Add a 3-second end card after a clip with Timeline 1.0

An end card is a still shown after the last shot, usually with a logo and a line of text. In Timeline 1.0 a still is a valid video[] source and is held as a static image, so the card is a second slot placed after the clip. Give that slot a fade transition and set a soundtrack with a fade_out_seconds so the music ends on the card instead of cutting off.

How do I make the card image?

Design it anywhere and put it in your workspace as a media.sume.com file, or generate one with POST /v1/images; see the Images docs for sizes and aspect ratios. Then match the card's shape to the render: a 1080x1920 default output wants a vertical card, and fit: "cover" crops anything else.

Which fields shape the ending?

What does the request look like?

This is an 8-second clip followed by a 3-second card, so audio.duration_seconds is 11 and the card starts at 8. The spine here is silent and the music is a soundtrack; a clip's own audio is not carried through a render, so detach it with Audio detach if you need to keep it. Declared starts are authoritative and the compiler compensates for the fade overlap.

curl -X POST https://api.sume.com/v1/timeline-1.0/render \
  -H "Authorization: Bearer $SUME_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: end-card-001" \
  -d '{
    "audio": { "mode": "silence", "duration_seconds": 11 },
    "soundtrack": {
      "url": "https://media.sume.com/artifacts/artf_demo/bed.mp3",
      "loop": true,
      "fade_out_seconds": 3
    },
    "video": [
      { "source_url": "https://media.sume.com/artifacts/artf_demo/spot.mp4",
        "start": 0, "duration": 8 },
      { "source_url": "https://media.sume.com/artifacts/artf_demo/end-card.png",
        "start": 8, "duration": 3,
        "transition": { "type": "fade", "duration": 0.5 } }
    ]
  }'

What does it cost?

The render is billed at $0.10 per output minute, and an 11-second output rounds up to one minute. The card adds no inference cost, since the docs describe Timeline as worker ffmpeg only. To append the same card to many clips, change only the first source_url and the idempotency key and send one request per clip.