Vidu Q3 Pro API

Introduction

Vidu Q3 Pro is the Pro tier of Vidu's Q3 video line, available as a single image-to-video endpoint. You send an opening frame in image_url and a brief in prompt, both required, and get back 1 to 16 whole seconds of 540p video with audio generated in the same pass. The frame settles subject, look and the shape of the output – there is no aspect ratio field, and the image's own ratio must fall between 1:4 and 4:1 – so the prompt only has to describe what moves.

Key features

One resolution, so length is the only size decision

resolution accepts a single value, 540p, and every clip comes back at that size.

Identity comes from the still

Subject, wardrobe, framing and output shape are settled by the image, not by the prompt. Two runs from the same frame differ in movement, not in who is on screen, which is what lets a series of clips from one still cut together. It also means the video request cannot rewrite anything that was approved in the image pass.

Write the motion, then set how much

movement_amplitude sets the overall amount of motion – auto by default, or small, medium, large – while the prompt says what moves and how. When a take moves too much or too little, keep seed and the frame fixed and reword only the movement – a smaller turn, a slower walk – so the difference you see comes from that one edit rather than from a fresh draw.

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 41 credits for a 5-second clip ($0.41).

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

Use cases

Reaction sets for one character

One costume frame becomes a wink, a wave, a head tilt and a turn – four requests with the same image and four different prompts. Because identity is fixed by the frame, the set cuts together without anyone drifting between clips.

Close, rhythmic action

The forge example stays tight on a smith's chest and forearms for six seconds, lit from below by the fire, with sparks bursting on each strike of the hammer. Repeated impacts are a useful check for this endpoint: the sparks have to land on the strikes and not between them.

Vertical deliverables

Export the still at 9:16 and the clip comes back vertical.

Prompt guide & pro tips

Export the still at the shape you need

The output follows the frame: a vertical clip starts from a vertical image, a square one from a square image, and the ratio has to stay between 1:4 and 4:1. Settle wardrobe, styling and composition in the image pass as well, because the video request will not change them.

Write only what moves

Keep the prompt to the beat, the camera and the sound, and do not re-describe the picture. The published example runs 8 seconds at 540p with generate_audio on, from a drawn stage frame; its whole brief is two sentences.

She lowers the microphone, tilts her head and winks at the crowd; glowsticks sway out of focus behind her. Slow dolly-in, haze catching the backlight, crowd roar swelling.

Eight seconds from one drawn stage frame. The prompt carries the wink, the dolly-in and the crowd roar; the costume and the line work come from the image.

Write the sound into the brief

generate_audio defaults to true and the track is produced with the picture, so name the sounds you want next to the action they belong to – the stage example asks for the crowd roar to swell as the camera moves in. Set the field to false when the cut goes under a mix you already have. Background music is a separate switch, bgm, on by default; turn it off when you only want the scene’s own sound.

Compare takes with a fixed seed

Keep the frame and seed fixed while you change one phrase of the prompt, so two runs differ only by that edit. The seed makes runs comparable; it does not guarantee identical frames. If the subject needs to look different, change the still rather than the prompt – on this endpoint the image, not the text, decides who is on screen.

API quick start

Call the Vidu Q3 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 vidu/q3-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": "vidu/q3-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",
    "movement_amplitude": "auto",
    "duration_seconds": 5,
    "resolution": "540p"
  }
}'

# 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.

Vidu Q3 Pro API questions

All Vidu models

Vidu Q3 offers 720p and 1080p from the same kind of request; Q3 Pro outputs 540p only.

• Vidu Q4 Preview APIUp to 4K clips with sound and spoken dialogueFrom 34 credits for a 5-second clip
• Vidu Q3 Turbo APIFast image animation with sound, up to 16 secondsFrom 32 credits for a 5-second clip
• Vidu Q3 APIAnimate a frame for up to 16 seconds at 1080pFrom 53 credits for a 5-second clip
• Vidu Q3 Pro APIAnimate a frame with sound on by default, up to 16 secondsFrom 41 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
• Seedance 2.5 APIByteDance's newest: 30-second clips with native audioFrom 56 credits for a 5-second clip
• Kling 3.0 API4K clips, multi-shot cuts and motion controlFrom 51 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 Vidu Q3 Pro

Try it

Vidu Q3 Pro Image to Video AI onlineCreate videos with Vidu Q3 Pro in PopNow

Docs

Vidu Q3 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 Vidu Q3 Pro results without polling