Video Ad Specs

> Install the belt CLI skill: npx skills add belt-sh/cli

Video Ad Specs

Create platform-specific video ads via inference.sh CLI.

Quick Start

> Requires inference.sh CLI (belt). Install instructions

belt login

Generate a vertical video ad scene

belt app run bytedance/seedance-2-0 --input '{ prompt: vertical video, person excitedly unboxing a product, clean modern room, bright natural lighting, social media ad style, authentic feeling, ratio: 9:16, generate_audio: true }'

Platform Specifications

TikTok

Spec	Value
Aspect ratio	9:16 (vertical)
Resolution	1080 x 1920 px
Duration	5-60 seconds (15-30s recommended)
File size	Max 500 MB
Format	MP4, MOV
Sound	On by default (design with sound)
Text safe zone	150px from all edges
Hook window	1 second — first frame must grab attention

Instagram Reels

Spec	Value
Aspect ratio	9:16 (vertical)
Resolution	1080 x 1920 px
Duration	Up to 90 seconds (15-30s for ads)
Cover image	Separate upload, shows in grid
Sound	On by default
Caption area	Bottom 20% reserved for text overlay

Instagram Stories

Spec	Value
Aspect ratio	9:16
Resolution	1080 x 1920 px
Duration	Up to 15 seconds per segment
Swipe-up/Link	Available for ads
Top/bottom	14% top and 20% bottom = unsafe for key content

YouTube

Format	Aspect	Duration	Skip
Bumper	16:9	6 seconds exactly	Non-skippable
Non-skippable	16:9	15 seconds	Non-skippable
Skippable (TrueView)	16:9	Any length	Skip after 5 seconds
Shorts	9:16	Up to 60 seconds	N/A

Resolution: 1920 x 1080 (16:9) or 1080 x 1920 (Shorts)

Facebook Feed

Spec	Value
Aspect ratio	1:1 (square) or 4:5 (recommended for mobile)
Resolution	1080 x 1080 or 1080 x 1350
Duration	Up to 240 min (15-30s recommended)
Autoplay	Silent — captions are essential
Sound	85% of Facebook video is watched without sound

LinkedIn

Spec	Value
Aspect ratio	1:1 or 16:9
Resolution	1080 x 1080 or 1920 x 1080
Duration	3 seconds to 10 minutes (15-30s for ads)
Tone	Professional
Autoplay	Silent in feed

AIDA Framework for Video Ads

Phase	Time	Goal	Technique
Attention	0-3s	Stop the scroll	Pattern interrupt, bold visual, question
Interest	3-10s	Keep watching	State the problem, show relevance
Desire	10-20s	Want the solution	Show the product/outcome, social proof
Action	Final 3-5s	Click/buy/sign up	Clear CTA, urgency, offer

Hook Techniques (First 3 Seconds)

Technique	Example
Bold statement	This tool replaced my entire marketing team
Question	Why are you still doing this manually?
Surprising visual	Unexpected transformation, before/after reveal
Pattern interrupt	Start mid-action, unusual angle, bright color
Social proof	2 million people switched to this
Pain point	If you hate [common frustration], watch this

Creating Video Ads

Vertical (TikTok, Reels, Stories, Shorts)

# Hook scene (0-3s)
belt app run google/veo-3-1-fast --input '{
  "prompt": "vertical 9:16 video, close-up of hands struggling with tangled cables and messy desk, frustrated energy, shaky handheld camera, authentic social media style, bright lighting"
}'

# Solution reveal (3-15s)
belt app run bytedance/seedance-2-0 --input '{
  "prompt": "vertical video, smooth product reveal, clean wireless charging station on minimalist desk, satisfying organization transformation, bright modern room, social media ad aesthetic",
  "ratio": "9:16",
  "generate_audio": true
}'

# Add voiceover
belt app run falai/dia-tts --input '{
  "prompt": "[S1] Stop wasting time with this mess. This one product changed my entire setup. Everything charges. Everything is organized. Link in bio."
}'

# Merge video + audio
belt app run infsh/video-audio-merger --input '{
  "video": "solution-reveal.mp4",
  "audio": "voiceover.mp3"
}'

# Add captions (critical for silent autoplay)
belt app run infsh/caption-videos --input '{
  "video": "ad-with-audio.mp4",
  "caption_file": "captions.srt"
}'

### Square (Facebook, LinkedIn Feed)

belt app run google/veo-3-1-fast --input '{ prompt: square 1:1 video, professional person at desk discovering a new software tool, laptop screen showing clean dashboard, natural office lighting, corporate commercial style, satisfied expression }'

### YouTube Bumper (6 Seconds)

6-second bumper: one message, one visual, one CTA

belt app run google/veo-3-1-fast --input '{ prompt: 6 second product ad, quick montage of a sleek app being used on phone, fast cuts, modern, energetic, brand logo reveal at end, punchy and dynamic, wide 16:9 }'

Keep it tight

belt app run falai/dia-tts --input '{ prompt: [S1] Your reports. Automated. Try DataFlow free. }'

## Captions Are Mandatory

85% of Facebook and 40%+ of Instagram video is watched on mute.

### Caption Best Practices

| Rule | Reason |
|---|---|
| Always add captions | Silent viewing is the default on most platforms |
| Large, readable font | Small text is invisible on mobile |
| High contrast | White text with dark outline/background |
| Centered or bottom-third | Standard viewing position |
| Max 2 lines at a time | More text = can't be read fast enough |
| Key words in bold/color | Draws eye to important words |

Generate captions from audio

(create SRT file from your script, then burn in)

belt app run infsh/caption-videos --input '{ video: ad-video.mp4, caption_file: ad-captions.srt }'

## Ad Structure Templates

### Testimonial Ad (15-30s)

| Time | Content |
|---|---|
| 0-3s | Customer states the problem they had |
| 3-15s | How they discovered and tried the product |
| 15-25s | The specific result they achieved |
| 25-30s | Product name + CTA |

### Demo Ad (15-30s)

| Time | Content |
|---|---|
| 0-3s | The problem (text or visual) |
| 3-20s | Product demo showing the solution |
| 20-25s | Key result/benefit |
| 25-30s | CTA + offer |

### Before/After Ad (15s)

| Time | Content |
|---|---|
| 0-3s | "Before" state (messy, slow, frustrating) |
| 3-5s | Transition / product introduction |
| 5-12s | "After" state (clean, fast, satisfying) |
| 12-15s | CTA |

## Common Mistakes

| Mistake | Problem | Fix |
|---|---|---|
| No hook in first 1-3s | Viewer scrolls past | Open with pattern interrupt |
| Landscape video on TikTok/Reels | Letterboxed, looks amateur | Use 9:16 for vertical platforms |
| No captions | Most viewers watch silent | Always add captions |
| CTA too late | Viewers already left | Clear CTA within last 5 seconds |
| Too long for platform | Forced skip or dropout | Match platform duration norms |
| Same ad for all platforms | Wrong specs, wrong tone | Create platform-specific versions |
| Logo in first 3s | Feels like a commercial, gets skipped | Save branding for the end |
| Text in unsafe zones | Cut off by platform UI | Check safe zone per platform |

## Checklist

- Correct aspect ratio for target platform

- Hook in first 1-3 seconds

- Captions added (readable, high contrast)

- CTA clear and within final 5 seconds

- Duration matches platform norms

- Text outside platform unsafe zones

- Audio designed for both sound-on and sound-off

- Platform-specific version (not one-size-fits-all)

## Related Skills

npx skills add inference-sh/skills@ai-video-generation npx skills add inference-sh/skills@video-prompting-guide npx skills add inference-sh/skills@text-to-speech npx skills add inference-sh/skills@prompt-engineering

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