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chess-fen Chessboard Scanner

Instant 2D Diagram & 3D Camera Photo to FEN Recognition

Dual-Stream 2D/3D ONNX Vision • Sub-Pixel Homography • HiGHS MILP Constraint Solver

CPU ONNX Ready (p4_iter17-w1a-dual-u8, 14.37 MiB)
0 Logged Inferences
Cloud Mode (0 B Downloaded)

1. Capture or Upload Chessboard

Use phone camera, upload an image, paste from clipboard, or try a sample Snap a photo, upload an image, or tap a 1-click sample below

Drop a 3D chessboard photo or 2D diagram here, or press Ctrl+V to paste

Supports phone camera photos, screenshots, and digital chess diagrams (JPEG or PNG)

Raw image bytes, EXIF camera metadata, and (8, 8, 13) probabilities are logged automatically

Quick Demo Samples (1-Click Scan):

No Chessboard Loaded Yet

Click any Quick Demo Sample card above, drop an image, or press Ctrl+V

2. Recognized Position & FEN 2. Recognized Position, Diagnostics & Tuning Feedback

Click or use arrow keys on any square to adjust a piece, or drag pieces between squares Tap any square to inspect or edit its piece, or drag pieces between squares Select a demo sample or upload a photo
Ready to scan
White: 0 | Black: 0 | Total: 0
FEN & Analysis Links FIDE Legal
Castle:
Edit Square (a8) Entropy: — bits
Assign piece to selected square: Keys: Arrows P N B R Q K Del
Click any square on the board to inspect top-3 CNN probabilities
Inference & Solver Telemetry
Total Latency — ms
Mean Conf —%
Min Conf —%
MILP Repairs 0
Pre: —ms Detect: —ms Classify: —ms MILP: —ms

3. Telemetry Metrics & Future Tuning Dataset Ledger

All uploaded photos, (8, 8, 13) pre-solver probability tensors, corners, and user corrections are indexed for downstream training & MILP calibration
Logged Inferences / Unique Photos
0 / 0
3D Photos: 0 | 2D Diagrams: 0
CPU Latency (Mean / P95)
— / — ms
Det: —ms | Cls: —ms | MILP: —ms
Mean Confidence & MILP Repairs
—%
Repaired Boards: 0% (0 squares)
Verified Tuning Accuracy (Board / Square)
— / —
0 verified samples
Timestamp (UTC) Source Domain File / Camera Predicted / Verified FEN Conf (Mean / Min) Repairs Latency Tuning Status
No inferences logged yet. Click a Quick Demo Sample or upload a chessboard photo above.