Derivative works — US Patent 5115326

Defensive Disclosure Document

Publication Date: April 29, 2026
Reference ID: DPD-2026-5115326
Title: Derivative Methods and Systems for Routing and Processing Image-Based Messages via Embedded Machine-Readable Metadata
Status: Publicly Disclosed

This document describes variations, extensions, and novel applications of the core methods disclosed in U.S. Patent 5,115,326, with the intent to place these concepts into the public domain and establish them as prior art.

Part 1: Derivatives of Fax-to-Network Routing via Embedded Code (Claims 1 & 9)

1.1. Material & Component Substitution

1.1.1. Digital Watermark Steganography for Routing

Enabling Description: A method where the network destination address is not visibly encoded but is embedded as a robust, low-frequency digital watermark within the luminance channel of the first page's scanned image. The encoding process utilizes a Discrete Cosine Transform (DCT) on 8x8 pixel blocks of the cover page image. The ASCII characters of the email address are converted to a binary string, which is then embedded into the low-to-mid frequency DCT coefficients of selected blocks. The receiving fax server performs a corresponding DCT analysis on the first page, extracts the binary string from the coefficients, reconstructs the address, and routes the message. This method is resilient to scaling, rotation, and lossy compression artifacts common in fax transmission.

Diagram:

sequenceDiagram
    participant Sender
    participant FaxServer as Fax Server (Gateway)
    participant Recipient

    Sender->>FaxServer: Transmits Fax (Page 1 with Watermark)
    activate FaxServer
    FaxServer->>FaxServer: Scan Page 1 Image Data
    FaxServer->>FaxServer: Perform DCT on Image Blocks
    FaxServer->>FaxServer: Extract Binary String from Coefficients
    FaxServer->>FaxServer: Reconstruct Network Address (e.g., email)
    FaxServer->>Recipient: Route Fax Image to Network Address
    deactivate FaxServer

1.1.2. Embedded RFID in Cover Sheet

Enabling Description: The cover sheet is manufactured with a passive, ultra-thin RFID tag (e.g., operating at 13.56 MHz, compliant with ISO/IEC 14443) embedded within the paper substrate. The destination network address is written to the tag's memory by a desktop RFID writer prior to sending. The document feeder of the receiving gateway is equipped with an RFID interrogator antenna. As the cover sheet is fed, the interrogator powers the tag and reads the stored address. This address is passed to the routing daemon, which then processes and forwards the subsequent scanned image data. This decouples routing information from the optical image, making it immune to smudges, poor print quality, or OCR errors.

Diagram:

graph TD
    A[Sender places document with RFID-embedded cover sheet in fax] --> B{Fax Gateway Paper Feeder};
    B -- Feeds Paper --> C[RFID Interrogator];
    C -- Powers & Reads Tag --> D[RFID Tag Memory];
    D -- "user@network.com" --> C;
    C -- Address Data --> E[Routing Daemon];
    B -- Scans Image --> E;
    E -- Packages and Sends --> F[Recipient on Network];

1.1.3. 2D Matricial Code for Enhanced Routing Data

Enabling Description: Instead of a 1D bar code, a 2D matricial code (e.g., QR Code or Data Matrix) is used on the cover page. This allows for encoding a structured data object, such as a JSON payload. The payload can include multiple recipients ("to": ["a@net.com", "b@net.com"]), a carbon copy list ("cc": [...]), a priority level ("priority": "high"), and a UUID for tracking ("uuid": "..."). The receiving server uses a 2D code library (e.g., ZXing) to scan the first page image, decode the matrix, parse the JSON object, and execute the complex routing logic defined therein.

Diagram:

classDiagram
  class EncodedDataObject {
    +to: string[]
    +cc: string[]
    +priority: string
    +uuid: string
    +subject: string
  }
  class FaxGateway {
    +receiveFax(image)
    -decodeQRCode(image) EncodedDataObject
    -parseRoutingJSON(data)
    -routeMessage(payload, image)
  }
  EncodedDataObject <.. FaxGateway : decodes to

1.2. Operational Parameter Expansion

1.2.1. Industrial Routing via Etched Codes on Metal Plates

Enabling Description: A method for routing quality control reports in an industrial foundry. Reports are etched or laser-marked as 2D Data Matrix codes directly onto thin metal plates accompanying a batch of materials. The "fax" is an imaging station that uses a structured light scanner or a laser profilometer to read the code, which is resistant to extreme heat (up to 500°C) and chemical exposure. The code contains the batch ID, material type, and the network address of the quality control database server. The imaging station transmits the image of the plate and the decoded routing data to a central server for archival.

Diagram:

flowchart LR
    subgraph Foundry Floor
        A[Material Batch] -- Accompanied by --> B(Metal Plate with Etched Code);
    end
    subgraph Imaging Station
        C{Structured Light Scanner} -- Reads --> B;
        C -- Decoded Data & Image --> D[Gateway Computer];
    end
    D -- Transmits to --> E((QC Database Server));

1.3. Cross-Domain Application

1.3.1. AgTech: Field Sample Routing

Enabling Description: In agricultural technology, soil and plant tissue samples are collected in the field. Each sample bag is affixed with a durable, weatherproof label containing a QR code. The code stores GPS coordinates, timestamp, sample type, and the ID for the target analysis workflow (e.g., 'nitrate_analysis_protocol_3'). At a mobile or central lab, the bag's label is scanned. The scanner captures an image of the label and transmits it to a LIMS (Laboratory Information Management System). The LIMS server decodes the QR code and uses the workflow ID to automatically assign the required tests and route the results to the correct farmer's account on the crop management platform.

Diagram:

sequenceDiagram
    participant Farmer
    participant FieldScanner as Field Lab Scanner
    participant LIMS_Server as LIMS Server
    participant CropPlatform as Crop Management Platform

    Farmer->>FieldScanner: Submits Sample Bag with QR Code Label
    activate FieldScanner
    FieldScanner->>LIMS_Server: Transmits image of label
    deactivate FieldScanner
    activate LIMS_Server
    LIMS_Server->>LIMS_Server: Decode QR (GPS, Timestamp, Workflow ID)
    LIMS_Server->>CropPlatform: Route analysis results based on ID
    activate CropPlatform
    CropPlatform->>Farmer: Display results on dashboard
    deactivate CropPlatform
    deactivate LIMS_Server

1.4. Integration with Emerging Tech

1.4.1. AI-Driven Dynamic Routing & Content Analysis

Enabling Description: The bar code on the cover sheet contains a basic recipient identifier (e.g., a corporate user ID). The receiving server decodes this ID and queries a real-time presence service (e.g., Microsoft Graph API) to check the recipient's status. Concurrently, it performs OCR and Natural Language Processing (NLP) on the fax content to determine its topic and urgency. An AI decision engine combines these inputs: if the content is an urgent legal summons and the recipient is on vacation, the engine reroutes the fax to the general counsel's office and sends an SMS alert. The routing rules are not static but are learned by a machine learning model based on historical routing decisions and outcomes.

Diagram:

graph TD
    A[Fax Received] --> B{Decode Barcode for User ID};
    A --> C{OCR & NLP on Fax Content};
    B --> D{Query Presence API};
    C --> E[Topic & Urgency];
    D --> F[User Status];
    subgraph AI_DecisionEngine as AI Decision Engine
        G((Combine: ID, Topic, Status));
    end
    E & F --> G;
    G --> H{Apply Learned Routing Policy};
    H --> I[Route to Optimal Destination];

1.4.2. Blockchain-Verified Immutable Transmission

Enabling Description: A method for transmitting legally binding documents. The sender first calculates a SHA-256 hash of the document image. They initiate a transaction on a private blockchain (e.g., Hyperledger Fabric) containing this hash, the recipient's public key, and a timestamp. The transaction ID is encoded into a QR code on the cover sheet. The receiver's gateway scans the QR code, queries the blockchain with the transaction ID to retrieve the original hash and recipient key. It re-calculates the hash of the received image and verifies it matches the one on the blockchain. If valid, it encrypts the document with the recipient's key before delivery, creating a tamper-proof, non-repudiable audit trail.

Diagram:

sequenceDiagram
    participant Sender
    participant Blockchain
    participant FaxGateway
    participant Recipient

    Sender->>Sender: Hash(Document) -> H1
    Sender->>Blockchain: Store {H1, Recipient_PubKey} -> TxID
    Sender->>FaxGateway: Send Fax with QR(TxID)
    activate FaxGateway
    FaxGateway->>FaxGateway: Decode QR -> TxID
    FaxGateway->>Blockchain: Query TxID -> {H1, Recipient_PubKey}
    FaxGateway->>FaxGateway: Hash(Received Image) -> H2
    alt Hashes Match (H1 == H2)
        FaxGateway->>FaxGateway: Encrypt(Image, Recipient_PubKey)
        FaxGateway->>Recipient: Deliver Encrypted Document
    else Hashes Mismatch
        FaxGateway->>Sender: Send Tamper Alert
    end
    deactivate FaxGateway

1.5. The "Inverse" or Failure Mode

1.5.1. Redacted Safe Mode Routing

Enabling Description: A system for environments handling PII, such as healthcare or finance. If the routing bar code is unreadable or fails checksum validation, the server assumes a high risk of mis-delivery. It automatically enters a "safe mode" where it performs full-page OCR and applies a regex-based redaction engine to identify and black-out patterns matching social security numbers, credit card numbers, patient IDs, etc. Only this redacted version of the fax is then forwarded to a human administrator in a secure "unroutable items" queue for manual processing, thus preventing accidental data exposure.

Diagram:

stateDiagram-v2
    [*] --> Receiving
    Receiving --> Decoding: Fax Arrives
    Decoding --> Routing: Barcode OK
    Routing --> [*]
    Decoding --> RedactionEngine: Barcode Read Failure
    RedactionEngine --> AdminQueue: Perform OCR & Redact PII
    AdminQueue --> [*]: Manual Review

Part 2: Derivatives of Document Orientation Detection (Claim 5)

2.1. Material & Component Substitution

2.1.1. Asymmetrical Digital Watermark

Enabling Description: An invisible digital watermark is embedded in the document image with a mathematically asymmetrical pattern. The decoding algorithm functions by attempting to correlate a key against the image data. The key itself is asymmetrical, meaning the correlation will only succeed with a high confidence score when the image is in its intended 0-degree orientation. The server attempts the correlation at 0, 90, 180, and 270 degrees. The orientation that produces the highest correlation score is determined to be the correct one, and the image is rotated accordingly.

Diagram:

flowchart TD
    A[Scan Image] --> B{Attempt Decode at 0°};
    B -- Fail --> C{Attempt Decode at 90°};
    C -- Fail --> D{Attempt Decode at 180°};
    D -- Fail --> E{Attempt Decode at 270°};
    B -- Success --> F[Set Orientation=0°];
    C -- Success --> G[Set Orientation=90°];
    D -- Success --> H[Set Orientation=180°];
    E -- Success --> I[Set Orientation=270°];
    F & G & H & I --> J[Rotate Image to Correct Orientation];

2.2. Integration with Emerging Tech

2.2.1. Unsupervised ML Model for Orientation

Enabling Description: A method that requires no special markings. A Convolutional Neural Network (CNN) is pre-trained on a large, unlabeled corpus of typical business documents. The model learns the general features of document layouts, such as the common locations of headers, footers, and the predominant direction of text flow. When a new fax is received, the image is passed through the CNN, which outputs a vector of probabilities for each of the four cardinal orientations (0, 90, 180, 270 degrees). The server rotates the image to the orientation with the highest probability before routing. This system can correctly orient legacy documents that lack any special codes.

Diagram:

graph LR
    A[Scanned Fax Image] --> B(CNN Model);
    B --> C["Output:
    P(0°)=0.95
    P(90°)=0.02
    P(180°)=0.02
    P(270°)=0.01"];
    C --> D{Select Max Probability};
    D -- "0°" --> E[Keep Original Orientation];

Part 3: Combination with Open-Source Standards

3.1. Integration with RFC 2301 (Internet Fax) and JSON Schema

Enabling Description: A system where the routing bar code on the fax cover page contains a Base64-encoded JSON object. The schema for this JSON object is published as an open standard (e.g., at schema.org/FaxRouting). The receiving gateway, compliant with RFC 2301 for creating email-based fax messages, decodes the barcode and the JSON. It then uses the key-value pairs from the JSON (e.g., to, subject, priority) to programmatically populate the corresponding MIME headers of the outgoing email message, ensuring interoperability between different vendors' fax server implementations that adhere to the public schema.

3.2. Integration with CUPS (Common UNIX Printing System) and Zint

Enabling Description: A CUPS print filter is created that intercepts print jobs directed to a "fax" printer. The filter script uses the open-source Zint barcode generation library to create a QR code containing the job's metadata (requesting user, destination number/email, timestamp). The script then uses ImageMagick to prepend the generated QR code image as a new first page to the original print job's PostScript or PDF file. The modified job is then passed to the physical fax modem backend. This allows any application printing through a standard CUPS server to generate compliant, routable faxes automatically.

3.3. Integration with ActivityPub Protocol for Decentralized Routing

Enabling Description: The bar code on the document contains a decentralized identifier compliant with the ActivityPub protocol (e.g., a user handle like @username@example.com). The receiving gateway acts as a federated server instance. Upon receiving and decoding the address, it OCRs the fax content to text. It then constructs a Create activity in ActivityPub format, with the OCR'd text as the content and the fax image as an attachment. This activity is posted to the outbox of a system actor, which federates the message to the destination user's instance. This allows faxes to be delivered directly and securely into decentralized social media or messaging platforms.