Compressionist

  • 3 Posts
  • 17 Comments
Joined 2 years ago
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Cake day: January 20th, 2023

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  • What about FOSS software is inherently jank? This is a stupid take that’s likely informed by some bad past experiences, of which I’ve had many with proprietary crapware.

    It is easier to find crap FOSS software because it is easier to make & maintain a FOSN project when you’re less competent & you don’t have a strategy for long term success. Proprietary software relies on for-profit motives to improve, while FOSS software relies on user feedback & community incentives. This is why, while the average quality of service from FOSS programs is potentially worse, the best QoS is usually from a FOSS program. See Elk for Mastodon for a fantastic example of premium quality.


  • If you look into it a bit more, the resistance around WebP is mainly because it has some crippling weaknesses. I did some visual quality testing ( here, here & here ) & I (as well as many others independently) have found that for photographic images, WebP & JPEG are equals, & Google’s messaging that lossy WebP meaningfully improves upon JPEG for general visual quality per bit is misleading. That being said, WebP has some important strengths that are not often acknowledged. In addition to transparency & (really good) animation support, it also has:

    • a lossless mode that often outperforms PNG
    • great nonphotographic compression (though AVIF outperforms it here)
    • decent compression of photographic sources at lower fidelity, where it actually starts to beat JPEG by a good amount
    • Totally royalty free

    WebP’s main weaknesses are:

    • not better than JPEG for photographic images at useful fidelity
    • Confusing messaging from Google, may have led to slow adoption
    • Based on a video codec, so no progressive decode (even JPEG has this)
    • limited to 8 BPC (lossy & lossless)
    • superseded by JPEG-XL & AVIF, which are both pretty much better at everything

    JPEG-XL in particular is very promising. It faces hostility from Google but has an incredible breadth of features & strong compression performance, as well as Apple ecosystem-wide adoption on the way with the upcoming versions of macOS, iOS, ipadOS, etc. It is also royalty free. AVIF is better than WebP at everything except lossless, too.

    Feeling any which way about WebP, it is still a shame to see it transcoded to PNG. All that wasted potential …