Video Generation

Generate videos from text descriptions or animate images using Google Veo 3.1 Fast via the Rebyte data proxy.

Authentication

IMPORTANT: All API requests require authentication. Get your auth token and API URL by running:

AUTH_TOKEN=$(/home/user/.local/bin/rebyte-auth)
API_URL=$(python3 -c "import json; print(json.load(open('/home/user/.rebyte.ai/auth.json'))['sandbox']['relay_url'])")

Include the token in all API requests as a Bearer token, and use $API_URL as the base for all API endpoints.

Model

Model	ID	Audio	Notes
Veo 3.1 Fast	veo-3.1-fast	Yes (native)	Default. Cost-efficient, up to 1080p.

Note: Video generation is a long-running operation. It typically takes 30–120 seconds to complete. Do not set short timeouts.

---

Text-to-Video

curl -X POST "$API_URL/api/data/video/generate" \
  -H "Authorization: Bearer $AUTH_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "prompt": "A slow-motion close-up of espresso being poured into a cup, steam rising, warm golden window light, shallow depth of field, cinematic",
    "aspectRatio": "16:9",
    "duration": 8
  }'

Image-to-Video

Animate a still image by providing it as base64.

curl -X POST "$API_URL/api/data/video/generate" \
  -H "Authorization: Bearer $AUTH_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "prompt": "The flower slowly blooms in timelapse, petals unfolding",
    "image": "<base64-encoded-image>",
    "imageMimeType": "image/png",
    "duration": 8
  }'

---

Parameters

Name	Type	Required	Default	Values	Description
prompt	string	Yes	—	—	Text description of the video
image	string	No	—	—	Base64-encoded source image (for image-to-video)
imageMimeType	string	No	image/png	image/png, image/jpeg, image/webp	MIME type of source image
resolution	string	No	720p	720p, 1080p	Video resolution. 1080p requires duration: 8
aspectRatio	string	No	16:9	16:9, 9:16	Landscape or portrait
duration	number	No	8	4, 6, 8	Seconds. Only 4, 6, or 8. 1080p requires 8

---

Response

{
  "video": {
    "url": "https://api.rebyte.ai/api/public/artifacts/<workspaceId>/veo-1712345678-a1b2c3d4.mp4",
    "mimeType": "video/mp4",
    "model": "veo-3.1-fast-generate-preview",
    "resolution": "720p",
    "aspectRatio": "16:9",
    "duration": 8
  }
}

The video URL is already publicly downloadable — the relay has stored the video in the workspace's artifact store on your behalf. You can:

• Share directly: embed video.url in HTML, markdown, or chat. No auth required.

• Download locally if you need the bytes (e.g. to pass to ffmpeg or re-upload elsewhere):

  curl -L -o output.mp4 "<video-url>"
  

You do not need to re-upload the video to the Artifact Store — it's already there.

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Writing Effective Video Prompts

Good video prompts describe motion and time, not just a static scene. Include:

• Subject and action: What is happening, who/what is moving
• Camera work: Pan, tilt, zoom, tracking shot, drone shot, static, handheld
• Scene setting: Location, time of day, weather, environment
• Style: Cinematic, documentary, slow motion, timelapse, animation
• Mood and atmosphere: Lighting, color grading, emotional tone
• Temporal flow: What happens first, then next

Prompt Examples

Simple:

A drone shot slowly flying over a misty mountain range at sunrise

Cinematic:

A slow-motion close-up of a coffee cup being filled with espresso, steam rising, warm golden light from a nearby window, shallow depth of field, cinematic color grading

Action:

A tracking shot following a cyclist riding through autumn leaves on a tree-lined path, golden hour lighting, leaves swirling in their wake

Abstract:

Flowing liquid mercury forming geometric shapes in zero gravity, reflecting prismatic light, smooth transitions between forms, dark background, studio lighting

Narrative:

A time-lapse of a flower blooming in a garden, starting from a tight bud to full bloom, morning dew evaporating, soft natural lighting, macro lens perspective

Camera Movement Keywords

Keyword	Effect
Static	Fixed camera, no movement
Pan	Horizontal rotation (left/right)
Tilt	Vertical rotation (up/down)
Zoom in/out	Moving closer or further
Tracking/dolly	Camera moves alongside subject
Drone/aerial	Overhead or elevated perspective
Handheld	Slight natural camera shake
Orbit	Camera circles around subject
Crane	Vertical camera movement (rising/lowering)

Style Keywords

Keyword	Effect
Cinematic	Film-quality, 24fps feel, color graded
Documentary	Natural, observational
Slow motion	Time-stretched action
Timelapse	Compressed time
Hyperlapse	Moving timelapse
Animation	Animated/cartoon style
Vintage/retro	Film grain, muted colors
Noir	High contrast, dramatic shadows

---

Using with Python

import subprocess
import requests
import base64
import json
from pathlib import Path

AUTH_TOKEN = subprocess.check_output(["/home/user/.local/bin/rebyte-auth"]).decode().strip()
with open('/home/user/.rebyte.ai/auth.json') as f:
    API_URL = json.load(f)['sandbox']['relay_url']

HEADERS = {"Authorization": f"Bearer {AUTH_TOKEN}"}

def generate_video(prompt, image_path=None, aspect_ratio="16:9", resolution="720p", duration=8):
    payload = {"prompt": prompt, "aspectRatio": aspect_ratio, "resolution": resolution, "duration": duration}
    if image_path:
        payload["image"] = base64.b64encode(Path(image_path).read_bytes()).decode()
        ext = Path(image_path).suffix.lower()
        payload["imageMimeType"] = {'.png': 'image/png', '.jpg': 'image/jpeg', '.jpeg': 'image/jpeg', '.webp': 'image/webp'}.get(ext, 'image/png')
    return requests.post(f"{API_URL}/api/data/video/generate", headers=HEADERS, json=payload, timeout=300).json()

def save_video(result, filepath):
    if "video" not in result:
        print(f"Error: {result.get('error', 'Unknown error')}"); return
    # video.url is a public relay URL — no auth header needed.
    resp = requests.get(result["video"]["url"])
    resp.raise_for_status()
    Path(filepath).write_bytes(resp.content)
    print(f"Saved to {filepath}")

result = generate_video("A drone shot over a misty mountain range at sunrise, cinematic")
save_video(result, "mountains.mp4")

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Error Handling

Error	Cause	Fix
durationSeconds is out of bound	Invalid duration value	Use exactly 4, 6, or 8
Veo generation failed	Content safety filter	Rephrase the prompt
Veo operation timed out	Generation took >6 min	Simpler prompt or shorter duration

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Important Notes

• Generation time: 30–120 seconds. The API call blocks until ready.
• Audio: Veo 3.1 generates native audio matching the scene.
• Video URL: Public relay URL — share directly, no auth needed. Already stored in the workspace artifact store.
• SynthID: All generated videos include invisible watermarking.
• Duration: Only 4, 6, or 8 seconds. No arbitrary values.
• Aspect ratio: Only 16:9 (landscape) or 9:16 (portrait).
• Shorter durations tend to produce higher quality results.
• Be specific about camera movement — it dramatically changes the result.