Stepframe: an analog round-trip filmmaking pipeline breakdown
Stepframe turns a digital video into printable contact sheets you photograph or manipulate on film, then reassembles the scans back into a video — preserving every analog imperfection the medium introduces along the way.
- Extract
- Contact Sheets
- Print & Modify
- Reassemble
Extract
Stepframe opens the source video and pulls every frame at your chosen FPS — the raw material for the print run.
Contact Sheets
ArUco marker
Corner fiducials the scanner uses to find and de-warp the sheet's four corners, correcting for the angle you photographed it at.
QR code
Encodes the sheet's identity and frame layout, so the reassembler knows which frames these are and their order.
Frames are laid out on print-ready contact sheets, each corner carrying an ArUco fiducial marker and a QR code that encodes the frame offset, FPS, page format, and the video's aspect ratio. The QR + ArUco system tolerates rotation and mild perspective distortion; if a sheet's own QR code is unreadable, Stepframe falls back to the configuration decoded from adjacent sheets.
Print & Modify
From here it leaves the computer entirely. Users print their contact sheets, then draw on them, paint them, burn, tear, photocopy, or shoot them on film — whatever marks the analog world leaves are the point.
Reassemble
Scanned sheets go back through the same ArUco + QR system: the markers locate each sheet, the QR payload tells Stepframe which frames live where, and the cells are extracted — echoing stage 1, now carrying whatever the analog round trip did to them. The frames snap back into their original sequence, reassembled into a new video that keeps every imperfection the process introduced.