Real-time waveform, vectorscope, RGB parade, and frame-diff analysis for any video on any webpage — no capture card, no software, no subscription.
Works on YouTube · Vimeo · Twitch · Frame.io · Any streaming platform
Each scope is rendered in a dedicated panel on a separate window — overlay-free, always visible while your video plays.
The waveform plots luminance values (0–100 IRE) mapped horizontally across the frame width. Crush blacks, blown highlights, and uneven exposures are immediately visible as the plot hits the floor or ceiling. ScopeLab renders luma and optionally RGB channels so you can evaluate both overall exposure and individual colour balance simultaneously.
The vectorscope plots hue and saturation on a polar diagram. Broadcast-safe targets for Red, Green, Blue, Cyan, Magenta, and Yellow are marked so you can check if your colours hit specification. When comparing two feeds, neutral content should cluster at the centre — any deviation tells you exactly which hue is drifting and by how much.
RGB Parade splits the waveform into three separate columns — Red, Green, and Blue — each showing that channel's luminance distribution across the frame width. If a clip is balanced, all three channels should track similarly. A tint shows up as one channel riding higher than the others, making it easy to diagnose and correct colour casts even before applying a LUT.
Frame Diff plots the pixel-level difference between Source A and Source B over time. When comparing an original and a compressed version of the same content, spikes reveal where the encoder introduced artifacts. When monitoring a live feed against a reference, sustained differences indicate a colour grade mismatch or a signal path problem — even before your eye catches it.
ScopeLab is designed for speed — from extension click to live scopes in under 10 seconds.
Navigate to YouTube, Vimeo, Frame.io, a live stream, or any page containing HTML5 video elements — even inside iframes.
The popup opens and automatically detects all video elements on the page, showing you how many it found.
Auto Detect picks the two largest videos automatically. Scan & Select lets you click overlays to assign Source A and Source B manually. Crop Region lets you draw a box over any part of any video.
A dedicated scope window opens on your second monitor (if available). All four scopes update in real time as your video plays. SMPTE timecode and audio level meters run live alongside the scopes. Move it anywhere, resize it, leave it running.
One click. ScopeLab ranks all videos by rendered size and assigns the two largest as A (left) and B (right). Perfect when you have a side-by-side comparison player or two streams open.
Coloured overlays appear on every video element. Click one to set it as Source A, then click another for Source B. Shows resolution and lets you pick exactly which element to monitor.
Drag a resizable box over any region of the page — including inside a letterboxed or pillarboxed player. ScopeLab analyses only the pixels inside your box, ignoring surrounding UI chrome.
Right-click any video element directly and choose Set as Source A or Set as Source B from the context menu — no popup needed.
If you're evaluating, grading, encoding, or comparing video in a browser, ScopeLab gives you the data your eyes can't.
Review client-deliverable content streamed from Frame.io or Vimeo without needing a hardware scope. Compare a LUT-on vs LUT-off version side by side on the vectorscope and confirm your grade hits broadcast spec before sending approval links.
Point ScopeLab at a streaming preview URL and watch the waveform for level drops or the vectorscope for colour shifts in real time — no hardware outboard required. Catch encoder problems the moment they happen.
Play two versions of the same timeline back in the browser — original and export, or two camera angles — and use Frame Diff to confirm they're identical or RGB Parade to spot any encode-induced colour shift.
Review inbound footage against your brand's colour specification or a reference clip. Flag clips that deviate from spec before they go to editorial, without shipping hardware scopes to every reviewer.
When generating shots across different AI platforms, use the vectorscope and waveform to ensure colour temperature and exposure match between clips — catching inconsistencies before the assembly edit.
Load any YouTube video and open ScopeLab to understand how scopes respond to different lighting situations, colour grades, and camera exposures — a free and practical way to build scope fluency.
ScopeLab runs entirely in Chrome — no accounts, no cloud, no data sent anywhere. All analysis happens locally in your browser.
Download the ZIP from GitHub releases or the Chrome Web Store (when listed). Unzip to a folder you'll keep — Chrome loads it directly from that location.
In Chrome, navigate to chrome://extensions or click the puzzle-piece icon → Manage Extensions.
Toggle Developer mode in the top-right corner of the Extensions page. This is required for side-loaded extensions.
Click Load unpacked and navigate to the scopelab-extension folder. Chrome loads it immediately — no restart needed.
Click the puzzle icon in Chrome's toolbar and pin ScopeLab so the icon is always visible. Navigate to any video page, click the icon, and start scoping.
v1.0 · Chrome · Free
DRM-protected streams (Netflix, Disney+) cannot be captured due to browser security restrictions — this is a browser limitation, not a ScopeLab limitation.
No. DRM-protected streams use Encrypted Media Extensions (EME), which prevent the browser from reading pixel data from the video frame. This is a security boundary enforced by Chrome — ScopeLab cannot access encrypted video content. It works on any non-DRM video, including YouTube, Vimeo, Frame.io, streaming preview URLs, and self-hosted players.
ScopeLab throttles frame capture to 10fps and downscales frames to a maximum analysis width of 640px before processing. On a modern machine the CPU overhead is minimal — comparable to having a lightweight tab open. The scope window only draws when new frame data arrives, so it's idle when video is paused.
No. All frame capture and analysis happens entirely within your browser. Pixel data is processed locally using the Canvas API and is never transmitted to any server. ScopeLab has no backend — it's purely a local Chrome extension.
Yes. When only one video is available, ScopeLab assigns it as both Source A and Source B. The waveform and vectorscope still run, though Frame Diff will show zero difference. Crop Region mode also lets you compare two different regions of the same video side by side.
Some players embed video inside shadow DOM elements or cross-origin iframes. ScopeLab searches shadow roots at any depth and same-origin iframes automatically. If the player uses cross-origin iframes (e.g., an embedded YouTube player on a third-party site), the video may not be accessible — navigate directly to the platform instead.
ScopeLab is a Chrome extension, so it works on any OS that runs Chrome: Windows, macOS, and Linux. The scope window positions itself on a second monitor automatically if one is detected.
ScopeLab is free to use today. A Pro tier with advanced features is planned for the future.
Everything you need to scope browser video professionally — no card, no account, no limit.
Advanced tools for professional colourists, video engineers, and QC teams.