Scan to PDF Frequently Asked Questions

The Scan to PDF tool is an external module that allows you to scan documents using your device's camera and convert them to PDF format.

Key Features:

• Camera Capture: Use device camera (webcam or mobile) to photograph documents
• Multiple Pages: Capture multiple images for multi-page PDFs
• Live Preview: iframe shows captured images in real-time
• Reorder Pages: Drag-and-drop to rearrange captured pages
• jQuery UI: Interactive interface for managing scans
• External Module: Separate scanning component integrated into PDF Lab

Technical Implementation: The tool is an external module using HTML5 getUserMedia API to access device cameras. Users grant camera permission and capture photos of documents. Each capture is displayed in a live preview iframe. jQuery UI provides drag-and-drop reordering of captured pages. When ready, all images are converted to PDF using FPDI/TCPDF with each image becoming a page in the final PDF.

External module indicates that the Scan to PDF tool is a separate, specialized component integrated into PDF Lab.

What External Module Means:

• Separate Component: Not part of core PDF Lab codebase, but integrated as a plugin/module
• Own Interface: May have distinct UI design and workflow
• Independent Dependencies: Uses its own libraries (jQuery UI, camera APIs)
• Modular Architecture: Can be enabled/disabled independently

Benefits of External Module:

• Specialized Functionality: Focused on document scanning workflow
• Maintainability: Easier to update and maintain separately
• Optional Feature: Can be included or excluded based on needs
• Integration: Still seamlessly integrated with PDF Lab's file handling

Camera capture uses your device's built-in camera to photograph documents.

Camera Capture Process:

1. Grant Permission: Browser requests camera access, you grant permission
2. Camera Preview: Live camera feed appears on screen (video stream)
3. Position Document: Place document in camera view, ensure good lighting and alignment
4. Capture Photo: Click "Capture" button to take snapshot
5. Image Stored: Captured image added to scan queue
6. Repeat: For multi-page documents, repeat for each page
7. Generate PDF: When done, click "Create PDF" to convert all images to PDF

Technical Details:

• HTML5 getUserMedia API: navigator.mediaDevices.getUserMedia({ video: true })
• Video Stream: Live camera feed displayed in <video> element
• Canvas Capture: When capture button clicked, video frame copied to <canvas>
• Image Data: Canvas converted to base64 image (PNG or JPEG)

Camera Options:

• Desktop: Webcam (built-in or external)
• Mobile: Front camera or rear camera (typically better quality)
• Tablets: Built-in cameras on iPad, Android tablets

Yes! You can capture multiple images and compile them into a single multi-page PDF.

Multi-Page Scanning:

1. Capture First Page: Position page 1, click Capture
2. Capture Second Page: Position page 2, click Capture
3. Continue: Repeat for all pages (page 3, 4, 5, etc.)
4. Preview: All captured pages appear in live preview area
5. Reorder (if needed): Drag-and-drop pages to correct order
6. Create PDF: Click "Create PDF" button
7. Result: Single PDF with all captured pages in order

Page Management:

• Add Pages: Capture as many pages as needed (no limit)
• Reorder Pages: Drag thumbnails to rearrange order
• Delete Pages: Remove unwanted captures before PDF creation
• Review: Check all pages in preview before generating PDF

Use Cases:

• Scan 5-page contract 5-page PDF
• Scan 20-page report 20-page PDF
• Scan multi-page receipts, forms, or documents

The live preview iframe is a separate display area showing your captured images in real-time.

Live Preview Features:

• Real-Time Display: Captured images appear immediately after capture
• Thumbnail View: All captured pages shown as thumbnails
• Visual Feedback: See what you've scanned before generating PDF
• Page Order: Pages displayed in the order they'll appear in PDF

iframe Functionality:

• Separate Frame: Isolated HTML frame for preview content
• Interactive: Can interact with thumbnails (drag, delete)
• Drag-and-Drop: Reorder pages by dragging thumbnails
• Delete Button: Remove unwanted captures

Why Use iframe?

• Isolation: Preview UI separated from main scanning interface
• Performance: Better performance with many images
• Layout: Cleaner separation of capture and preview areas

Preview Workflow:

1. Capture image Image appears in iframe preview
2. Capture another Second image appears below first
3. Review all images in preview
4. Reorder or delete if needed
5. Create PDF when satisfied

jQuery UI is a JavaScript library providing interactive user interface components.

What is jQuery UI?

• Type: JavaScript UI library (built on jQuery)
• Purpose: Provides pre-built UI widgets and interactions
• Components: Drag-and-drop, dialogs, buttons, sliders, etc.
• Cross-Browser: Works consistently across all browsers

How Scan to PDF Uses jQuery UI:

• Drag-and-Drop (Sortable): Reorder captured page thumbnails
  • jQuery UI Sortable makes thumbnails draggable
  • Drag page 3 to position 1 to reorder
• Buttons: Styled capture and delete buttons
• Dialogs/Modals: Confirmation dialogs or help modals
• Visual Feedback: Smooth animations during interactions

Example jQuery UI Features in Action:

• Sortable: $("#page-list").sortable() enables drag-and-drop reordering
• Draggable Cursor: Cursor changes when hovering over draggable items
• Drop Zones: Visual indicators show where pages will drop
• Smooth Transitions: Animated movement when reordering

Yes, and it works especially well on mobile! Mobile devices have built-in cameras perfect for document scanning.

Mobile Scanning Advantages:

• Better Cameras: Mobile cameras (especially rear cameras) have higher quality than most webcams
• Portability: Scan documents anywhere, not just at your desk
• Auto-Focus: Mobile cameras have auto-focus for sharp document scans
• LED Flash: Use flash for better lighting in dark environments

Mobile Scanning Tips:

• Use Rear Camera: Better quality than front camera
• Good Lighting: Natural light or bright room lighting
• Flat Surface: Place document on flat surface for best results
• Steady Hands: Hold device still when capturing
• Landscape Mode: For landscape-oriented documents

Device Support:

• iOS: iPhone, iPad (Safari, Chrome)
• Android: Smartphones, tablets (Chrome, Firefox)
• Camera Permission: Grant camera access when prompted

No, we do not permanently store your scanned images or PDFs.

How We Handle Your Scans:

• Temporary Storage: Captured images stored in /tmp folder only during session
• PDF Generation: Images converted to PDF on-demand
• Automatic Cleanup: All temporary files deleted after download
• Session Isolation: Each user's scans isolated with unique session identifiers
• No Database Storage: Images and PDFs never saved to database

Privacy Guarantee:

• We do not access or view your scanned documents
• We do not permanently store scans
• All processing is temporary and secure

Security Measures:

• HTTPS encryption for all uploads and downloads
• Server-side processing without content inspection
• Temporary file cleanup after session

The output is a standard PDF file with each captured image as a page.

Output File Details:

• Filename: scanned_[timestamp].pdf
  • Example: scanned_20250116_165523.pdf
• PDF Version: PDF 1.7 or higher
• Page Structure: Each captured image = one PDF page
• Image Format: Images embedded as JPEG or PNG (depending on capture)
• Compatibility: Opens in all PDF readers

Image Quality:

• Depends on camera resolution and lighting
• Higher resolution cameras produce clearer scans
• Good lighting improves scan quality

The Scan to PDF tool combines camera APIs with PDF generation libraries.

Frontend Technologies:

• HTML5 getUserMedia API: Camera access
  • navigator.mediaDevices.getUserMedia({ video: true })
  • Requests camera permission and provides video stream
• HTML5 Canvas: Captures video frames as images
  • Video frame copied to canvas
  • canvas.toDataURL() converts to base64 image
• jQuery UI: Interactive UI components
  • Sortable for drag-and-drop page reordering
  • Buttons and dialogs for interface
• Live Preview iframe: Separate frame displaying captured images
• JavaScript: Image management and UI logic

Backend Technologies:

• FPDI/TCPDF: PDF generation from images
  • Each base64 image decoded and embedded as PDF page
  • Image() method for embedding
• Base64 Decoding: Converts base64 images to binary data
• Multi-Page PDF: Sequential page addition

Processing Workflow:

1. User grants camera permission
2. Camera stream displayed in video element
3. User clicks Capture video frame copied to canvas
4. Canvas converted to base64 image
5. Image added to preview iframe
6. Repeat for multiple pages
7. User can drag-and-drop to reorder pages
8. Click "Create PDF" all images sent to server
9. Server decodes base64 images and generates multi-page PDF
10. PDF downloaded to user

External Module Structure:

• Separate codebase integrated into PDF Lab
• Own dependencies (jQuery UI, camera APIs)
• Modular architecture for easy maintenance