Technical Specifications

Complete encoding guide, mark anatomy, data types, security modes, and implementation details for GF-Code technology.

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Mark Structure

Mark Anatomy

Every GF-Code mark consists of concentric zones radiating from the center, each serving a specific function in data encoding and detection.

[Mark Diagram]
Brand Well Center area for optional logo
Inner Quiet Zone Buffer between well and data
Format Ring 48-bit configuration header
Data Zone Waveform-encoded payload
Index Line Rotation reference at 12 o'clock
Outer Quiet Zone Boundary detection buffer

Encoding

Five Encoding Dimensions

Each spoke carries data through up to five independent channels, enabling 12-14 bits per spoke in full-color mode.

Dimension Bits Description Availability
Amplitude 2-3 Wave height (like volume in audio) All modes
Frequency 2-3 Oscillations per unit length All modes
Phase 1-2 Wave starting position offset All modes
Hue 3-4 Color selection from 20-color palette Chromatic only
Saturation 2-3 Color intensity levels Chromatic only

Header

48-Bit Format Ring

The Format Ring encodes mark configuration in 48 bits, read from the inner edge before data decoding begins.

Field Bits Purpose
Sync 2 Synchronization pattern
Version 4 Encoding version (0-15)
Security 1 Open (0) or Secured (1) mode
Mode 3 Color mode (Mono/Gray/Chromatic)
SpokeConfig 5 Number of spokes (4-32)
DataType 8 Payload type identifier
ECC 2 Error correction level
ExtFlag 1 Extended header flag
Reserved 14 Future use
Checksum 8 Header integrity check

Payloads

Supported Data Types

URL

Web addresses with optional prefix compression for common domains.

UUID

128-bit universally unique identifiers for product authentication.

Numeric ID

Compact integer encoding for SKUs, serial numbers, and IDs.

Plain Text

UTF-8 encoded text strings up to payload capacity.

vCard

Contact information in standard vCard format.

WiFi Config

Network credentials (SSID, password, encryption type).

JSON

Structured data payloads in JSON format.

Binary

Raw binary data for custom applications.

Security

Security Modes

Open Mode

Data can be freely read and copied. Ideal for URLs, payments, contact sharing, and public information distribution.

Secured Mode

Mark contains a UUID verified against an authenticated backend. Used for product authentication, anti-counterfeiting, and access control.

Capacity

Capacity Comparison

Technology Bits/Element Method
UPC Barcode 1 Binary (present/absent)
QR Code 1 Binary (black/white)
Data Matrix 1 Binary (black/white)
GF Monochrome 6-8 Amplitude + Frequency + Phase
GF Chromatic 12-14 All 5 dimensions