QR contents
QR codes can contain coordinates, object names, notes, project parts or group information; group QR codes are therefore confidential.
QR data format
QR Import and QR Data Format
QR codes in ArxSilex MapTools are a versioned exchange format for compact app data. This page explains use, privacy and technical details.
Last updated: May 28, 2026
Summary
Overview for use and development
This section summarizes what QR codes contain, how they can be generated technically, and why import happens locally.
Technical compatibility
Custom tools can generate QR codes if they follow versioning, size limits, encoding and validation rules.
Local import
The link is not an upload. The server does not process the payload; the app reads the data locally from the QR link.
URL structure
The QR link
QR codes use a verified HTTPS app link. The data block is placed after the fragment sign.
https://www.arxsilex.de/app/maptools/qr#d=<base64url-json>
The part after # is normally not sent to the web server. The same link can therefore work as an app link and as a fallback to this explanation.
Privacy
Share confidentially
QR codes can contain coordinates, object names, notes, project parts or group information.
No automatic transfer
QR data is processed locally. This website does not decode or store the payload.
Geodata
Locations and project objects can be personal data. Share QR codes only with suitable recipients.
Groups
Group QR codes contain the group key. Anyone who scans the code can join the group or import group data.
Technical specification
Format status
Version 1 is currently documented. Newer versions can be rejected by older app versions.
| Item | Value | Notes |
|---|---|---|
| Current HTTPS app link | https://www.arxsilex.de/app/maptools/qr#d=<payload> | Path without trailing slash; this is how the Android app link is registered. |
| Documentation URL | https://www.arxsilex.de/app/maptools/qr/index.html | This web documentation is served as index.html in the QR folder. |
| Legacy scheme | asmaptools://qr?v=1&d=<payload> | Compatibility format for older or external scanners. |
| Payload encoding | Base64URL, UTF-8 JSON | URL-safe Base64 without padding; content is UTF-8 JSON. |
| Schema version | v: 1 | Versions below 1 are invalid; newer versions can be rejected. |
| Payload limit | 2,200 bytes | Conservative cap for reliable QR generation and decoding. |
| Incoming URI cap | 64 KiB | Hard upper bound for incoming deep links. |
| QR rendering | ZXing QR, error correction M, 512 px | The app renders 512 px QR bitmaps and may place a small app logo overlay. |
Schema
Compact object schema
Object QR codes use short keys to keep the QR code small. The keys themselves remain technical identifiers.
| Key | Meaning | Fields |
|---|---|---|
| v | Schema version | integer |
| m | Markers | i, n, inf, la, lo, ic, cl |
| c | Circles | i, n, la, lo, r, cl, sc, fc |
| d | Distances | i, n, la, lo, ea, eo, cl |
| b | Bearings/directions | i, n, la, lo, bg, ln, iv, bc, cl |
| a | Areas | i, n, pts, cl, sc, fc |
| r | Routes | i, n, pts, cl |
Groups
Typed group payloads
Group QR codes use typed JSON payloads. The group key is confidential.
type: group
Contains name, group_id, group_key, origin, color, description and optional quick messages.
type: objects
Wraps object data in an objects field.
type: group_with_objects
Combines group profile and optional objects. The app can import the group, the objects or both.
Validation
Validation and limits
The app checks QR data before import and rejects invalid geometry or oversized data.
Coordinates
Latitude -90 to 90, longitude -180 to 180. Exported coordinates are rounded to 5 decimals.
Geometry
IDs must be greater than 0. Routes need at least 2, areas at least 3 distinct points.
Bearings
Bearing 0 to 360 degrees, correction -180 to 180 degrees, length and interval at most 1,000 km.
JSON
Examples
Examples before Base64URL encoding. In the real QR link, encoded JSON is placed in #d=...
{
"v": 1,
"m": [
{"i":1,"n":"Start","la":48.13715,"lo":11.57612,"ic":"PIN"}
]
}{
"v": 1,
"type": "group",
"name": "Team Alpha",
"group_id": 123456,
"group_key": "shared-secret",
"originLat": 48.13715,
"originLon": 11.57612
}