title>
        Yellow eggs and potatoes
      </ttm:title>
      <ttm:copyright>
        Paul
      </ttm:copyright>
    </metadata>
    <styling>
      <style id="s0" tts:backgroundColor="black" tts:fontStyle="normal" tts:fontSize="16" tts:fontFamily="sansSerif" tts:color="white" />
      <style id="s1" style="s0" tts:color="yellow" />
    </styling>
  </head>
  <body tts:textAlign="center" style="s0">
    <div>
      <p begin="00:01:57.32" id="p0" end="00:01:58.36">First caption!</p>
      <p begin="00:02:11.44" id="p3" end="00:02:16.44">A what<br />oh</p>
      <p style="s1" begin="00:03:01.88" id="p14" end="00:03:04.64"><span tts:color="white">This line is white<br /></span>This line is something else</p>
    </div>
  </body>
</tt>`;

const subtitleData = parseTT(inputContents, {});
const output = generateASS(subtitleData, { enableStyles: true });

console.log(output);

Progress

Parsing

Generating

Resources used: