Interactive Image Cropper Studio
Supports PNG, JPG, WebP, GIF, BMP, SVG. Processed 100% locally inside your browser.
About Image Perspective Cropper
The 4-Point Perspective & Document Deskewing Tool straightens angled document scans, whiteboard photos, and receipt photos using 4-corner homography matrix warping, outputting flat rectangular scans directly in your browser.
How to Use Image Perspective Cropper
Step 1
Upload an angled photo of a document, receipt, or whiteboard.
Step 2
Drag the 4 corner handles to match the corners of the paper document.
Step 3
Review the straightened preview image.
Step 4
Click "Download Straightened Image".
Practical Use Cases for Image Perspective Cropper
Flattening Angled Document & Receipt Photos
Transform keystone-distorted smartphone photos of paper receipts, contracts, and business cards into clean flat 2D rectangular documents.
Straightening Whiteboard Notes from Meeting Angles
Deskew photos taken from the side of a meeting conference room into a front-facing rectangular whiteboard image.
Input & Output Examples
Deskewing Angled Paper Document
4 Corners: `TL(120,80), TR(780,110), BR(740,560), BL(80,520)`
Flat, rectilinear 800x600 rectangular document scan with corrected perspective
Key Features & Performance
- ✓Interactive 4-point draggable corner pins with magnifying loupe for micro-precision alignment.
- ✓Computes $3 \times 3$ projective homography matrix with bilinear pixel interpolation.
- ✓Document auto-enhancement filters: High-Contrast Black & White, Text Sharpen, Grayscale Scan.
- ✓100% Client-Side projective transformation engine.
- ✓1-Click Download deskewed image or PDF.
Key Terminology & Definitions
Perspective Homography
A mathematical transformation mapping points between two planar projections, correcting perspective distortion caused by camera angle.
Bilinear Interpolation
An image resampling algorithm that samples the four nearest pixels to calculate smooth pixel values in warped coordinate spaces.