ovos_tips.md

STT - tips and tricks

Saving Transcriptions

You can enable saving of recordings to file, this should be your first step to diagnose problems, is the audio inteligible? is it being cropped? too noisy? low volume?

set "save_utterances": true in your listener config, recordings will be saved to ~/.local/share/mycroft/listener/utterances

If the recorded audio looks good to you, maybe you need to use a different STT plugin, maybe the one you are using does not like your microphone, or just isn't very good for your language

Wrong Transcriptions

If you consistently get specific words or utterances transcribed wrong, you can remedy around this to some extent by using the ovos-utterance-corrections-plugin

You can define replacements at word level ~/.local/share/mycroft/word_corrections.json

for example whisper STT often gets artist names wrong, this allows you to correct them

{
    "Jimmy Hendricks": "Jimi Hendrix",
    "Eric Klapptern": "Eric Clapton",
    "Eric Klappton": "Eric Clapton"
}

Silence Removal

By default OVOS applies VAD (Voice Activity Detection) to crop silence from the audio sent to STT, this helps in performance and in accuracy (reduces hallucinations in plugins like FasterWhisper)

Depending on your microphone/VAD plugin, this might be removing too much audio

set "remove_silence": false in your listener config, this will send the full audio recording to STT

Listen Sound

does your listen sound contain speech? some users replace the "ding" sound with words such as "yes?"

In this case the listen sound will be sent to STT and might negatively affect the transcription

set "instant_listen": false in your listener config, this will drop the listen sound audio from the STT audio buffer. You will need to wait for the listen sound to finish before speaking your command in this case