Straight lines for architecture. From any camera.
Meydn corrects perspective and lens distortion in photographs of buildings. Verticals stay vertical. Walls stop bending. Horizons sit level. Straighten the photos you have already taken in the web app, or correct live as you frame the shot in the app.
The problem you didn't know you had.
Look at any photo of a building you've taken. Walls lean inward. Doorways tilt. The horizon sits half a degree off. Corners bow outward like a fishbowl.
Three things mark a phone photo as a phone photo: converging verticals, barrel distortion, and an unlevel horizon. Once you can name them, you can't unsee them.
Professional photographers solve all three with $2,000 tilt-shift lenses and post-production. Meydn solves them at the moment you press the shutter.
Three corrections, applied live, every frame.
Tilt the phone up to fit a tall room or building, and the image keystones — parallel verticals converge toward the top of the frame.
Meydn computes a per-frame homography from the device's attitude and applies the inverse perspective transform live. Door frames stay rectangular. Buildings stand up.
The ultrawide lens is what makes interiors look open and exteriors look grand, but it bows straight lines near the edges.
Meydn corrects the distortion in real time using your iPhone's calibration data — so you get the dramatic framing without the fishbowl.
A horizon line that's half a degree off telegraphs handheld carelessness.
Roll is corrected automatically. No fussing with the level indicator, no fixing it in post.
Mathematics. Calibration. Silicon.
A 3×3 perspective homography per frame, derived from the gyroscope.
Lens distortion correction from Apple's per-device calibration.
Everything runs on the GPU, in real time.
Fully offline. Nothing leaves your device. No account, no cloud, no telemetry.Made for people who care how things stand up.
Inspired by Albrecht Meydenbauer.
In 1867, while measuring Wetzlar Cathedral from a scaffold, the Prussian architect Albrecht Meydenbauer nearly fell. Buildings, he decided, should not have to be climbed to be measured. He invented photogrammetry: extracting precise architectural geometry from photographs.
His method was simple. Keep the sensor plane parallel to the building, and the geometry stays honest. From his glass plates to tilt-shift lenses to Meydn on the device in your pocket, every architectural photograph whose verticals stay vertical descends from that idea.
Meydn is independent. Not affiliated with the Meydenbauer family or any institution.
Get Meydn for iPhone.
Always-on perspective and distortion correction. Fully offline. No subscription.
Download on the App Store