Stt-align-node

See The alignment problem in the docs for more background of the problem this module set out to address.

Originally developed as a node version of python's stt-align by Chris Baume - BBC R&D.

Setup - development

git clone [email protected]:bbc/stt-align-node.git

cd stt-align-node

npm install

Setup - in production

npm install @bbc/stt-align-node

Usage

Other then to realign STT results with accurate text, this modules can also be used to perform related oprations in the same domain, such as benchmarking STT.

|Function| Description | type| |:------|------|----| |alignSTT|Realign STT json with accurate text. by transposing words from accurate text to timecodes of STT. | json| |diffsList|return a diff json of STT vs accurate text | json| |diffsListAsHtml|return a diff of STT vs accurate text as HTML| html| |diffsCount|return a diff of STT vs accurate text as HTML| json| |calculateWordDuration|return a diff of STT vs accurate text as HTML| Number|

See See README in example-usage folder as well as code examples for more.

System Architecture

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

In pseudo code overview of alignSTT:

• 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

Publish demo to github pages

npm run deploy:ghpages

Tests

npm run test:watch

• [ ] add more tests

Deployment

Deploy to npm

npm run publish:public