LuttieHow to Color Grade a Video Frame in Your Browser
You don't need Premiere or Resolve to color grade video footage. How to extract a frame, grade it, and export the look as a LUT — all in the browser.
Building a color grade from a still image is faster than grading in a timeline — you're not waiting for render previews, you're not navigating track layers, and you can see your full grade in real time. The workflow is: extract the right frame, grade it, export the LUT, apply it in your NLE.
This is how most professional colorists approach a new project. Lock a reference frame, build the grade on that frame, apply it to the cut. Luttie lets you do this entirely in the browser.
The workflow
1. Open the editor and drop your video
Go to luttie.app/editor. Drop your MP4, MOV, or WebM file directly onto the canvas area.
A modal appears with a video player and a scrubber.
2. Scrub to the right frame
The frame you pick matters. Choose a frame that's representative of your footage — a shot with a mid-toned subject in the main lighting condition you're grading for. Avoid:
- Extreme highlights or shadows that aren't typical
- Transitional frames (cuts, fades)
- Frames that are uniquely lit compared to the rest of the clip
The goal is a frame that, when you grade it to look right, will also make the rest of your footage look right.
3. Extract and grade
Click Extract frame. The frame loads into the Luttie grading canvas exactly like a still image.
From here, use any of the grading tools:
- Basic correction — exposure, contrast, whites, blacks, saturation
- Curves — per-channel RGB control for precise tonal shaping
- Color wheels — shadows, midtones, highlights color push
- HSL secondary — isolate and correct specific color ranges
- Color match — drop a reference image to match its palette automatically
4. Export the LUT
Once the grade looks right, click Export LUT (.cube) or Export LUT Pack (.zip) for 50/75/100% versions.
Your grade is now a .cube file — apply it to the full video in your NLE.
Which frame to pick
For narrative / scripted content: pick a close-up of your lead actor in the key lighting setup for the scene. Skin tone response is the hardest thing to get right — if it looks good on skin, the rest will follow.
For drone / landscape footage: pick a wide shot with a full tonal range — sky, shadows, and mid-tones all visible. DJI D-Log M and Sony S-Log3 tend to look green-cast before grading; pick a frame that makes that obvious so your grade fully corrects it.
For event / documentary: pick a representative wide shot from the main location. Grading for the room is more important than grading for a single face.
Supported formats
| Format | Works? | Notes |
|---|---|---|
| MP4 (H.264) | ✅ | Universal — works in all browsers |
| MP4 (H.265/HEVC) | ✅ | Works in Chrome, Safari; limited Firefox |
| MOV (H.264) | ✅ | Works in all browsers |
| WebM | ✅ | Works in all browsers |
| MKV | ✅ | Works in most modern browsers |
| MOV (ProRes) | ❌ | Browser can't decode ProRes — export an H.264 proxy |
If you're shooting ProRes, export a low-res H.264 proxy from your camera app or Finder (Quick Look → Share) before dropping it into Luttie.
Applying the LUT in your NLE
DaVinci Resolve: Add a LUT node on the color page → right-click → Apply LUT → navigate to your .cube file.
Premiere Pro: Lumetri Color panel → Creative → Look → browse to your file. Use the Intensity slider to blend.
Final Cut Pro: Effects → Color → Custom LUT → assign your file.
CapCut: Effects tab → Filter → Import.