PDF to Image Showcase Demo Code Sample

Requirements

These packages are required to use these features in production. Trial keys have unlimited access to all features

Web SDKLive demo

Easily convert PDFs to images like JPG or PNG, completely on the client side, with no server needed.

This demo allows you to:

• Upload your own PDF file
• Add annotations
• Convert the PDF's first page into an image
• Download the image

Implementation steps To add form fields to a PDF with WebViewer:

Step 1: Choose your preferred web stack Step 2: Add the ES6 JavaScript sample code provided in this guide

This demo converts only the first page of the PDF.

Once you generate your license key, it will automatically be included in your sample code below.

// ES6 Compliant Syntax
// GitHub Copilot v1, Claude Sonnet 3.5, 2025-07-31
// File: pdf-to-image/index.js
 
import WebViewer from '@pdftron/webviewer';
import { saveAs } from 'file-saver';

const licenseKey = 'YOUR_WEBVIEWER_LICENSE_KEY';

// List of supported image formats
 const imageFormats = [ 'jpeg', 'png'];

const element = document.getElementById('viewer');
let theInstance = null;
const onLoad = async (instance) => {
  theInstance = instance;
  instance.Core.documentViewer.addEventListener('documentLoaded', () => {
    toDownload = null; // reset download state
    buttonDownload.style.display = 'none'; // hide download button when uploading new file
  });
};

// Initialize WebViewer and load default document
WebViewer(
  {
    path: '/lib',
    licenseKey: licenseKey, 
    initialDoc: 'https://apryse.s3.amazonaws.com/public/files/samples/WebviewerDemoDoc.pdf',
    enableFilePicker: true, // Enable file picker to open files. In WebViewer -> menu icon -> Open File
  },
  element
).then((instance) => {
  onLoad(instance);
});

let toDownload = null;

const buttonDownload = document.createElement('button');
buttonDownload.textContent = '';
buttonDownload.style.display = 'none'; // initially hide the download button
buttonDownload.onclick = async () => {
  if (toDownload) {
    const { blob, newFileName } = toDownload;
    saveAs(blob, newFileName);
  }
};

// Function to convert the current document to an image
// If the document has more than one page, it will convert the current page only
const convertToImage = async (format) => {
    const docViewer = theInstance.Core.documentViewer;
  const doc = docViewer.getDocument();
  const oldFileName = doc.getFilename();

  const newFileName = oldFileName.substring(0, oldFileName.lastIndexOf('.')) + '.' + format;
  console.log('Converting to:', newFileName);
  const pageNumber = docViewer.getCurrentPage();
  console.log('Current page:', pageNumber);
  const zoom = 2; // render at twice the resolution
  
  doc.loadCanvas({
    pageNumber,
    zoom,
    drawComplete: async (imageCanvas) => {
      const corePageRotation = (doc.getPageRotation(pageNumber) / 90) % 4;
      const annManager = docViewer.getAnnotationManager()
      annManager.setAnnotationCanvasTransform(imageCanvas.getContext('2d'), zoom, corePageRotation);

      // optionally comment out "drawAnnotations" below to exclude annotations
      await annManager.drawAnnotations(pageNumber, imageCanvas);
      imageCanvas.toBlob(function (blob) {
          toDownload = { blob, newFileName };
        }, 'image/' + format);
      buttonDownload.style.display = 'inline'; // show download button after conversion
      buttonDownload.textContent = newFileName + ' ⭳';
    }
  });
}

// Create a button to convert the current document to an image
const buttonConvert = document.createElement('button');
buttonConvert.textContent = 'Convert';
buttonConvert.onclick = async () => {
  const format = imageFormatSelect.value; // Get the selected image format
  await convertToImage(format);
};

// Create a dropdown for image formats
const imageFormatSelect = document.createElement('select');

// Populate the dropdown with options
imageFormats.forEach(format => {
  const option = document.createElement('option');
  option.value = format; // Use the format as the value
  option.textContent = format.toUpperCase(); // Display the format in uppercase
  imageFormatSelect.appendChild(option);
});

// set default value for the dropdown
imageFormatSelect.value = imageFormats[0]; // Default to first format
imageFormatSelect.onchange = () => {
  // Hide the download button when changing format
  buttonDownload.style.display = 'none';
  toDownload = null; // reset download state
};
const convertLabel = document.createElement('label');
convertLabel.textContent = 'Use the Open File command in the WebViewer UI menu to upload a PDF, then select image format: ';

// UI section
//
// Helper code to add controls to the viewer holding the buttons and dropdown

// Create a container for all controls (label, dropdown, and buttons)
const controlsContainer = document.createElement('div');

// Apply classes for styling using CSS
convertLabel.className = 'label-class';
buttonConvert.className = 'btn-style';
buttonDownload.className = 'btn-style';
imageFormatSelect.className = 'select-style';
controlsContainer.className = 'control-container';

// Append elements to the controls container
controlsContainer.appendChild(convertLabel);
controlsContainer.appendChild(imageFormatSelect);
controlsContainer.appendChild(buttonConvert);
controlsContainer.appendChild(buttonDownload);
element.insertBefore(controlsContainer, element.firstChild);

View the full sample on GitHub