Adjust video brightness, contrast, saturation by API: eq filter

To change a clip's brightness, contrast or saturation by API, send an eq filter in the filtergraph field of Sume's video filter: eq=brightness=0.06:contrast=1.1:saturation=1.2. eq is on the filter allowlist, so the job returns a new MP4 and leaves the source alone. Check the string first with POST /v1/video-filter/check, which is free.

The option ranges below are from FFmpeg's eq entry, read 2026-10-02. The request shape and limits are from the video filter docs.

What are the eq options and their ranges?

FFmpeg's page gives: contrast -1000.0 to 1000.0, default 1; brightness -1.0 to 1.0, default 0; saturation 0.0 to 3.0, default 1; gamma 0.1 to 10, default 1. Small moves go a long way: start near brightness 0.05, contrast 1.1 and saturation 1.2, then compare stills.

How do I send it to Sume?

Required: video_url (a media.sume.com clip of 300 seconds or less) and a program: ops[], a filtergraph, or both. ops[] run first, then the graph. A filtergraph is filters only, up to 2,048 characters and 32 named filters, with no spaces inside a filter, no input or output labels, and no paths. Write options as name=key=value:key=value.

A filter name off the list fails as invalid_filtergraph with the allowed names in the message. Do not send vf or ffmpeg fields; those return ffmpeg_fields_rejected. The encode is $0.02 per job and the check is free.

curl -X POST https://api.sume.com/v1/video-filter/check \
  -H "Authorization: Bearer $SUME_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "video_url": "https://media.sume.com/artifacts/artf_demo/talk.mp4",
    "filtergraph": "eq=brightness=0.06:contrast=1.1:saturation=1.2"
  }'

What can the check not tell me?

It validates schema, allowlist and the source, and returns next_action submit_video_filter or fix_program_and_recheck. A program that passes can still fail on the worker, for example on a bad expression, and that returns as a structured job error. The check cannot say if the look is right; pull a still with video frames after the encode.