AI-powered frame scoring

AI Social Media Frame Picker

Stop scrubbing the timeline looking for a usable thumbnail. Upload a video and the AI scores every keyframe on sharpness, lighting, composition and faces, then hands you the best image for each platform — free, private, and entirely in your browser.

Computer Vision & AI Mechanics

An AI Thumbnail Generator That Actually Looks at Your Footage

Most tools that promise to extract the best image from a video do something much simpler than they imply: they grab a frame at 10%, 50% and 90% of the duration and let you choose. If your subject blinked at the halfway mark, that is what you get.

How True In-Browser AI Frame Selection Works:The video is decoded locally in your browser. Scene changes are detected by comparing colour histograms between samples, and keyframes are extracted around those boundaries. Every candidate then goes through a computer-vision scoring pass that measures sharpness with a Laplacian variance kernel, estimates motion blur from directional gradients, checks exposure clipping, measures contrast and colour vibrancy, and evaluates composition against a rule-of-thirds grid.

The output is a single quality score from 0 to 100, plus the specific reasons behind it. A frame scoring 96 will tell you why: excellent sharpness, good lighting, centred subject, no motion blur, human face detected. When a frame scores badly, you also see why — making thumbnail selection fast and effortless.

One Video, a Best Frame for Every Platform

Different social platforms demand different aspect ratios and visual priorities. Our AI re-weights scoring metrics for each destination:

🏆16:9

Best Overall

Recommended: 1920×1080px

The single strongest frame in the video on pure technical quality.

16:9

Best YouTube Thumbnail

Recommended: 1280×720px

High-contrast, sharp and readable when shrunk to a sidebar tile.

📷1:1

Best Instagram Post

Recommended: 1080×1080px

Square-safe framing with vivid colour and a centred subject.

📖9:16

Best Instagram Story

Recommended: 1080×1920px

Vertical-friendly frame with the subject clear of UI overlays.

💼1.91:1

Best LinkedIn Post

Recommended: 1200×628px

Clean, well-exposed and professional — no motion artefacts.

📌2:3

Best Pinterest Pin

Recommended: 1000×1500px

Tall, colour-rich and detailed — built for a scrolling grid.

🐦16:9

Best X Post

Recommended: 1600×900px

Reads instantly at small size in a fast-moving timeline.

🎵9:16

Best TikTok Cover

Recommended: 1080×1920px

Bright, punchy vertical frame with a strong central subject.

🟢9:16

Best WhatsApp Status

Recommended: 1080×1920px

Vertical, well-lit and clear even after aggressive recompression.

🖥16:9

Wallpaper

Recommended: 2560×1440px

Maximum resolution and detail, subject placed off-centre.

Why Creators Need a Better Way to Choose a Thumbnail

01. Eliminate Scrubber Bias

Timeline scrubbers are too small (120px) to spot motion blur or soft focus that destroys full-size 1080p thumbnails.

02. Exposure Guard

Highlight clipping destroys pixel data permanently. The AI penalises blown-out frames so you never publish ruined highlights.

03. Eye & Face Lock

Open eyes and centered expressions measurably boost click-through rates. The scoring engine automatically prioritises non-blinking faces.

How the Scoring Engine Works

Scoring runs in a background Web Worker off the main thread. Here are the 8 key factors evaluated per candidate frame:

🔍

Sharpness & Clarity

Laplacian Variance

Measures edge density across the luminance channel. Disqualifies soft or out-of-focus frames.

Motion Blur Filter

Directional Gradients

Separates intentional cinematic depth-of-field from smeared subject movement.

☀️

Exposure & Contrast

Histogram Spread

Evaluates dynamic range while imposing strict penalties on crushed shadows and clipped highlights.

🎨

Color Vibrancy

Mean Saturation

Rewards balanced, rich saturation while avoiding flat desaturated or garish oversaturated frames.

📐

Composition Grid

Rule-of-Thirds

Scores visual weight and subject alignment against classic 3x3 grid intersections.

👁️

Faces & Open Eyes

Computer Vision

Detects face position, size, and eye visibility to maximize viewer engagement.

🚫

Black Frame Disqualification

Luminance Threshold

Excludes zero-value black frames from fade-ins and fade-outs outright.

👯

Duplicate Filtering

Perceptual Hashing

Groups visually identical frames and keeps only the highest-scoring candidate.

Frequently Asked Questions

Q. How does the AI choose the best frame from my video?

Every candidate frame is measured on sharpness, motion blur, brightness, contrast, exposure clipping, colour vibrancy, composition against a rule-of-thirds grid, and whether a face is present and well positioned. Those measurements are combined into a single 0-100 score, then weighted again for each platform, so a YouTube thumbnail and an Instagram story can win on different criteria. Nothing is chosen at random.

Q. Is my video uploaded to a server?

No. Decoding, analysis and export all run inside your browser using the standard video and canvas APIs. Your file never leaves your device, which is why the tool works on unlisted footage and client work without a confidentiality problem.

Q. What video formats and sizes are supported?

Any format your browser can play, which in practice covers MP4 (H.264), MOV and WEBM, up to 500MB. Very long videos are sampled more sparsely rather than rejected, so a feature-length file still returns results in reasonable time.

Q. Why does it extract 80-150 frames instead of every frame?

A 30-second clip at 30fps contains 900 frames, and the overwhelming majority are near-identical to their neighbours. The tool detects scene changes and samples adaptively around them, then removes near-duplicates with a perceptual hash. You get the same best frame in a fraction of the time and memory.

Q. What resolution are the downloaded images?

Downloads are re-decoded from the original video at full resolution, not taken from the preview thumbnails. You can export at the source resolution, at 1080p or 720p, or at each platform’s recommended dimensions, in PNG, JPEG or WEBP.

Q. Does it work without face detection?

Yes. Face detection uses the browser’s native FaceDetector API where available. Where it is not, the tool falls back to skin-tone and region-of-interest heuristics and continues scoring on every other factor. The results panel tells you which mode was used.

Q. Is the AI Social Media Frame Picker free?

Yes, it is free and needs no account. All processing happens locally, so there are no per-video costs to pass on.

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