QR ECC Inspector

Decode & visualize Reed-Solomon recovery

Input

Upload a QR code image. We'll decode it from scratch and report which ECC blocks were clean, corrected, or unrecoverable.

Grid Legend

Dark module

Light module

Function pattern

Corrected bit

Damaged (don't-care)

How it works

1. rqrr finds + samples the bit grid
2. Format info (BCH) → ECC level + mask
3. Read codewords in zig-zag, unmask
4. De-interleave into RS blocks
5. Berlekamp-Massey + Chien + Forney per block
6. Map flipped bits back to module positions

Upload a QR code or start the camera to begin.