This project demonstrates how use ffmpeg to convert .ogg files (Vorbis and Opus) to the right format for Speech-to-Text transcription using the Microsoft Cognitive Services Speech Service. This could be used to transcribe voice messages encoded using the Opus (https://en.wikipedia.org/wiki/Opus_(audio_format)) codec or other codecs using the .ogg container format.
One use for this project is the transcription of WhatsApp voice messages received through the WhatsApp Business API
To make this sample work, you need the Cognitive Services Speech Service Java SDK which has been already added to the pom file.
public final static String MS_SPEECH_KEY = "your-microsoft-speech-key";
public final static String MS_SPEECH_REGION = "westeurope";
public final static String MS_SPEECH_RECOGNITION_LANG = "de-de";You also need to download ffmpeg which is used for transcoding and set the right path to it in the source. An audio file can be read from disk or passed as a byte array. It will then, in memory, be transcoded to wav / pcm format for transcription using the Cognitive Services Speech Service.
Also check out the Microsoft Speech SDK Sample Repository to learn more and use more of it's functionality.
Thank you @chgeuer for your contributions.