@llamaindex/liteparse-wasm

Browser/WebAssembly build of LiteParse — a fast, lightweight PDF parser with spatial text extraction.

This package runs entirely in the browser. No server, no cloud calls.

Install

npm install @llamaindex/liteparse-wasm

Quick start

import init, { LiteParse } from "@llamaindex/liteparse-wasm";

// Load the wasm module (point at the file shipped with the package).
await init();

const parser = new LiteParse({
  ocrEnabled: false, // OCR requires a JS-side engine (see below)
  outputFormat: "json",
});

// `data` is a Uint8Array (e.g. from fetch / File / drag-drop).
const bytes = new Uint8Array(await file.arrayBuffer());
const result = await parser.parse(bytes);

console.log(result.text);          // full document text
console.log(result.pages[0]);      // per-page items with bboxes

Config options

All optional, camelCase:

| Option | Type | Default | Description | |---|---|---|---| | ocrLanguage | string | "eng" | Language code passed to the OCR engine | | ocrEnabled | boolean | true | Run OCR on text-sparse pages | | maxPages | number | 1000 | Stop after this many pages | | targetPages | string | — | e.g. "1-5,10,15-20" | | dpi | number | 150 | Render DPI for OCR / screenshots | | outputFormat | "json" \| "text" | "json" | Format used by parser.format(...) | | preserveVerySmallText | boolean | false | Keep tiny text that's normally filtered | | password | string | — | Password for protected PDFs | | quiet | boolean | false | Suppress progress logging | | ocrEngine | object | — | JS-side OCR engine (see below) |

OCR in the browser

The native HTTP-OCR and Tesseract backends are not available in the browser. To use OCR, pass an object with a recognize method:

const parser = new LiteParse({
  ocrEnabled: true,
  ocrLanguage: "eng",
  ocrEngine: {
    /**
     * @param imageData PNG-encoded image bytes
     * @param width  rendered page width  in pixels
     * @param height rendered page height in pixels
     * @param language e.g. "eng"
     * @returns array of { text, bbox: [x1,y1,x2,y2], confidence }
     */
    async recognize(imageData, width, height, language) {
      // e.g. call a worker that wraps tesseract.js, or a remote OCR service
      return [
        { text: "Hello", bbox: [10, 20, 80, 40], confidence: 0.98 },
      ];
    },
  },
});

Building from source

Requires Rust + wasm-pack:

# from packages/wasm
npm run build           # web target (default)
npm run build:bundler   # for webpack/rollup/vite
npm run build:nodejs    # for node.js

Output goes to pkg/.

Note: A real build also needs a static libpdfium.a compiled for wasm32-unknown-emscripten/wasm32-unknown-unknown exposed via PDFIUM_LIB_PATH. See the project root crates/WASM_PLAN.md for details.

License

Apache-2.0