JXL Export and Photo-Based Event Day Boundaries · Release Candidates 57 and 58

JXL is now an export format

Aspect now links to libjxl 0.12.0, the reference implementation of the JPEG XL image format, and offers JXL as a choice in the export dialog alongside the existing formats.

JPEG XL is a royalty-free, ISO-standardized (ISO/IEC 18181) still-image format that is both lossy and lossless. It supports progressive decoding, alpha channels, ICC color profiles, and bit depths above 8 bits, which makes it suitable for the kinds of files photographers work with, not just web thumbnails. If you have not looked at the format before, see the JPEG XL site: jpegxl.dev.

Libjxl 0.12.0 is a substantial update to the codec (release notes). The changes most relevant to exporting:

• Smaller, faster lossless files. Progressive lossless images are now 30–40% smaller, and their encoding got multithreaded, which increases encoding performance by 2–5×. The "faster decoding" lossless modes are 30–80% smaller than before, which helps if you plan to display these files from disk without pre-decoding.
• Better gradient handling at lower bit depths. Dithering when decoding to fewer bits was switched from a Bayer matrix to a channel-offset blue noise pattern, which reduces banding in smooth skies and studio backgrounds — a visible improvement for the kind of imagery JXL export is commonly used for.
• A broad wave of fixes and hardening. Numerous SIMD speedups for the modular (lossless) path, improved EXR and color-management handling, and an extensive set of bug fixes and security hardening across the decoder.

Event day boundaries now follow the photos

When an event spans several days, Aspect divides it into calendar days, and that requires a time zone: 12:00 AM on "day two" means something different in Tokyo than in Amsterdam. Until now, the boundary was not determined by the photographs themselves, so an event could split differently depending on the device and time zone where the library was opened — noticeable on shared or traveling libraries, where the same event can be viewed from machines in different time zones.

This release changes how the time zone is selected: it is now derived from the majority of the photos in the event. In practical terms, a trip recorded over several time zones will consistently break into days according to where the shots were taken, regardless of which of your devices is showing the event. If you re-open events that contain photos from multiple time zones after updating, their day divisions may shift relative to before — that is intended behavior, not data being reorganized.

Crash fixes and smaller items

The remaining changes are fixes plus one usability improvement. The crash reporter can now display its log before you send it, so you can see what was reported or redact details before the log leaves the machine. We also fixed two crashes that had been coming in for a while: one that affected Intel Macs whenever a second window or dialog was shown, and one triggered when importing into a photo folder that the local library instance did not have. Both are resolved in this build; if you had been hitting either, this release should end it.

As always, see the change log for the full list of changes.

Release Candidate 58

A small update with three minor fixes has been released. See the change log for the full list of changes.