Help & Support Center

CamMaster uses OpenCV.js, a browser-native computer vision library, to analyze your uploaded image. It applies Canny edge detection and contour finding to locate the largest quadrilateral in the image — which is usually the document. It then automatically sets the 4 corner handles to match the detected edges. You can drag any corner to fine-tune the selection.

When you photograph a document from an angle, it appears tilted. Perspective warp takes the 4 corner points you've set and mathematically transforms the image so the document appears as if photographed straight from directly above — flat, square, and correctly proportioned. This is also called "deskewing" or "perspective correction."

• Original — No filter applied
• Auto-Enhance — Boosts contrast and sharpness automatically
• Magic Pro (AI) — Deep shadow removal + aggressive sharpening, best for photos of documents
• Lighten — Brightens the image
• No Shadow — Removes paper shadows using local contrast normalization
• Black & White — High contrast binary black/white, ideal for text documents
• B&W Soft — Softer black and white with gray tones
• Grayscale — Classic grayscale without contrast boost
• Eco Print — Reduces ink usage by lightening the image slightly

Yes! After processing your first page through the crop and filter steps, you'll arrive at the Pages screen. From there, you can click "Add More" to upload additional images or PDFs. All pages can be reordered by dragging. When you're ready, go to the Export screen to download as a single multi-page PDF.

Edge detection works best when there is good contrast between the document and the background. Try: (1) Place the document on a dark, non-reflective surface. (2) Ensure good, even lighting. (3) If detection still fails, manually drag the corner handles to the document's corners and click "Apply Crop" manually.

In the Merge PDF tool, after you add your PDF files, each file appears as a card with numbered page checkboxes. Click individual page numbers to toggle them (highlighted = selected, grey = excluded). Use the All / None buttons for quick selection, or click Range… to type a range like "1-3, 5, 8-10". Only checked pages will be included in the merged output.

In the Split PDF tool, upload your PDF and select the Visual Split mode. Your PDF pages will appear as thumbnails. Between each pair of pages, you'll see a ✂️ split here divider. Click a divider to activate it (it turns red). You can activate multiple dividers to create multiple output parts. Then click "Split PDF" to download a ZIP containing all the parts.

Image to PDF accepts JPG, JPEG, PNG, and WEBP files. You can add multiple images at once and they'll each become a page in the PDF. The page size, orientation, margin, and JPEG quality are all configurable before generating.

OCR accuracy depends on image quality. For best results: (1) Use a clear, high-resolution image — at least 150 DPI. (2) Ensure the text is not blurry or at a steep angle. (3) Select the correct language from the dropdown. (4) Consider using the scanner's "Auto-Enhance" or "Magic Pro" filter before running OCR to improve text clarity.

The Compress tool works on individual images (JPG, PNG, WEBP). To reduce a PDF's file size, use PDF to JPG to extract the pages, compress each image, then use Image to PDF to re-combine them. Direct PDF re-compression (changing internal PDF compression) is planned for a future update.

There is no hard file size limit — it depends on your device's available RAM. Modern browsers can handle PDFs up to 100+ MB without issues. Very large files (500MB+) may cause slow processing or browser memory warnings on lower-end devices.

No. All file processing in CamMaster happens entirely inside your browser using JavaScript. Your files never leave your device. PDFdukan's servers only serve the HTML, CSS, and JavaScript files needed to run the application — they never receive your document data.

PDFdukan stores nothing on our servers unless you sign in with Google. Locally (on your own device), we save: your theme preference, application settings, and a list of recent document names. No file content is ever stored anywhere. See our full Privacy Policy.

Go to your browser's privacy settings to remove all saved recent documents. To clear all CamMaster data from your browser, clear the localStorage for pdfdukan.com in your browser's developer tools, or use your browser's "Clear Site Data" option in site settings.

Yes. Because all processing happens locally, your sensitive documents (ID cards, contracts, financial statements) are never exposed to any third-party server. That said, be mindful of your device's security — use a device you trust and lock it when not in use.

No. All basic features are available without signing in. Google Sign-In is optional and enables additional features like saving to Google Drive and syncing settings across devices.

When signed in with Google, you can: (1) Save processed documents directly to your Google Drive, (2) Access your recent documents from any device, (3) Sync your settings across devices. Google Sign-In is currently in development and will be available soon.

Click your name or the "Sign In" button in the top-right corner of any page. A dialog will appear asking if you'd like to sign out. Confirm to sign out and clear your account session from this device.