FairScan

FairScan is an Android app to scan documents quickly, easily and privately.

It's designed to be simple: users get a clean, shareable PDF in seconds, with no manual adjustments. And respectful: open source, minimal permissions, no tracking, no ads.

• Website: https://fairscan.org
• Blog: https://fairscan.org/blog/

Contributing

Contributions are welcome, but please read the guidelines first: CONTRIBUTING.md

Translations

Translations are managed on Weblate, and everyone is welcome to contribute.

[Translation status]

Start translating: https://hosted.weblate.org/projects/fairscan/

Screenshots

Features

• Clear, distraction-free interface
• Easy flow: scan, review if needed, save or share
• Automatic document detection using a custom segmentation model
• Automatic perspective correction
• Automatic image enhancement
• Fast PDF generation with no manual adjustments
• All document processing happens locally on your device, no cloud processing
• Minimal permissions
• Open source, GPLv3

What FairScan is not

FairScan is not intended to:

• provide fine-grained manual control over document processing
• replicate all features found in other scanning apps
• optimize for highly specific use cases at the expense of simplicity

Compatibility

FairScan works on any device that:

• runs Android 8.0+
• has a camera

Experimental: Scan to PDF via intent

FairScan can be invoked by other Android applications to perform a document scan and return a generated PDF.

This feature is experimental and intended for developers who want to rely on FairScan as a simple, privacy-respecting scanning tool. The intent contract and behavior may change between versions, and backward compatibility is not guaranteed at this stage.

Intent action: org.fairscan.app.action.SCAN_TO_PDF

This is an implicit intent that launches FairScan in a dedicated external mode.

When started via this intent:

• FairScan opens directly in scan mode
• the user scans one or more pages
• FairScan generates a single PDF
• the resulting PDF is returned to the calling application as a URI with a limited lifetime
• the calling application should immediately copy the content of the URI as FairScan deletes it later

See an example app: fairscan-intent-sample

Technical details

FairScan uses:

• Jetpack Compose for the UI
• CameraX for image capture
• LiteRT to run the custom segmentation model for automatic document detection
• OpenCV for perspective correction and image enhancement
• Tesseract for text recognition (OCR)
• PDFBox-Android for PDF generation

The segmentation model

FairScan uses a custom-trained image segmentation model to detect documents: https://github.com/pynicolas/fairscan-segmentation-model

It's based on a fully public dataset that is available here: https://github.com/pynicolas/fairscan-dataset

The build system automatically downloads the model using
download-tflite.gradle.kts.

Related blog posts:

• Making document detection more reliable
• Building a public dataset for FairScan

Build

To build an APK:

./gradlew clean check assembleRelease

To build an Android App Bundle:

./gradlew clean check :app:bundleRelease

License

This project is licensed under the GNU GPLv3. See LICENSE for details.