# jdt qr identity: random-address edition

Six new blue full-field marks open exactly
`https://tpofgo4e1fzht23d4a667qa7u0iq2jc3.jdt.engineering`.
Open [the gallery](gallery.html). The previous [identity collection](../brand-qr/gallery.html)
and all its existing paths remain unchanged.

The current mark is `variants/stack-v5/qr-90.png`, displayed at **90px**.
The matching SVG and 135px/360px PNG exports sit beside it. Each of the three
styles has a second independently solved variation. All six selected marks
use version 5-L: 37 modules plus the quiet zone, with no interior alignment
square. The 56-byte URL leaves 50 bytes of adjustable padding; version 4
would leave only 22 bytes for shaping the lettering.

The affine solver adjusts unused data bits and recalculates exact
Reed-Solomon parity. Every data-field target weight is positive. Smooth uses
82%-width data cells over the blue Panton target; structural cells and white
separators remain solid. There is no central image cutout or deliberately
damaged module.

96 candidates across versions 5 and 6 were evaluated. The final selection
uses the strongest two passing version-5 solutions per style. Each selected
mark passes independent matrix reconstruction, exact module-center and
structural-cell checks, and ZXing/OpenCV decoding at 90px, 135px and 360px,
plus 90px with 0.35px Gaussian blur. Candidates that did not pass remain in
[`candidates.zip`](candidates.zip); they are not presented as validated marks.
These digital checks do not guarantee scanning on every physical phone.

## Reproduce

Use the existing activated Python environment, preferably in a native WSL
work directory with the sibling `heading-qr-v3` solver and `patterns/fonts`.

```sh
source ../.venv/bin/activate
python src/prepare.py
esbuild src/generate.ts --bundle --platform=node --format=esm --outfile=src/generate.mjs
node src/generate.mjs
python src/validate.py
node src/gallery.mjs
```

The solver is shared with `heading-qr-v3/src/bit-field.ts`; its QR core is
MIT-licensed. Panton fonts retain their existing separate license.