@bbc/stt-align-node

Stt-align-node

node version of stt-align by Chris Baume - R&D.

Work in progress

Setup - development

git clon [e-mail]:bbc/stt-align-node.git

cd stt-align-node

 npm install

Setup - in production

npm install @bbc/stt-align-node

Usage

Usage for alignment

const alignJSONText = require('./index.js');

const transcriptText = 'There was a day, about 10 years ago, when I asked a friend to hold a baby dinosaur robot upside down. ';

const transcriptStt = { 
    words: [
    { start: 13.05, end: 13.21, word: 'there' },
    // { start: 13.21, end: 13.38, word: 'is' },
    { start: 13.38, end: 13.44, word: 'a' },
    // { start: 13.44, end: 13.86, word: 'day' },
    // { start: 13.86, end: 14.13, word: 'about' },
    { start: 14.13, end: 14.37, word: 'ten' },
    // { start: 14.37, end: 14.61, word: 'years' },
    { start: 14.61, end: 15.15, word: 'ago' },
    { start: 15.44, end: 15.67, word: 'when' },
    // { start: 15.67, end: 15.82, word: 'i' },
    // { start: 15.82, end: 16.19, word: 'asked' },
    // { start: 16.19, end: 16.27, word: 'a' },
    // { start: 16.27, end: 16.65, word: 'friend' },
    { start: 16.65, end: 16.74, word: 'to' },
    // { start: 16.74, end: 17.2, word: 'hold' },
    // { start: 17.23, end: 17.32, word: 'a' },
    // { start: 17.32, end: 17.63, word: 'baby' },
    // { start: 17.63, end: 18.13, word: 'dinosaur' },
    // { start: 18.17, end: 18.61, word: 'robot' },
    // { start: 18.72, end: 19.17, word: 'upside' },
    { start: 19.17, end: 19.56, word: 'down' } 
    ]
}

// call function 
const result = alignJSONText( transcriptStt, transcriptText);
// do something with the result
console.log(result);

See /lib/example-usage for an example that you can run with npm run example.

Example output

{ text: 'There was a day, about 10 years ago, when I asked a friend to hold a baby dinosaur robot upside down. ',
 words:
  [ { start: 13.05, end: 13.21, word: 'There' },
    { word: 'was', start: 13.215, end: 13.325 },
    { start: 13.38, end: 13.44, word: 'a' },
    { word: 'day,', start: 13.626000000000001, end: 13.84 },
    { word: 'about', start: 13.872, end: 14.239999999999998 },
    { word: '10', start: 14.118, end: 14.639999999999999 },
    { word: 'years', start: 14.364, end: 15.04 },
    { end: 15.44, start: 14.61, word: 'ago,' },
    { start: 15.15, end: 15.67, word: 'when' },
    { word: 'I', start: 15.450000000000001, end: 15.883999999999999 },
    { word: 'asked', start: 15.75, end: 16.098 },
    { word: 'a', start: 16.05, end: 16.311999999999998 },
    { word: 'friend', start: 16.35, end: 16.525999999999996 },
    { start: 16.65, end: 16.74, word: 'to' },
    { word: 'hold',
      start: 17.009999999999998,
      end: 17.142857142857142 },
    { word: 'a', start: 17.369999999999997, end: 17.545714285714286 },
    { word: 'baby',
      start: 17.729999999999997,
      end: 17.948571428571427 },
    { word: 'dinosaur', start: 18.09, end: 18.35142857142857 },
    { word: 'robot', start: 18.45, end: 18.754285714285714 },
    { word: 'upside', start: 18.81, end: 19.15714285714286 },
    { start: 19.17, end: 19.56, word: 'down.' } ] }

There are other utilities, see src/example-usage.js for other examples of functions available as part of this module.

System Architecture

Node version of stt-align by Chris Baume - R&D.

In pseudo code

• input, output as described in the example usage.

  • Accurate base text transcription, string.
  • Array of word objects transcription from STT service.

• Align words

  • normalize words, by removing capitalization and punctuation and converting numbers to letters

  • generate array list of words from base text, and array list of words from stt transcript.

    • get opcodes using difflib comparing two arrays
    • for equal matches, add matched STT word objects segment to results array base text index position.
    • Then iterate to result array to replace STT word objects text with words from base text

  • interpolate missing words

    • calculates missing timecodes
    • first optimization
      • using neighboring words to do a first pass at setting missing start and end time when present
    • Then Missing word timings are interpolated using interpolation library 'everpolate.

Development env

• node 10
• npm 6.1.0

Build

npm run build

bundles the code with react, into a ./build folder.

build demo

npm run build:demo

demo is in docs folder using github pages

Tests

npm run test:watch

• add more tests

Deployment

npm run publish:public