How to Use the Google Veo 3.1 API: image to video integration guide (2026)

Google Veo 3.1 is an image to video model by Google: Extend and continue Veo 3.1 videos with smooth motion, preserved style, and strong scene coherence. Ready-to-use REST inference API, best performance, no coldstarts, affordable pricing. On NamiFusion you can try it in the playground (exact quote shown before you submit), then call it through one unified REST API — a typical run costs about $2.80.

TL;DR

· Task type: image to video, provided by Google

· Pricing: about $2.80 per typical run ($1 = 100 credits), pay-as-you-go

· Getting started: playground (exact quote before submit) → create an API key → one POST request

· Tunable parameters: 5 (see the table below)

· No platform watermark; commercial use allowed (per the Terms of Service)

What can you build with Google Veo 3.1?

Short-form video and ad clips: go from a prompt or a single image to publishable motion content.

Product demos and concept previews: validate storyboards and visual direction cheaply before any shoot.

A social content factory: batch vertical clips and ride trending topics fast.

Remixing existing assets: image-to-video brings static work to life and extends its lifespan.

How do you call this API?

1. Sign up on NamiFusion and create a key on the API Keys page (free credits on signup).

2. Submit a task with the cURL example below, passing your key as a Bearer token.

3. Poll the task status with the returned task_uuid and read the output URLs when completed.

# 1) Submit — returns { "task_uuid": "..." }
curl -X POST "https://www.namifusion.com/api/v1/marketplace/run/google/veo3.1/video-extend" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "input": {
    "video": "https://assets-public.namifusion.com/marketplace/videos/2026-03-27/6f61861d722a.mp4",
    "prompt": "Extend the video with smooth transitions, maintaining a dreamy and cinematic style, with added vibrant colors and enhanced depth.",
    "resolution": "1080p",
    "negative_prompt": "Avoid introducing clutter, jerky movements, or overly saturated visuals."
  }
}'

# 2) Poll until status is "completed", then read the output URLs
curl "https://www.namifusion.com/api/v1/marketplace/run/tasks/TASK_UUID" \
  -H "Authorization: Bearer YOUR_API_KEY"

What parameters does it take?

video (Video): required

prompt (Prompt): optional

resolution (Resolution): optional, default "1080p"

negative_prompt (Negative Prompt): optional

seed (Seed): optional

How do you write prompts for Google Veo 3.1?

1. Subject first: lead with the actor and action, then add environment, lighting and style ("an astronaut sprinting through a neon street in the rain, cinematic, shallow depth of field").

2. Concrete nouns beat stacked adjectives: "85mm portrait lens, golden-hour backlight" works far better than "very beautiful, ultra high quality".

3. Change one variable per iteration: pin the seed to reproduce a result, tweak a single phrase at a time so you know what actually moved the output.

4. State negatives positively: instead of "no blur", ask for "sharp focus, crisp details".

How much does it cost?

Pay-per-use in credits. A typical run costs about $2.80 ($1 = 100 credits); the exact price varies with parameters like resolution or duration, and the playground shows the exact quote before you submit.