* Decode webp in the shell
The background and the lock screen are drawn by Quickshell, so they
decode through Qt, which ships handlers for png, jpeg and gif but not
webp. QImageReader answers "Unsupported image format" and the layer
comes up blank. Any third-party theme shipping a .webp background hits
this today, even though every path that goes looking for a background
already globs the extension.
qt6-imageformats supplies the missing plugin for 71 KB downloaded. Its
one new dependency of substance, libwebp, is already on every machine
by way of libvips.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
* Store theme backgrounds as webp
WebP codes both of the things these backgrounds are made of better than
the formats they were in: the photographs, where its lossy mode is worth
a third or more over JPEG at matched quality, and the flat art and dot
patterns, where its lossless mode undercuts an oxipng-packed PNG.
28 of them become lossless webp and decode bit-for-bit identically
(AE=0), so the dot patterns and flat-shaded pieces carry no quality
question at all. That includes 0-launch, whose alpha channel comes
through intact. The other 51 are photographs held to the same 38 dB
PSNR floor as the JPEG pass, landing between 38.0 and 54.6 dB. Every
image keeps its exact pixel dimensions, for 29.8 MB.
Each one is encoded from the original as it stands in quattro rather
than from the file the earlier commits produced, so nothing picks up a
second generation of loss on the way here.
13 stay JPEG. WebP is plainly larger for most of them, and three are
grainy enough that its filter smooths the grain instead of coding it:
PSNR plateaus near 34 dB however high the quality goes, well under the
floor.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
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Co-authored-by: Claude Opus 5 <noreply@anthropic.com>
* Re-encode over-encoded theme backgrounds
Several backgrounds shipped at quality 95-100, which buys nothing visible
on a wallpaper but costs 20 MB. Re-encode those at quality 85, leaving
resolution untouched -- every file keeps its original pixel dimensions.
Only files stored above quality 90 are touched, and only when the result
saves at least 15% and stays above 38 dB PSNR against the original. The
34 backgrounds already stored at quality 85 or below are left alone
rather than pushed through another lossy generation for a few hundred KB.
osaka-jade/2-shaded-entrance is skipped for that reason: nothing clears
both bars. ristretto/2-coffee-beans is re-encoded at 90 instead of 85,
where 85 fell below the PSNR floor.
Theme backgrounds drop from 107 MB to 87 MB.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
* Store nord's night-hawks background as a palette PNG
The file uses only 8 distinct colors but was saved as truecolor RGB,
costing 1.8 MB for an image an indexed palette stores in half the space.
Converting to a palette PNG is lossless: same dimensions, and zero pixels
differ from the original.
1782 KB -> 909 KB.
The other palette-eligible PNGs are already indexed, and re-compressing
them with ImageMagick only makes them bigger, so they are left alone.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
* Recompress theme PNGs losslessly with oxipng
Every background PNG was left at its authoring tool's default deflate
settings. Running oxipng over them re-packs the same pixels: all 31 files
decode bit-for-bit identically (AE=0) at unchanged resolution, for 981 KB.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
* Store photographic backgrounds as JPEG instead of PNG
Four backgrounds were shipped as PNG despite being photographs and
painterly illustrations, where lossless coding buys nothing the eye can
see. Re-encoding them at the same q85 used by the other backgrounds keeps
every pixel dimension and stays above 40 dB PSNR, for 3.3 MB.
The remaining PNGs stay PNG: JPEG is larger for the dot patterns and the
flat-shaded pieces, and 0-launch.png genuinely uses its alpha channel.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
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Co-authored-by: David Heinemeier Hansson <david@hey.com>
Co-authored-by: Claude Opus 5 <noreply@anthropic.com>
