Seedance 1.5 Pro API

Introduction

Seedance 1.5 Pro image-to-video starts the clip on a picture you supply and animates it for up to 12 seconds. With camera_fixed set, the supplied framing stays exactly as composed, which is why this endpoint produces usable plates.

ByteDance Seedance 1.5 Pro publishes two endpoints, text-to-video and image-to-video. Both return 4 to 12 second clips at 480p, 720p or 1080p with native audio, and both carry a camera_fixed switch.

Choose a Seedance 1.5 Pro mode by starting material

Key features

camera_fixed holds the frame

Left false, the default, the model invents its own moves: a drift, a push, a slow orbit. Set it to true and the camera stops while the subject keeps moving inside the frame. A locked frame can be tracked, keyed, composited or looped, and neither Seedance 2.0 nor 2.5 offers this switch.

Sound in the same pass

generate_audio defaults to true and renders ambience, movement effects and voice locked to the frames. It moves the request into a higher rate tier, so turn it off for product loops and for plates that will be scored later.

A clear ceiling

Clips run 4 to 12 whole seconds at 480p, 720p or 1080p, in six fixed aspect ratios with 16:9 as the default and no adaptive option. There is no reference endpoint; seed is available at 480p and 720p. Jobs that need 4K, longer takes or a multi-image cast belong on Seedance 2.0 or 2.5; what 1.5 Pro keeps is the camera lock.

Request parameters

Pricing

Prices are in credits, the same credits you use on the website (1 credit = $0.01). The hold is taken when the task is accepted and settled to the actual charge when it finishes; failed tasks are refunded.

Each task is rounded up to whole credits, so one run at the lowest tier costs 9 credits for a 5-second clip ($0.09).

For an exact number before you run, send the same body to POST /jobs/quote.

Use cases

Plates for compositing

Send a still you have already approved, set camera_fixed, and the composition holds for the whole clip while only the subject moves. The result behaves like tripod footage: a clean background to key against, a stable surface to track a title onto, a plate an editor can cut into a real sequence.

Product turntables and loops

A fixed frame with a rotating object is the classic case: nothing drifts, the horizon stays level, and the last frame lands close enough to the first to loop. Turn generate_audio off, because a product loop almost never wants room tone.

Slow environmental motion

The published example layers falling snow, rolling steam and water over a single still, with a very slow push-in so none of it is hidden by camera speed. Weather, smoke and water are the kind of motion a held composition shows off best.

Prompt guide & pro tips

Send both required fields

prompt and image_url are both required here, and the prompt needs at least 3 characters. The image must be a public, directly downloadable JPEG, PNG or WebP under 10 MB. Text, watermarks and logos in the still travel into the video, so clean them off first.

Match the aspect ratio to the still

There is no adaptive option, and aspect_ratio defaults to 16:9. When the requested ratio differs from the source, the frame is reframed and the subject can lose its margins, so pick the ratio that matches your still.

Adapt the included example

The published example uses aspect_ratio 16:9, duration_seconds 5 and resolution 720p, with the audio default left on.

The frame supplies the lanterns and the setting; the prompt only lowers her into the spring and lets her breathe out. Keep that split when you swap in your own still.

Keep motion inside a locked frame

With camera_fixed set to true, describe only movement that happens within the frame, because a camera instruction and a locked camera pull against each other. Confirm the motion at 4 or 5 seconds before extending to 12, since a longer shot drifts further from its source frame.

API quick start

Call the Seedance 1.5 Pro API in three steps

1. Create an API key. Sign in to PopNow and create a key in the API console. Keys start with sk-popnow- and use the same credits as the website.
2. Send the request. POST /jobs/createTask with model bytedance/seedance-1.5-pro/image-to-video and an input object that follows the parameter table. The response returns a task ID straight away.
3. Get the result. Poll GET /jobs/recordInfo with the task ID, or pass a callBackUrl and we post the result to it. Download the output links when the task succeeds.

# 1. Create the task. Keep the Idempotency-Key if you retry after a network error.
export IDEMPOTENCY_KEY="$(uuidgen)"
curl -X POST https://api.popnow.ai/api/v1/jobs/createTask \
  -H "Authorization: Bearer $POPNOW_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: $IDEMPOTENCY_KEY" \
  -d '{
  "model": "bytedance/seedance-1.5-pro/image-to-video",
  "input": {
    "prompt": "A slow aerial shot drifting over a misty pine forest at sunrise",
    "image_url": "https://media.popnow.ai/influencer/examples/marco.webp",
    "aspect_ratio": "16:9",
    "resolution": "720p",
    "duration_seconds": 5,
    "generate_audio": true
  }
}'

# 2. Copy data.taskId from the response, then poll until state is succeeded, failed, canceled or expired.
TASK_ID="TASK_ID_FROM_RESPONSE"
curl "https://api.popnow.ai/api/v1/jobs/recordInfo?taskId=$TASK_ID" \
  -H "Authorization: Bearer $POPNOW_API_KEY"

Replace the prompt and any links with your own. The API tab has the response, polling and callback reference.

Seedance 1.5 Pro API questions

All Seedance models

Seedance 2.0 runs longer, reaches 4K and adds reference scenes, but has no camera lock.

• Seedance 2.5 APIByteDance's newest: 30-second clips with native audioFrom 56 credits for a 5-second clip
• Seedance 2.0 Mini APILightweight Seedance for quick 720p drafts with soundFrom 9 credits for a 5-second clip
• Seedance 2.0 APICinematic clips up to 4K with native audioFrom 33 credits for a 5-second clip
• Seedance 2.0 Fast APIFaster Seedance 2.0 with sound at 720pFrom 17 credits for a 5-second clip
• Seedance 1.5 Pro APINative-audio clips with an optional locked cameraFrom 9 credits for a 5-second clip

Other video APIs

• MiniMax H3 APIExpressive clips with audio, up to 2KFrom 28 credits for a 5-second clip
• Kling 3.0 API4K clips, multi-shot cuts and motion controlFrom 51 credits for a 5-second clip
• Vidu Q4 Preview APIUp to 4K clips with sound and spoken dialogueFrom 34 credits for a 5-second clip
• Wan 3.0 APIUp to 30-second clips with synced audioFrom 34 credits for a 5-second clip
• Kling O3 APIKling’s unified model: create, animate, reference and edit up to 4KFrom 51 credits for a 5-second clip
• MiniMax H3 Max APIFast clips with ambience, effects and musicFrom 38 credits for a 5-second clip

More about Seedance 1.5 Pro

Try it

Seedance 1.5 Pro AI Video Generator onlineCreate videos with Seedance 1.5 Pro in PopNow

Docs

Seedance 1.5 Pro model ID and input schema in the API docsPopNow API quickstart: your first request in five minutesImage to video guide for the PopNow APIWebhooks: get Seedance 1.5 Pro results without polling