AWS Transcribe support

index.js

@@ -33,6 +33,11 @@ const argv = require("yargs/yargs")(process.argv.slice(2))
 			type: "number",
 			group: "Server",
 		},
+		provider: {
+			desc: "Speech-to-text provider",
+			default: "google",
+			type: "string",
+		},
 	})
 	.strict()
 	.argv;
@@ -46,7 +51,7 @@ server.on("connection", (client) => {
 		codecs: codecs,
 		languages: languages,
 		transport: client,
-		provider: getProvider("google", argv),
+		provider: getProvider(argv.provider, argv),
 	});
 });
 

lib/provider.js

@@ -15,8 +15,16 @@
  *  limitations under the License.
  */
 
-const { Writable } = require('stream');
-const speech = require('@google-cloud/speech');
+const {
+	Writable,
+} = require('stream');
+const GoogleSpeech = require('@google-cloud/speech');
+const {
+	TranscribeStreamingClient,
+	StartStreamTranscriptionCommand,
+} = require('@aws-sdk/client-transcribe-streaming');
+const fs = require('fs');
+const { WaveFile } = require('wavefile');
 
 /*
  * For speech provider implementer.
@@ -114,7 +122,7 @@ class GoogleProvider extends Writable {
 	}
 
 	_construct(callback) {
-		this.client = new speech.SpeechClient();
+		this.client = new GoogleSpeech.SpeechClient();
 
 		callback();
 	}
@@ -252,23 +260,159 @@ class GoogleProvider extends Writable {
 		if (!this.recognizeStream) {
 			return;
 		}
+	}
+}
+
+class AWSProvider extends Writable {
+	constructor(options) {
+		super();
 
-		this.cork(); // Buffer any incoming data
+		this.LanguageCode = "en-GB";
+		this.MediaEncoding = "pcm";
+		this.credentials = {
+			accessKeyId: process.env.AWS_ACCESS_KEY_ID,
+			secretAccessKey: process.env.AWS_SECRET_ACCESS_KEY,
+		}
+
+		console.debug(process.env.AWS_SECRET_KEY_ID)
+
+		this.stream = new TransformStream({ highWaterMark: 1 * 1024 });
+		this.readStream = this.stream.readable.getReader({ highWaterMark: 1 * 1024 });
+		this.writeStream = this.stream.writable;
 
-		this.recognizeStream.end();
 		this.recognizeStream = null;
+
+		this.fullStream = [];
+
+		console.log(this.writeStream);
 	}
 
-	/**
-	 * Restarts the recognition stream.
-	 *
-	 * @param {Object} [config] - configuration to use
-	 * @param {Object} [config.codec] - the codec to map to an encoding
-	 * @param {string} [config.language] - the language to use
-	 */
-	restart(config) {
+	_construct(callback) {
+		this.client = new TranscribeStreamingClient({
+			region: "eu-west-2",
+			credentials: this.credentials
+		});
+
+		callback();
+	}
+
+	_write(chunk, encoding, callback) {
+		this.fullStream.push(chunk);
+
+		const wav = new WaveFile();
+
+		wav.fromScratch(1, 8000, '8m', chunk);
+		wav.fromMuLaw();
+
+		wav.toSampleRate(16000);
+
+		this.recognizeStream.write(wav.data.samples);
+
+		callback();
+	}
+
+	_writev(chunks, callback) {
+		for (let chunk in chunks) {
+			this._write(chunk, null, callback);
+		}
+
+		callback();
+	}
+
+	_final(callback) {
 		this.stop();
-		this.start(config);
+
+		callback();
+	}
+
+	start(config) {
+		// this.setConfig(config);
+		// config = this.config;
+
+		console.log("START");
+
+		this.recognizeStream = this.writeStream.getWriter();
+
+		// const passthrough = new PassThrough();
+		// this.readStream.pipe(passthrough);
+
+		const readStream = this.readStream;
+
+		async function* audioSource() {
+			// await readStream.start();
+			while (readStream.ends !== true) {
+				const chunk = await readStream.read();
+				yield chunk;
+			}
+		}
+
+		async function* audioStream() {
+			for await (const chunk of audioSource()) {
+				yield {AudioEvent: {AudioChunk: chunk.value}};
+			}
+		}
+
+		this.param = {
+			LanguageCode: this.LanguageCode,
+			MediaEncoding: this.MediaEncoding,
+			MediaSampleRateHertz: 16000,
+			AudioStream: audioStream(),
+		}
+
+		this.command = new StartStreamTranscriptionCommand(this.param);
+
+		this.client.send(this.command).then(async (res) => {
+			for await (const event of res.TranscriptResultStream) {
+				if (event.TranscriptEvent) {
+					const results = event.TranscriptEvent.Transcript.Results;
+					if(results[0] !== undefined) {
+						if(!results[0].IsPartial) {
+							console.debug("AWSProvider: result: " + results[0].Alternatives[0].Transcript);
+							const result = {
+								"text": results[0].Alternatives[0].Transcript
+							};
+
+							this.emit('result', result);
+						}
+					}
+
+					// Print all the possible transcripts
+				}
+			};
+		}).catch((err) => {
+			console.debug(err);
+		})
+		return;
+	}
+
+	stop() {
+		if(!this.recognizeStream) {
+			return;
+		}
+
+
+		const buffer = Buffer.concat(this.fullStream);
+		console.debug(buffer);
+
+		const wav = new WaveFile();
+
+		wav.fromScratch(1, 8000, '8m', buffer);
+		wav.fromMuLaw();
+
+		wav.toSampleRate(16000);
+
+		fs.writeFileSync('stream.wav', wav.toBuffer());
+
+		// this.recognizeStream.close();
+
+		console.log("End of stream");
+
+		// return;
+	}
+
+	restart(config) {
+		this.stop()
+		this.start(config)
 	}
 }
 
@@ -284,6 +428,10 @@ function getProvider(name, options) {
 		return new GoogleProvider(options);
 	}
 
+	if (name == "aws") {
+		return new AWSProvider(options);
+	}
+
 	throw new Error("Unsupported speech provider '" + name + "'");
 }