genai-video

name	genai-video
description	Generate videos using Google GenAI Veo 3.1 model via CLI. Use when the user asks to create videos, generate animations, make AI video content, do image-to-video transformations, interpolate between frames, or create cinematic shots with camera movement.

GenAI Video Generation Skill

Generate videos using the genai-cli video command with Veo 3.1.

Uses fast mode by default ($0.15/sec) for quick generation. Use --quality-mode for higher quality output ($0.40/sec).

Quick Start

# Basic video generation (async - returns job ID)
uv run genai-cli video "sunset over ocean, gentle waves"

# Wait for completion (blocking)
uv run genai-cli video "sunset over ocean" --wait

# Image-to-video (use existing image as starting frame)
uv run genai-cli video "camera pullback revealing the scene" --input ./image.png --wait

# First/last frame interpolation
uv run genai-cli video "smooth morph transition" --input ./start.png --last-frame ./end.png --wait

CLI Reference

uv run genai-cli video [OPTIONS] PROMPT

Options:
  --aspect, -a      Aspect ratio: 16:9 or 9:16 (default: 16:9)
  --duration, -d    Duration in seconds: 4, 6, or 8 (default: 8)
  --resolution, -r  Resolution: 720p, 1080p, or 4k (default: 720p)
  --seed, -s        Random seed for reproducibility
  --audio           Generate video with audio
  --wait, -w        Wait for completion (blocking mode)
  --input, -i       First frame image for image-to-video
  --last-frame, -l  Last frame image (requires --input)
  --negative, -n    What NOT to include in video
  --ref             Reference images for style (up to 3, 16:9 only)
  --ref-type        Reference image type: style (aesthetic) or asset (character/object)
  --extend, -e      Video file URI to extend
  --person-gen      Person generation: allow_all or allow_adult
  --quality-mode    Use quality model (slower, higher quality, $0.40/sec)
  --enhance         Auto-improve prompt for better video quality
  --fps             Frames per second (e.g., 24 for cinematic, 60 for smooth)
  --compression     Compression quality: optimized (smaller) or lossless (larger)
  --variations, -v  Number of video variations to generate (1-4)
  --mask, -m        Mask image for targeted editing (requires --input)
  --mask-mode       Mask mode: insert, remove, remove-static, outpaint
  --output, -o      Output directory (default: ./genai_outputs/)
  --json            Output as JSON

Model Modes

Fast Mode (Default)

Uses veo-3.1-fast-generate-preview model at $0.15/second. Optimized for speed and business use cases.

uv run genai-cli video "sunset over ocean" --wait

Quality Mode

Uses veo-3.1-generate-preview model at $0.40/second. Higher quality output for premium content.

uv run genai-cli video "cinematic sunset scene" --quality-mode --wait

Prompt Enhancement

Auto-improve your prompts for better video quality:

# Let the model enhance your simple prompt
uv run genai-cli video "sunset" --enhance --wait

Frame Rate Control (FPS)

Control frames per second for different effects:

# Cinematic 24fps (film-like)
uv run genai-cli video "dramatic scene" --fps 24 --wait

# Standard 30fps
uv run genai-cli video "product demo" --fps 30 --wait

# Smooth 60fps (action/sports)
uv run genai-cli video "slow motion water" --fps 60 --wait

Compression Quality

Control file size vs quality tradeoff:

# Optimized - smaller file size (default behavior)
uv run genai-cli video "social media clip" --compression optimized --wait

# Lossless - larger file, no quality loss (for archival/editing)
uv run genai-cli video "product demo" --compression lossless --wait

Multiple Variations

Generate multiple video variations from the same prompt:

# Generate 3 different versions
uv run genai-cli video "abstract animation" --variations 3 --wait

# Generate 4 variations for A/B testing
uv run genai-cli video "hero scene" --variations 4 --wait

Modes

Async Mode (Default)

Returns immediately with a job ID:

uv run genai-cli video "flying through clouds"
# Output: Job ID: models/veo-3.1.../operations/abc123

Blocking Mode (--wait)

Waits for video to complete and downloads it:

uv run genai-cli video "flying through clouds" --wait
# Output: ✓ Saved: genai_outputs/video_20260114_123456_1.mp4 (2.1 MB)

Image-to-Video

Use an existing image as the starting frame for your video:

# Camera pullback from an image
uv run genai-cli video "Dramatic camera pullback revealing the full scene" \
  --input ./my_image.png \
  --aspect 9:16 \
  --wait

# Animate a still image
uv run genai-cli video "Gentle movement, hair blowing in wind" \
  --input ./portrait.png \
  --wait

First & Last Frame Interpolation

Generate videos by specifying both the starting and ending frames. The model interpolates smooth motion between them:

# Morph between two images
uv run genai-cli video "Smooth transition with dramatic lighting" \
  --input ./start_frame.png \
  --last-frame ./end_frame.png \
  --wait

# Scene transformation
uv run genai-cli video "Day transforms to night, cinematic transition" \
  --input ./day_scene.png \
  --last-frame ./night_scene.png \
  --aspect 16:9 \
  --wait

Requirements:

• Both images must match the video's aspect ratio
• --last-frame requires --input (first frame) to be set
• Duration defaults to 8 seconds for interpolation

Reference Images for Style/Assets

Use up to 3 reference images to guide the video. Two reference types are available:

Style References (Default)

Transfer aesthetic elements like colors, lighting, and visual style:

# Style-guided generation (default)
uv run genai-cli video "A person walking through a forest" \
  --ref ./style1.png --ref ./style2.png \
  --ref-type style \
  --aspect 16:9 \
  --wait

Asset References

Maintain character or object consistency across scenes:

# Character consistency
uv run genai-cli video "The character walks through a city" \
  --ref ./character_front.png --ref ./character_side.png \
  --ref-type asset \
  --aspect 16:9 \
  --wait

# Object consistency
uv run genai-cli video "The product rotates on display" \
  --ref ./product_view1.png --ref ./product_view2.png \
  --ref-type asset \
  --aspect 16:9 \
  --wait

Note: Reference images only work with 16:9 aspect ratio and require duration of 8 seconds.

Video Extension

Extend a previously generated Veo video:

# Extend an existing video
uv run genai-cli video "Continue the scene with more action" \
  --extend "files/video-file-id" \
  --wait

Note: Extension requires duration of 8 seconds.

Negative Prompts

Specify what NOT to include in your video:

uv run genai-cli video "A serene beach scene" \
  --negative "people, crowds, text, watermarks" \
  --wait

Person Generation Control

Control how people are generated in videos:

# Allow all person generation (text/extension mode)
uv run genai-cli video "People walking in park" \
  --person-gen allow_all \
  --wait

# Allow adult-only generation (image/interpolation/references)
uv run genai-cli video "Professional meeting" \
  --input ./office.png \
  --person-gen allow_adult \
  --wait

Audio Generation

Generate videos with synchronized audio:

uv run genai-cli video "Ocean waves crashing on beach with seagulls" \
  --audio \
  --wait

Resolution & Duration

High Resolution (1080p/4K)

# 1080p requires 8s duration
uv run genai-cli video "Cinematic landscape" \
  --resolution 1080p \
  --duration 8 \
  --wait

# 4K also requires 8s duration
uv run genai-cli video "Ultra HD nature scene" \
  --resolution 4k \
  --duration 8 \
  --wait

Duration Options

# 4 seconds
uv run genai-cli video "Quick action shot" --duration 4 --wait

# 6 seconds
uv run genai-cli video "Medium scene" --duration 6 --wait

# 8 seconds (default, required for 1080p/4K/extension/references)
uv run genai-cli video "Full scene" --duration 8 --wait

Camera Movement Prompts

For image-to-video, describe the camera movement:

Movement	Prompt Example
Pullback	"Camera slowly pulls back to reveal the scene"
Push in	"Camera pushes in toward the subject"
Pan	"Camera pans left across the scene"
Tilt	"Camera tilts up to show the sky"
Dolly	"Smooth dolly shot moving parallel to subject"
Crane	"Crane shot rising above the scene"
Static	"Subtle movement, subject remains still"

Video Masking (Targeted Editing)

Use masks to edit specific regions of videos:

Insert Mode

Add new objects into a masked region:

uv run genai-cli video "add a butterfly flying" \
  --input ./scene.png \
  --mask ./butterfly_area_mask.png \
  --mask-mode insert \
  --wait

Remove Mode

Remove tracked objects from video (tracks object through frames):

uv run genai-cli video "remove the car smoothly" \
  --input ./street_scene.png \
  --mask ./car_mask.png \
  --mask-mode remove \
  --wait

Remove-Static Mode

Remove static objects (watermarks, logos, fixed elements):

uv run genai-cli video "clean background" \
  --input ./video_frame.png \
  --mask ./watermark_mask.png \
  --mask-mode remove-static \
  --wait

Outpaint Mode

Expand the video beyond its original frame:

uv run genai-cli video "expand the landscape view" \
  --input ./cropped_scene.png \
  --mask ./outpaint_mask.png \
  --mask-mode outpaint \
  --wait

Mask Requirements:

• Mask must be same dimensions as input image
• White areas (255) = region to modify
• Black areas (0) = region to preserve
• --mask requires --input (first frame image)

Output

Videos are saved to ./genai_outputs/ by default:

• video_YYYYMMDD_HHMMSS_1.mp4

Prompt Tips

1. Describe movement: "Camera slowly pulls back", "Gentle zoom in"
2. Include atmosphere: "Moody lighting", "Dust particles in air"
3. Use audio cues: With --audio, describe sounds in prompt
4. Be cinematic: "Dramatic", "Cinematic", "Film-like"
5. Use negative prompts: Exclude unwanted elements with --negative

API Constraints

Feature	Constraint
1080p/4K resolution	Requires duration = 8
Reference images	Requires 16:9 aspect, duration = 8
Video extension	Requires duration = 8
Reference images	Max 3 images

Prerequisites

API key must be configured:

uv run genai-cli auth set-key