Case overview
PhotoSX is our own product: a native macOS application (Swift and SwiftUI) built for the least glamorous, most time-consuming part of professional photography — culling. After a wedding or an event you come home with thousands of RAW frames and one question repeated thousands of times: keep or not. PhotoSX is built to answer it in under 50 milliseconds per frame.
Involvement
- Native macOS App (Swift / SwiftUI)
- Image Pipeline Engineering
- Interface & Interaction Design
- Vision-Based Quality Analysis
- Localisation (4 languages)
The Brief
Existing culling tools decode RAW files to show you a frame, and RAW decoding is slow — so photographers wait, and waiting turns a two-hour job into an evening. The brief we set ourselves was simple and strict: frame changes under 50 ms, on real wedding-sized folders, on a laptop, without ever touching the original files.
- Under 50 ms per frame on real shoots
- Never write to or delete an original RAW
- Decisions that survive to the next day
Our Approach
The speed comes from refusing to do the expensive thing: PhotoSX reads the JPEG preview already embedded in every RAW file instead of demosaicing the sensor data.
Speed by architecture
Embedded preview reads, forward and backward prefetching, a 1.5 GB LRU cache and direct CALayer presentation. Measured at roughly 2.5 ms per frame uncached; on a cache hit a frame change costs a single layer assignment.
One-handed keyboard
Every decision key sits on the left of the keyboard — S to pick, X to reject, W for maybe, 1–5 for stars, colours on the number row — so your right hand stays on the mouse. Or the coffee.
Burst grouping that understands shooting
Frames are grouped by capture time and perceptual hash together, so a rapid-fire sequence groups but the same wall photographed two hours later does not. One key picks the keeper and rejects the rest of the series.
Vision analysis that flags, never deletes
Blur detection with a threshold derived from the session’s own distribution, plus closed-eye detection through face landmarks. Results are badges and counters — your decisions always outrank the machine’s.
The Results
PhotoSX is available now as a one-time licence, with no subscription.
Czech 
English