Why Apple Uses JPEG XL in the iPhone 16 and What It Means for Your Photos

Original Article ↗ Hacker News Discussion ↗

Significance of Apple adopting JPEG XL

  • Many see Apple’s move as a big inflection point for ecosystem adoption, though some argue Google/Chrome and Android support will still matter more for the web.
  • Using a common, royalty‑free standard (vs. Apple‑pushed formats) is viewed as a hopeful sign for broad, cross‑vendor uptake.
  • Some note Apple already added JPEG XL decoding in iOS 17/macOS 14; the iPhone 16 change is that it’s now in the camera pipeline (ProRAW).

Where and how Apple is using JPEG XL

  • JPEG XL is used inside DNG containers for ProRAW, replacing Lossless JPEG; regular photos still use HEIC.
  • JPEG XL is praised for high‑quality and lossless compression, higher bit depth than AVIF/HEIC in camera‑quality regimes, and good speed at practical settings.
  • JPEG XL itself isn’t a RAW container; DNG provides RAW metadata, JPEG XL provides the compression.

Environmental and efficiency debates

  • Some argue smaller cloud‑stored photos reduce energy and materials; others call this “whataboutism” and say storage energy is tiny compared to other emissions.
  • Several commenters assert compression/decompression cost is low, often less than transmission cost, and that better compression can even reduce decode energy.

Hardware, feature gating, and obsolescence

  • Confusion over why only iPhone 16 gets JXL in the camera; debate whether this is hardware‑acceleration driven or artificial feature gating to sell new phones.
  • Counterargument: older devices still work as before and already can view JPEG XL; “fake obsolescence” is contested.

Browser, OS, and ecosystem support

  • Chrome once had experimental JPEG XL and removed it; many hope Apple’s move will push Chrome and others to re‑enable it.
  • Firefox Nightly and some forks already have partial support; Windows 11 previews show hints of upcoming support.
  • Lack of universal browser support remains a blocker for using JPEG XL as a general web image format.

Tooling, migration, and web use

  • JPEG XL can losslessly recompress existing JPEGs and even be reversible back to the original JPEG; Linux tools exist, macOS tooling is missing.
  • Some argue there’s now no reason to serve legacy JPEG when JPEG XL is supported; others point out ecosystem and compatibility friction.

Comparisons to HEIC/AVIF and other formats

  • HEIC is a standard but was encumbered/licensed; JPEG XL is appreciated as royalty‑free and better for high‑quality and lossless use.
  • AVIF often wins at very low quality but is slower and worse at high‑fidelity/lossless; animated AVIF/WebP/APNG haven’t displaced GIF despite better tech.