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CRT Lines Overlay: Add to Any Video Free (In Browser)

Published 2026-07-02 · 4 min read

Applying a CRT lines overlay is the fastest way to give clean digital footage the tactile texture of an old cathode-ray tube screen. Instead of downloading clunky stock video loops and tweaking blend modes, you can generate custom scanlines right over your clips in Glitchest. Here is how to build and fine-tune your overlay for free directly in your browser with zero uploads required.

Original photo before the CRT TV look glitch lookBEFORE
The CRT TV look glitch look applied in GlitchestAFTER
The CRT TV look look — before and after, straight from the editor. Base photo: cottonbro studio / Pexels.

What scanlines and phosphor glow really are

Old CRT monitors drew each frame one horizontal line at a time. Between those lit lines sat thin gaps, and your eye read the whole thing as a soft striped grid. That grid is what we call scanlines: evenly spaced dark horizontal lines laid over the image.

The second half of the effect is phosphor glow — the gentle bloom that CRT phosphors gave to bright areas. Highlights spread slightly and pick up a warm halo. On their own, scanlines can look flat and mechanical. Paired with a touch of glow, they read as genuinely nostalgic instead of like a screen filter.

When to use them

Scanlines are a tool, not a default. They shine in a few specific situations:

If your footage is already busy or high-contrast, go light. Scanlines add visual density, and too much of it buries the actual content.

How to add scanlines in Glitchest

Everything happens in your browser. There's no upload, no account.

  1. Open the editor. It loads straight into a workspace — nothing to install.
  2. Load your clip. Drop in a video or image. It stays on your device; nothing is sent to a server.
  3. Add the scanlines effect. Pick the scanline preset to lay the horizontal grid over your footage. You'll see it applied live in the preview.
  4. Layer in phosphor glow. Add a glow pass so highlights bloom the way a real tube would. This is the step that turns a flat overlay into a convincing screen.
  5. Tune the opacity and spacing. Lower the scanline opacity until the effect reads as texture, not as bars. If your tool has a line-density control, wider spacing feels vintage while tight spacing feels more like a modern panel.
  6. Export MP4. Hit export and Glitchest renders an MP4 with WebCodecs, directly in the browser. No sign-in.

Want to grab a still instead? Use Save Frame PNG to pull a single frame — handy for thumbnails or covers.

Push it further with the Time Machine dial

Once the base look is in place, the Time Machine dial lets you scrub between eras of decay, and an effect box with a fade-in and fade-out eases the effect in and out across the clip. That's useful if you want a clean opening that drifts into full CRT territory by the end.

Keep your text readable

The most common mistake is cranking scanlines so hard that titles turn to mush. A simple fix: keep the scanline opacity low anywhere text sits, and lean on glow rather than density to carry the retro feel. If a title still fights the lines, mask the effect away from that region — Glitchest supports masking so you can protect specific areas while the rest of the frame keeps its full CRT texture. Bright text on a slightly darkened band underneath almost always stays legible.

Pair it with other retro effects

Scanlines rarely travel alone. They stack naturally with a broader CRT treatment and with tape artifacts for a heavier vintage result. If you want the complete tube-TV package — barrel distortion, glow, and color bleed — start with our guide to adding a CRT effect. For a warmer, more analog tape look, combine scanlines with the steps in adding a VHS effect to video. Layering the two gives you that "recorded off the TV" quality that neither achieves on its own.

Scanlines are one of the fastest ways to shift a clip's mood, and the whole process is free and local. Load a clip, dial the intensity to taste, protect your text, and export a clean MP4 — no upload, no strings.

How to create a CRT lines overlay without downloading stock assets

Traditional video editors often rely on static PNG grids or transparent MP4 overlays to fake the look of retro displays. A procedural CRT lines overlay in Glitchest is far more flexible because you control the line thickness, gap density, and phosphor glow directly on your footage rather than fighting with blend modes.

To build your overlay, load your video or image into the editor and choose a scanline or CRT preset chip. A colored effect block appears on your timeline. You can drag the ends to control when the lines appear, adjust the fade handles for smooth transitions, and tweak the 0-100 parameter knobs in the inspector to set the line sharpness and opacity.

Because everything runs in-browser, you can preview the overlay live without rendering pauses. When you are satisfied with the look, click Export (MP4) to render your video or Save Frame (PNG) to grab a still image.

The exact settings

RECIPECRT TV look

Start from the CRT TV preset, then set:

RGB Split18
Brightness53
Contrast58
Scanlines40
Flicker10
CRT Curve + Glow74
Vertical Roll (TV)6
Open this look in the editor →

Everything else stays at its default — tweak it, then copy your own look as JSON or a link from inside the editor to share it.

Try it now — add this look to your own clip, free and in your browser.

Open the editor →

FAQ

What are scanlines?

Thin dark horizontal lines that mimic an old CRT monitor's raster, giving footage a retro on-screen feel.

Do scanlines cost anything to add?

No — adding scanlines and exporting the result is free, with no account and no paywall on the render.

Do scanlines hurt readability?

Keep them subtle under text; Glitchest lets you tune the opacity so titles stay legible.

How can I add a CRT scanline overlay to my video?

You can apply a customizable CRT scanline overlay to your video or image for free using Glitchest at /app/. The editor runs entirely in your browser with no account or file upload required.