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Audio

Speech-to-text and text-to-speech engines — local Whisper, OpenAI, Azure, Deepgram, Mistral and ElevenLabs — and voice mode.

These variables are set on the Hrida.ai container. Variables marked ConfigVar are saved to the database on first start — see how ConfigVar works before changing them later.

BYPASS_PYDUB_PREPROCESSING​

  • Type: bool
  • Default: False
  • Description: When enabled, skips pydub-based preprocessing (format conversion to MP3, compression, and chunked splitting by size) before audio is sent to the Speech-to-Text engine. Useful when the upstream provider already handles these steps, when ffmpeg is unavailable on the host, or when you want to pass audio through untouched. Applies to all STT engines.

Whisper Speech-to-Text (Local)​

WHISPER_MODEL​

  • Type: str
  • Default: base
  • Description: Sets the Whisper model to use for Speech-to-Text. The backend used is faster_whisper with quantization to int8.
  • Persistence: This environment variable is a ConfigVar variable.

WHISPER_MODEL_DIR​

  • Type: str
  • Default: ${DATA_DIR}/cache/whisper/models
  • Description: Specifies the directory to store Whisper model files.

WHISPER_COMPUTE_TYPE​

  • Type: str
  • Default: int8 (CPU), float16 (CUDA)
  • Description: Sets the compute type for Whisper model inference. Defaults to int8 for CPU and float16 for CUDA (with fallback to int8/int8_float16).

WHISPER_VAD_FILTER​

  • Type: bool
  • Default: False
  • Description: Specifies whether to apply a Voice Activity Detection (VAD) filter to Whisper Speech-to-Text.

WHISPER_MODEL_AUTO_UPDATE​

  • Type: bool
  • Default: False
  • Description: Toggles automatic update of the Whisper model.

WHISPER_LANGUAGE​

  • Type: str
  • Default: None
  • Description: Specifies the ISO 639-1 language Whisper uses for STT (ISO 639-2 for Hawaiian and Cantonese). Whisper predicts the language by default.

WHISPER_MULTILINGUAL​

  • Type: bool
  • Default: False
  • Description: Toggles whether to use the multilingual Whisper model. When set to False, the system will use the English-only model for better performance in English-centric tasks. When True, it supports multiple languages.

Speech-to-Text (OpenAI)​

AUDIO_STT_ENGINE​

  • Type: str
  • Options:
    • "" (empty string) - Uses the built-in local Whisper engine for Speech-to-Text. This runs Whisper on the backend server.
    • openai - Uses an OpenAI-compatible API for Speech-to-Text.
    • deepgram - Uses Deepgram engine for Speech-to-Text.
    • azure - Uses Azure Cognitive Services for Speech-to-Text.
    • mistral - Uses Mistral API for Speech-to-Text.
  • Description: Specifies the Speech-to-Text engine to use. When left as an empty string (the default), the backend runs a local Whisper instance. Note: The "Web API" option seen in User Settings is a frontend-only setting that uses the browser's built-in speech recognition and does not call this backend endpoint at all.
  • Persistence: This environment variable is a ConfigVar variable.

AUDIO_STT_MODEL​

  • Type: str
  • Default: whisper-1
  • Description: Specifies the Speech-to-Text model to use for OpenAI-compatible endpoints.
  • Persistence: This environment variable is a ConfigVar variable.

AUDIO_STT_OPENAI_API_BASE_URL​

  • Type: str
  • Default: ${OPENAI_API_BASE_URL}
  • Description: Sets the OpenAI-compatible base URL to use for Speech-to-Text.
  • Persistence: This environment variable is a ConfigVar variable.

AUDIO_STT_OPENAI_API_KEY​

  • Type: str
  • Default: ${OPENAI_API_KEY}
  • Description: Sets the OpenAI API key to use for Speech-to-Text.
  • Persistence: This environment variable is a ConfigVar variable.

Speech-to-Text (Azure)​

AUDIO_STT_AZURE_API_KEY​

  • Type: str
  • Default: None
  • Description: Specifies the Azure API key to use for Speech-to-Text.
  • Persistence: This environment variable is a ConfigVar variable.

AUDIO_STT_AZURE_REGION​

  • Type: str
  • Default: None
  • Description: Specifies the Azure region to use for Speech-to-Text.
  • Persistence: This environment variable is a ConfigVar variable.

AUDIO_STT_AZURE_LOCALES​

  • Type: str
  • Default: None
  • Description: Specifies the locales to use for Azure Speech-to-Text.
  • Persistence: This environment variable is a ConfigVar variable.

AUDIO_STT_AZURE_BASE_URL​

  • Type: str
  • Default: None
  • Description: Specifies a custom Azure base URL for Speech-to-Text. Use this if you have a custom Azure endpoint.
  • Persistence: This environment variable is a ConfigVar variable.

AUDIO_STT_AZURE_MAX_SPEAKERS​

  • Type: int
  • Default: 3
  • Description: Sets the maximum number of speakers for Azure Speech-to-Text diarization.
  • Persistence: This environment variable is a ConfigVar variable.

Speech-to-Text (Deepgram)​

DEEPGRAM_API_KEY​

  • Type: str
  • Default: None
  • Description: Specifies the Deepgram API key to use for Speech-to-Text.
  • Persistence: This environment variable is a ConfigVar variable.

Speech-to-Text (Mistral)​

AUDIO_STT_MISTRAL_API_KEY​

  • Type: str
  • Default: None
  • Description: Specifies the Mistral API key to use for Speech-to-Text.
  • Persistence: This environment variable is a ConfigVar variable.

AUDIO_STT_MISTRAL_API_BASE_URL​

  • Type: str
  • Default: https://api.mistral.ai/v1
  • Description: Specifies the Mistral API base URL to use for Speech-to-Text.
  • Persistence: This environment variable is a ConfigVar variable.

AUDIO_STT_MISTRAL_USE_CHAT_COMPLETIONS​

  • Type: bool
  • Default: False
  • Description: When enabled, uses the chat completions endpoint for Mistral Speech-to-Text instead of the dedicated transcription endpoint.
  • Persistence: This environment variable is a ConfigVar variable.

Speech-to-Text (General)​

AUDIO_STT_SUPPORTED_CONTENT_TYPES​

  • Type: str
  • Default: None
  • Description: Comma-separated list of supported audio MIME types for Speech-to-Text (e.g., audio/wav,audio/mpeg,video/*). Leave empty to use defaults.
  • Persistence: This environment variable is a ConfigVar variable.

AUDIO_STT_ALLOWED_EXTENSIONS​

  • Type: str
  • Default: mp3,wav,m4a,webm,ogg,flac,mp4,mpga,mpeg
  • Description: Comma-separated list of audio file extensions accepted by the Speech-to-Text upload endpoint. Uploads with extensions outside this list are rejected with 400 Invalid audio file extension. Comparison is case-insensitive. Set to an empty value to skip the extension check (MIME-type validation via AUDIO_STT_SUPPORTED_CONTENT_TYPES still applies). Configurable via Admin Settings → Audio → STT.
  • Persistence: This environment variable is a ConfigVar variable.

Text-to-Speech​

AUDIO_TTS_API_KEY​

  • Type: str
  • Description: Sets the API key for Text-to-Speech.
  • Persistence: This environment variable is a ConfigVar variable.

AUDIO_TTS_ENGINE​

  • Type: str
  • Options:
    • "" (empty string) - Disables backend TTS. When empty, TTS requests do not reach the backend. All TTS is handled client-side using the browser's Web Speech API or the user-configurable "Browser Kokoro" option in User Settings.
    • openai - Uses an OpenAI-compatible API for Text-to-Speech.
    • mistral - Uses Mistral's Text-to-Speech API.
    • elevenlabs - Uses ElevenLabs engine for Text-to-Speech.
    • azure - Uses Azure Cognitive Services for Text-to-Speech.
    • transformers - Uses a local SentenceTransformers-based model for Text-to-Speech (runs on the backend).
  • Description: Specifies the Text-to-Speech engine to use on the backend. When left as an empty string (the default), no backend TTS service is configured, and audio playback relies entirely on the user's browser capabilities or frontend options like "Browser Kokoro".
  • Persistence: This environment variable is a ConfigVar variable.

AUDIO_TTS_MODEL​

  • Type: str
  • Default: tts-1
  • Description: Specifies the OpenAI text-to-speech model to use.
  • Persistence: This environment variable is a ConfigVar variable.

AUDIO_TTS_VOICE​

  • Type: str
  • Default: alloy
  • Description: Sets the OpenAI text-to-speech voice to use.
  • Persistence: This environment variable is a ConfigVar variable.

AUDIO_TTS_SPLIT_ON​

  • Type: str
  • Default: punctuation
  • Description: Sets the OpenAI text-to-speech split on to use.
  • Persistence: This environment variable is a ConfigVar variable.

Azure Text-to-Speech​

AUDIO_TTS_AZURE_SPEECH_REGION​

  • Type: str
  • Description: Sets the region for Azure Text to Speech.
  • Persistence: This environment variable is a ConfigVar variable.

AUDIO_TTS_AZURE_SPEECH_OUTPUT_FORMAT​

  • Type: str
  • Default: audio-24khz-160kbitrate-mono-mp3
  • Description: Sets the output format for Azure Text to Speech.
  • Persistence: This environment variable is a ConfigVar variable.

AUDIO_TTS_AZURE_SPEECH_BASE_URL​

  • Type: str
  • Default: None
  • Description: Specifies a custom Azure Speech base URL for Text-to-Speech. Use this if you have a custom Azure endpoint.
  • Persistence: This environment variable is a ConfigVar variable.

Voice Mode​

ENABLE_VOICE_MODE_PROMPT​

  • Type: bool
  • Default: True
  • Description: Master switch for the voice-mode system prompt. When True, voice-mode chats prepend either the custom VOICE_MODE_PROMPT_TEMPLATE (if set) or DEFAULT_VOICE_MODE_PROMPT_TEMPLATE. When False, no voice-specific system prompt is injected — the model uses only the regular system prompt and chat history. Configurable in Admin Settings → Interface → Voice Mode Custom Prompt (toggle).
  • Persistence: This environment variable is a ConfigVar variable. Stored at config key task.voice.prompt.enable.

VOICE_MODE_PROMPT_TEMPLATE​

  • Type: str
  • Default: The value of DEFAULT_VOICE_MODE_PROMPT_TEMPLATE environment variable.
  • Description: Configures a custom system prompt for voice mode interactions. Allows administrators to control how the AI responds in voice conversations (style, length, tone). Leave empty to use the default prompt optimized for voice conversations, or provide custom instructions to tailor the voice assistant's behavior. Only applied when ENABLE_VOICE_MODE_PROMPT is True.
  • Persistence: This environment variable is a ConfigVar variable.

OpenAI Text-to-Speech​

AUDIO_TTS_OPENAI_API_BASE_URL​

  • Type: str
  • Default: ${OPENAI_API_BASE_URL}
  • Description: Sets the OpenAI-compatible base URL to use for text-to-speech.
  • Persistence: This environment variable is a ConfigVar variable.

AUDIO_TTS_OPENAI_API_KEY​

  • Type: str
  • Default: ${OPENAI_API_KEY}
  • Description: Sets the API key to use for text-to-speech.
  • Persistence: This environment variable is a ConfigVar variable.

AUDIO_TTS_OPENAI_PARAMS​

  • Type: str (JSON)
  • Default: {}
  • Description: Additional parameters for OpenAI-compatible TTS API in JSON format. Allows customization of API-specific settings.
  • Example: {"speed": 1.0}
  • Persistence: This environment variable is a ConfigVar variable.

Mistral Text-to-Speech​

AUDIO_TTS_MISTRAL_API_KEY​

  • Type: str
  • Default: None
  • Description: Sets the API key used for Mistral Text-to-Speech.
  • Persistence: This environment variable is a ConfigVar variable.

AUDIO_TTS_MISTRAL_API_BASE_URL​

  • Type: str
  • Default: https://api.mistral.ai/v1
  • Description: Sets the base URL used for Mistral Text-to-Speech.
  • Persistence: This environment variable is a ConfigVar variable.
info

When AUDIO_TTS_ENGINE=mistral, Hrida.ai uses mistral-tts-latest when AUDIO_TTS_MODEL is empty.

Elevenlabs Text-to-Speech​

ELEVENLABS_API_BASE_URL​

  • Type: str
  • Default: https://api.elevenlabs.io
  • Description: Configures custom ElevenLabs API endpoints, enabling support for EU residency API requirements and other regional deployments.
  • Persistence: This environment variable is a ConfigVar variable.
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