Files

Speech-to-Text worker — Whisper (RunPod Serverless)

Multilingual voice-to-text via faster-whisper — lets a worker speak instead of typing annotation text, in both the image and video editors. 99 languages incl. Hindi/regional + English. Chosen over Parakeet/NeMo because it has no heavy dependencies (no NeMo, no torch), so it builds cleanly.

Contract

Request → POST /runsync:

{ "input": { "audio": "<base64 audio>", "language": "en", "timestamps": false } }
  • audio: base64 wav/mp3/m4a (any sample rate — resampled internally)
  • language: optional (e.g. "hi", "en"); omit to auto-detect
  • timestamps: optional — per-segment start/end

Response → { "output": { "transcript": "...", "language": "en" } } (with segments: [{text, start_sec, end_sec}] if timestamps: true), or { "output": { "error": "..." } }.

Deploy (new endpoint — one per model)

  1. RunPod → Serverless → New Endpoint → Deploy from a GitHub repositorySumit-Pluto/photo_gallery.
  2. Dockerfile path: /workers/voice-to-text/Dockerfile
  3. Config:
    • GPU: light — 16 GB (T4 / A4000) is plenty (large-v3 ≈ 5 GB VRAM).
    • Network volume: attach your weights volume (caches the model).
    • Workers: Max 1, Active 0, FlashBoot on. Execution timeout ~300s (first-run download).
  4. Warm up once (downloads the model, ~1.5 GB):
    curl -X POST https://api.runpod.ai/v2/<NEW_ID>/runsync \
      -H "Content-Type: application/json" -H "Authorization: Bearer <API_KEY>" \
      -d '{"input":{"audio":"<base64-wav>","language":"en"}}'
    
  5. In Vercel, set RUNPOD_STT_URL = https://api.runpod.ai/v2/<NEW_ID>/runsync (server-only).

Tuning (env vars)

Var Default Purpose
WHISPER_MODEL large-v3 accuracy vs speed — medium / small are faster/lighter
WHISPER_COMPUTE float16 int8_float16 uses less VRAM

App integration (next step, not yet built)

Mic-record button in the editor's text/annotation tool → /api/ai/transcribe (proxies here) → inserts the transcript. Client rpTranscribe() already exists in apps/web/src/lib/runpod/endpoints.ts.