Workflow Subtitles Accessibility

IF captions embedded in source stream (CEA-608/708):
  → MediaLive extracts and passes through or converts
IF captions in sidecar file (SRT, VTT, TTML):
  → MediaConvert (VOD): attach as input sidecar
  → MediaLive (live): not supported as sidecar input
IF no captions exist and auto-captioning needed:
  → Amazon Transcribe (real-time for live, batch for VOD)
  → CONSTRAINT: adds 5-10s latency for live
IF burn-in (open captions) required:
  → MediaLive or MediaConvert burn-in output setting
  → CONSTRAINT: cannot be turned off by viewer

IF source has embedded CEA-608/708:
  → Pass through in MediaLive (default behavior)
  → Convert to WebVTT sidecar in MediaPackage for HLS/DASH
IF using Amazon Transcribe for live auto-captioning:
  → Transcribe real-time streaming → MediaLive caption input
  → Adds 5-10s latency
IF burn-in required (regulatory, accessibility):
  → Enable burn-in in MediaLive output settings
  → Choose font, size, position, background

IF delivering HLS:
  → WebVTT sidecar (preferred) or embedded CEA-608
IF delivering DASH:
  → TTML or WebVTT sidecar
IF delivering CMAF:
  → WebVTT (works for both HLS and DASH manifests)
IF burn-in needed:
  → MediaConvert burn-in settings per output

IF FCC compliance (US broadcast):
  → CEA-608/708 passthrough required
  → Maintain caption timing accuracy
IF CVAA compliance (US internet video):
  → Closed captions must be available on all platforms
  → User must be able to customize appearance (font, size, color)
  → WebVTT with player-side rendering (not burn-in)
IF EU/EAA compliance:
  → Audio description track required
  → Multi-language subtitles