Dim busy b-roll so captions read: video filter, then captions, $0.22

Bright, busy footage makes captions hard to read, and the cheapest fix on Sume is to dim the clip before you burn them: video-filter with dim at 0.45 costs $0.02 and a standalone caption job costs $0.20, so $0.22 per clip and $2.20 for ten.

The order matters

Dim first, caption second. The captions run on the filtered MP4, so the white text sits on a darker background and is not itself dimmed. amount is in (0, 1]: 1 changes nothing, and 0.45 reduces the brightness a lot. POST /v1/video-filter/check validates the program for free and returns next_action.

Requests

Submit the filter job, wait for the result, then send the result's video_url to captions.

curl -X POST https://api.sume.com/v1/video-filter \
  -H "Authorization: Bearer $SUME_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: dim-clip-07" \
  -d '{
    "video_url": "https://media.sume.com/artifacts/artf_demo/broll.mp4",
    "ops": [{ "op": "dim", "amount": 0.45 }]
  }'

# then, with the dimmed clip:
curl -X POST https://api.sume.com/v1/video-captions \
  -H "Authorization: Bearer $SUME_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: caption-clip-07" \
  -d '{ "video_url": "https://media.sume.com/artifacts/artf_demo/dimmed.mp4", "style": "slam" }'

Limits and gotchas

• The filter source is limited to 300 seconds.
• Captions need audible speech. For a silent clip send cues with text, start and end instead.
• Korean text on slam, punch or tiktok-green is rejected (caption_hangul_text_latin_style); use a Hangul style.
• dim multiplies luma only: black stays black.