Transcribe an audio file to text using Google Cloud Speech-to-Text API

android/quest/src/main/java/org/smartregister/fhircore/quest/ui/speechtoform/SpeechToText.kt

@@ -1,5 +1,57 @@
 package org.smartregister.fhircore.quest.ui.speechtoform
 
+import com.google.cloud.speech.v1.RecognitionAudio
+import com.google.cloud.speech.v1.RecognitionConfig
+import com.google.cloud.speech.v1.SpeechClient
+import com.google.cloud.speech.v1.SpeechRecognitionResult
+import com.google.cloud.speech.v1.RecognitionConfig.AudioEncoding
+import java.io.File
+import java.util.logging.Logger
+
 class SpeechToText {
 
+    private val logger = Logger.getLogger(SpeechToText::class.java.name)
+
+    /**
+     * Transcribes an audio file to text using Google Cloud Speech-to-Text API and writes it to a
+     * temporary file.
+     *
+     * @param audioFile The audio file to be transcribed.
+     * @return The temporary file containing the transcribed text.
+     */
+    fun transcribeAudioToText(audioFile: File): File? {
+        var tempFile: File? = null
+
+        SpeechClient.create().use { speechClient ->
+            val audioBytes = audioFile.readBytes()
+
+            // Build the recognition audio
+            val recognitionAudio = RecognitionAudio.newBuilder()
+                .setContent(com.google.protobuf.ByteString.copyFrom(audioBytes))
+                .build()
+
+            // Configure recognition settings
+            val config = RecognitionConfig.newBuilder()
+                .setEncoding(AudioEncoding.LINEAR16)
+                .setSampleRateHertz(16000)
+                .setLanguageCode("en-US")
+                .build()
+
+            // Perform transcription
+            val response = speechClient.recognize(config, recognitionAudio)
+            val transcription = response.resultsList.joinToString(" ") {
+                result: SpeechRecognitionResult ->
+                result.alternativesList[0].transcript
+            }
+
+            logger.info("Transcription: $transcription")
+
+            // Write transcription to a temporary file
+            tempFile = File.createTempFile("transcription", ".txt")
+            tempFile?.writeText(transcription)
+
+            logger.info("Transcription written to temporary file. ")
+        }
+        return tempFile
+    }
 }