Deskew (auto-straighten)

POST /api/image-deskew

Auto-deskew a scanned document. Detects the rotation angle (up to ±15°) and rotates the image so text lines are horizontal. Useful before OCR.

Detects the rotation angle of a scanned document (up to ±15°) and rotates it so the text lines are horizontal. Useful before feeding scans into `document-ocr`. The detection is based on edge analysis, so it works best on text-heavy documents. Photos and screenshots may not have a meaningful skew angle to detect.

Inputs

Name	Type	Default	Description
image*	file	—	Input image bytes.
background	string	"white"	Background fill colour for rotated regions outside the original (CSS-style hex or named: white, black, transparent).
maxAngle	number (0…90)	45	Cap rotation magnitude — angles outside ±maxAngle are rejected (likely false positives).

Response

Modes: binary, json. Cache: yes (24h TTL).