Transcribe (Pre-recorded)

Transcribe an audio file. The model is chosen via `?model=`: - `?model=pulse-pro`: English-only, leaderboard-ranked accuracy. Raw bytes only; pass `webhook_url` to receive transcription asynchronously on long files. - `?model=pulse`: multilingual transcription (17 streaming + 26 pre-recorded languages), supports both raw bytes and audio-by-URL. ## When to use this Use this endpoint when you have a complete audio file (call recording, voicemail, podcast episode) and want the transcript back in one response. For live transcription as audio arrives, use the realtime WebSocket endpoint (`WS /waves/v1/stt/live`) instead. Pulse Pro has no streaming worker today; calls to `WS /waves/v1/stt/live?model=pulse-pro` return `400` before the WebSocket upgrades. ## Input methods - **Raw bytes**: `Content-Type: application/octet-stream` with the audio in the body. All knobs are query parameters. - **URL (`?model=pulse` only)**: `Content-Type: application/json` with `{"url": "..."}` in the body. ## Examples **cURL**: Pulse Pro, sync ```bash curl -X POST "https://api.smallest.ai/waves/v1/stt/?model=pulse-pro&language=en&word_timestamps=true" \ -H "Authorization: Bearer $SMALLEST_API_KEY" \ -H "Content-Type: application/octet-stream" \ --data-binary "@./call.wav" ``` **cURL**: Pulse Pro, async via webhook ```bash curl -X POST "https://api.smallest.ai/waves/v1/stt/?model=pulse-pro&language=en&webhook_url=https://your.app/cb" \ -H "Authorization: Bearer $SMALLEST_API_KEY" \ -H "Content-Type: application/octet-stream" \ --data-binary "@./call.wav" ``` Returns `200 { "status": "processing", "request_id": "..." }` immediately. The webhook receives the full transcription when ready. **cURL**: Pulse, audio-by-URL ```bash curl -X POST "https://api.smallest.ai/waves/v1/stt/?model=pulse&language=en" \ -H "Authorization: Bearer $SMALLEST_API_KEY" \ -H "Content-Type: application/json" \ -d '{"url": "https://your-bucket.s3.amazonaws.com/call.wav"}' ``` **Python** ```python import requests with open("./call.wav", "rb") as f: audio = f.read() r = requests.post( "https://api.smallest.ai/waves/v1/stt/", params={"model": "pulse-pro", "language": "en", "word_timestamps": "true"}, headers={"Authorization": f"Bearer {API_KEY}", "Content-Type": "application/octet-stream"}, data=audio, ) r.raise_for_status() print(r.json()["transcription"]) ``` **JavaScript / TypeScript** ```typescript import { readFileSync } from "node:fs"; const audio = readFileSync("./call.wav"); const params = new URLSearchParams({ model: "pulse-pro", language: "en", word_timestamps: "true" }); const res = await fetch(`https://api.smallest.ai/waves/v1/stt/?${params}`, { method: "POST", headers: { Authorization: `Bearer ${process.env.SMALLEST_API_KEY}`, "Content-Type": "application/octet-stream" }, body: audio, }); console.log((await res.json()).transcription); ``` ## Common gotchas - **`model` is required.** Missing or invalid values return `400` with an enum-validation error. - **Pulse Pro is English only.** Pass `language=en`. Other language codes are accepted at the wire level but produce unpredictable output. - **Pulse Pro does not support audio-by-URL.** Send raw bytes or use `?model=pulse` for the URL flow. - **Async (webhook) mode is Pulse Pro only.** Pulse runs sync only on this endpoint. - **Max payload 250 MB.** Larger requests return `413`. Compress to mono 16 kHz PCM if you are close to the limit; quality is unaffected.