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Please provide as much information as possible. At least, this should include a description of your issue and steps to reproduce the problem. If possible please provide a summary of what steps or workarounds you have already tried, and any docs or articles you found (un)helpful.

Problem you have encountered:  Currently I am using streamingRecognize and getting a latency of 2seconds and above.


What you expected to happen: Is there any way to tune down the latency below 1seocnds?


Steps to reproduce:


Other information (workarounds you have tried, documentation consulted, etc): I have tried to implement the best practices mentioned in the docs, but it did not work.


Currently I am getting the audio from the browser using mediaRecorder and sending the audio file to the server using socket. I am provide the code I am using on the server end.

Any kind of help or insights will be appreciated. Thank you.

Code:
*server.js*
import express from 'express';
import ViteExpress from 'vite-express';
import { Server } from 'socket.io';
import http from 'http';
import { Readable } from 'stream';
import gcpSTTService from './services/gcpSTTService.js';

const app = express();

const server = http.createServer(app);
const io = new Server(server);

io.on('connection', (socket) => {
        console.log('a user connected');

        // Create a Readable stream to handle audio data
        const audioStream = new Readable({
                read(size) {
                        // Do nothing here since we'll be pushing data from the socket event handler
                },
        });

        // Handle incoming audio data from the client
        socket.on('gcpSpeechToText', async (data) => {
                console.log('Received audio data');

                let audioBuffer;

                if (typeof data === 'string') {
                        // Convert string to Buffer
                        audioBuffer = Buffer.from(data, 'base64');
                } else if (Buffer.isBuffer(data) || data instanceof Uint8Array) {
                        // Data is already a Buffer or Uint8Array
                        audioBuffer = data;
                } else {
                        // Handle other data types or throw an error
                        console.error('Unsupported data type received:', typeof data);
                        return;
                }

                // Push the audio data into the stream
                audioStream.push(audioBuffer);
        });

        // Pipe the audio stream to the test function

        audioStream.pipe(gcpSTTService(io));

        socket.on('disconnect', () => {
                console.log('User disconnected');
        });
});

server.listen(3000, () => console.log('Server is listening...'));

ViteExpress.bind(app, server);


*gcpSTTService.js*
import speech from '@google-cloud/speech';
const client = new speech.SpeechClient();
// import { io } from "socket.io-client";

function gcpSTTService(io) {
        const config = {
                encoding: 'WEBM_OPUS',
                sampleRateHertz: 48000,
                languageCode: 'en-US',
        };

        const request = {
                config: config,
                interimResults: false, // If you want interim results, set this to true
        };

        return client
                .streamingRecognize(request)
                .on('error', console.error)
                .on('data', (data) => {
                        // Check if interim results are available
                        if (data.results[0] && data.results[0].alternatives[0]) {
                                console.log(
                                        `Interim Transcription: ${data.results[0].alternatives[0].transcript}`
                                );
                                io.emit(
                                        'gcpSpeechToTextResult',
                                        data.results[0].alternatives[0].transcript
                                );
                                return data.results[0].alternatives[0].transcript;
                        }
                });
}

export default gcpSTTService;