Getting Started

Installation

Install afferent using your preferred package manager:

npm

npm install afferent

pnpm

pnpm add afferent

yarn

yarn add afferent

Basic Usage

Pass an array of OCR lines with coordinates [x, y, width, height, text] to processPageLayout:

import { processPageLayout, type OcrLine } from "afferent";

// Coordinates can be normalized (0..1) or pixel values
const lines: OcrLine[] = [
  { id: 1, text: "Platform License (Annual)", x: 0.08, y: 0.22, width: 0.45, height: 0.02 },
  { id: 2, text: "$12,000", x: 0.82, y: 0.221, width: 0.1, height: 0.02 },
  {
    id: 3,
    text: "Includes unlimited seats and priority support.",
    x: 0.08,
    y: 0.245,
    width: 0.55,
    height: 0.02,
  },
];

const page = await processPageLayout(lines);

console.log(page.itemBlocks);

Result Structure

processPageLayout returns a ProcessedPageLayout object containing:

• itemBlocks: Array of StitchedItemBlock items, each with title, description, value, price, box (bounding box union), and constituent lines.
• columns: Discovered column bands on the page.
• spanningLines: Full-width headers, footers, or disclaimer banners that span across columns.
• unassignedLines: Standalone lines not associated with any line-item block.