Why Does HUD and Line-Art Wallpaper Belong in a Lossless PNG?

Keep HUD and line-art wallpapers as PNG because JPEG is built to hide errors in photographs, not in one-pixel strokes. A thin cyan tick on black is the worst case for 8x8 blocks and 4:2:0 chroma. You get ringing, colored fringes, and broken corners. PNG stores the pixels. The ticks stay ticks.

This is the close-up of the PNG versus JPEG choice. It is only about edges. How you may use the file is on the license page.

What JPEG does to one-pixel lines

JPEG divides the picture into 8x8 blocks and throws away high frequencies. A one-pixel line is a high frequency. The encoder cannot keep it and hit a small file size, so it approximates. The approximation is a ripple on both sides of the line. On black, that ripple is visible as a ghost stroke.

Chroma subsampling makes it worse. Common JPEG is 4:2:0. Color is stored at half width and half height. A pure cyan line on black has a color change that the chroma grid cannot place. The decoder spreads the cyan into neighboring pixels as pink and green mush. The line looks dirty even if the luma is not bad.

Type in a HUD still is a stack of those lines. Small readout letters become blotches. Corner brackets lose the mitre. A circle of hash marks becomes a serrated ring with a halo.

Quality 90 does not save you if 4:2:0 is on. Quality 100 with 4:4:4 is closer, and then the JPEG is often larger than the PNG and still not lossless. There is no prize for that file.

A second save is the usual disaster. You download a PNG, send it through a chat app, the app uploads a JPEG, you save that back, and you set the desktop to the copy. Each pass adds another ripple. The original on this site never had the ripple. The copy does.

Why PNG keeps HUD edges

PNG-24 (or PNG-32 with unused alpha) stores each 8-bit channel. A pixel that is 0, 255, 255 stays 0, 255, 255. There is no block grid and no chroma siting. You can open and save the file all day. The ticks do not drift.

PNG compression looks for repeated bytes, not for frequencies it can drop. A HUD on a real black field compresses well because black runs are long. A noisy HUD with a dithered glow compresses less well and still stays exact. Size is the only cost. On a 4K still that size is megabytes, not hundreds of megabytes.

Indexed PNG-8 is not a free upgrade. It can posterize a glow and still keep the ticks if you are lucky with the palette. Do not convert a 4K HUD to 256 colors unless you have inspected the blooms at 100%. The archive originals are not PNG-8.

Windows, macOS, GNOME, Plasma, and feh all set PNG wallpapers. There is no compatibility reason to flatten a HUD to JPEG "so Windows can read it." Windows reads PNG. The Windows Picture path accepts it.

How to avoid a second lossy save

Download the PNG from the archive with the site's download control, not with a long-press on the preview. The preview is a 1920-pixel WebP. WebP is another lossy or at least another generation.

Keep the original in the local folder. Set wallpaper from that path. Do not drop the file into WhatsApp, Discord, or Instagram and save the result.

If you crop for ultrawide or phone, export PNG. Editors default to JPEG in some export dialogs. Change the dropdown.

If you already have a dirty copy, do not run a "sharpen HUD" filter. Sharpening a ripple makes two ripples. Go back to the original PNG. If you cannot, pick another still. You cannot reconstruct a one-pixel line from a 4:2:0 JPEG.

Zoom to 100% on a tick before you call the file good. At fit-to-window, JPEG mush hides. On a 4K panel the mush is the desktop.

Gradient stills are more forgiving. If your desk is a gradient and not a HUD, JPEG is a size choice, not a look failure. Line art does not get that choice.

For what a HUD still is doing on a desk at all, including the overlay confusion, use what is a HUD wallpaper.