Script for combining the output of diart and whisper into a single Speaker-labelled SRT File

combine-whisper-diart.js

// Hrishi Olickel
// https://olickel.com
// 25 July 2023

const fs = require('fs');
const readline = require('readline');

const speakers = {}; // Hold start time and speaker
const speakerNames = ['Hrishi', 'Nick']; // Speaker names array

const rttmFilename = 'podcastPart1.rttm';
const srtFilename = 'podcastPart1.srt';
const outputSrtFilename = 'podcastPart1Annotated.srt';

const readRTTM = readline.createInterface({
    input: fs.createReadStream(rttmFilename),
    output: process.stdout,
    terminal: false
});

readRTTM.on('line', function(line) {
    console.log('Reading RTTM line: ', line);
    let lineParts = line.split(' ');
    let timeStart = parseFloat(lineParts[3]);
    let timeEnd = timeStart + parseFloat(lineParts[4]);
    let speaker = speakerNames[parseInt(lineParts[7].replace('speaker', ''))];
    speakers[timeStart.toFixed(3)] = speaker;
    console.log('Mapped speaker: ', speaker, ' to time start: ', timeStart.toFixed(3));
});

readRTTM.on('close', function() {
    console.log('Finished reading RTTM file');
    const readSRT = readline.createInterface({
        input: fs.createReadStream(srtFilename),
        output: process.stdout,
        terminal: false
    });

    let writeStream = fs.createWriteStream(outputSrtFilename);
    let currentSpeaker = '';

    readSRT.on('line', function(line) {
        console.log('Reading SRT line: ', line);
        let match = line.match(/(\d{2}:\d{2}:\d{2},\d{3}) --> (\d{2}:\d{2}:\d{2},\d{3})/);
        if (match) {
            let timeStart = timeToSeconds(match[1]);
            console.log('Matched SRT timestamp, time start: ', timeStart);
            currentSpeaker = findSpeaker(timeStart);
            console.log('Found speaker: ', currentSpeaker, ' for time start: ', timeStart);
        } else if (currentSpeaker && line.trim().length > 0) {
            console.log('Inserting speaker name into dialogue: ', currentSpeaker);
            line = `${currentSpeaker}: ${line}`;
            currentSpeaker = '';  
        }
        console.log('Writing line to merged file: ', line);
        writeStream.write(`${line}\n`);
    });

    readSRT.on('close', function() {
        console.log('Finished reading SRT file');
    });
});

function timeToSeconds(time) {
    let parts = time.split(':');
    console.log('Converting time to seconds: ', time);
    return parseFloat(parts[0]) * 3600 + parseFloat(parts[1]) * 60 + parseFloat(parts[2].replace(',', '.'));
}

function findSpeaker(timeStart) {
    console.log('Searching for speaker for time start: ', timeStart);
    let keys = Object.keys(speakers).map(k => parseFloat(k));
    for (let i = 0; i < keys.length; i++) {
        if (keys[i] > timeStart) {
            if (keys[i - 1] !== undefined) {
                console.log('Found speaker: ', speakers[keys[i - 1].toFixed(3)], ' for time start: ', timeStart);
                return speakers[keys[i - 1].toFixed(3)];
            }
        }
    }
    console.log('Speaker not found for time start: ', timeStart);
    return undefined;
}