Uploading Images for OCR

Uploading your image or document correctly is the first and most important step in getting accurate OCR results. This guide walks you through everything you need to know to prepare and upload files effectively for fast, private, and reliable text recognition using our OCR platform.

1. Supported File Types

Our OCR platform supports a wide range of image and document file formats:

JPG and JPEG
PNG
GIF (static)
PDF (single-page only)
BMP and TIFF (where supported by browser)

We recommend using JPG or PNG for the best compatibility and performance.

2. How to Upload

Uploading a file is easy:

Click the “Upload” button or drag and drop your image into the designated area
Wait for the image to load in your browser (it is never uploaded to a server)
Once visible, proceed with the OCR process

3. Tips for Successful Uploads

Use clear, high-resolution images with good contrast
Make sure the text is not rotated or skewed
Crop unnecessary parts before uploading
Limit file size to under 5MB for best performance
Avoid multi-page PDFs; upload each page separately if needed

4. Privacy and Security

All uploads are processed entirely within your browser. Your files are:

Not sent to any server
Not stored, logged, or shared
Deleted from memory when you close the page

Conclusion

Uploading the right kind of image or document sets the foundation for high-quality OCR. Our browser-based platform ensures that your uploads remain private, secure, and processed instantly. With a few simple steps, you’re ready to convert your scanned documents into editable text.

Advanced Guide: Upload Workflow, Validation, and Troubleshooting

This in-depth guide clarifies how uploads work in the browser, the guardrails that lead to reliable OCR, and what to do when a file doesn’t behave. Everything here fits the current design: no server, no logins, and no hidden storage.

1) End-to-End Upload Flow

Select or drag-drop: Use the upload control or drop a file onto the page.
Decode locally: The browser decodes the image into pixels (no network transfer).
Preview & verify: Ensure the orientation, framing, and readability look right.
Run OCR: Kick off recognition when you’re satisfied with the preview.
Export or copy: Save text locally or copy to clipboard; close the tab to clear memory.

2) File Validation Rules That Help

Dimensions: Long edge under ~3000–4000 px is a good balance for speed and clarity.
Aspect ratio sanity: Extremely tall/long images (e.g., stitched screenshots) may need manual cropping into sections for best results.
Color space: Prefer sRGB; exotic profiles can shift contrast and reduce legibility.
Alpha/transparency: If a PNG has transparency, flatten on a white background before OCR to avoid washed glyph edges.
Animated formats: Use a static frame (GIF stills only); video is out of scope.

3) EXIF Orientation & Rotation

Some cameras save images “sideways” with an EXIF flag telling apps to rotate on display. If text looks rotated:

Rotate the image to the correct orientation before OCR, then re-upload.
For scans, ensure the page edges are parallel to the image borders (deskew if needed).

4) Single-Page PDF Handling

One page only: Multi-page PDFs should be split into individual pages before upload.
Vector text note: If a PDF actually contains selectable text (not a scan), exporting the page as an image (PNG/JPG) keeps behavior predictable.

5) Naming & Organization for Batches

Use consistent, sortable names such as YYYY-MM-DD_DocName_Pg-001.png.
Keep related pages in a single folder; process a couple of samples first to validate quality.

6) Accessibility & Keyboard Upload

The upload control is label-associated and focusable—use Enter/Space to open the file picker.
Screen reader users should hear the control’s purpose; progress belongs to an ARIA live region in the UI.

7) Privacy Preserving Habits

Review content before sharing exported text; redact personal identifiers where appropriate.
Avoid screenshots that include unrelated windows or notifications.
Close the tab when done to release memory.

8) Common Upload Errors & Fixes

“Unsupported file type”: Convert to PNG or high-quality JPG and try again.
“File too large” or slow preview: Downscale the long edge (≈2000–3000 px) or crop to the text region.
“Corrupted or cannot decode”: Re-save the image with an editor; damaged EXIF or color profile can break decoders.
“Looks fine but OCR is poor”: Increase contrast slightly, deskew, and ensure the x-height (lowercase height) is ~20–30 px after resizing.

9) Pre-Upload Checklist (Quick Wins)

Flat page, even lighting, no glare.
Crop to the actual text; remove borders and decorations.
Rotate upright; fix slight skew if lines aren’t horizontal.
Prefer PNG for screenshots/UI; JPG (300 DPI+) for scans.

10) Troubleshooting Decision Tree

Preview sideways? Rotate and re-upload → still skewed? Deskew by small degrees.
Text too small? Reshoot closer or upscale modestly; avoid heavy sharpening halos.
Glare or shadows? Change angle/lighting; a slight tilt often removes streaks.
Reading order wrong? Split columns/tables into separate uploads for precise control.

11) Do & Don’t (At a Glance)

Do: Use clear, high-contrast images; keep files moderate in size; check orientation.
Don’t: Upload low-res thumbnails, heavily compressed screenshots, or multi-page PDFs as a single file.

Summary

Reliable OCR starts with a clean, correctly oriented upload that the browser can decode quickly. Keep dimensions reasonable, prefer sRGB, split complex layouts into simpler parts, and verify the preview before you extract. These small steps make uploads predictable and results dependable—without changing how the app looks or works.