About

Document Scanner is a sample application demonstrating the usage of CppBind tool. In this example, the tool allows the use of C++ OpenCV library in different platforms (iOS, Android), by generating wrappers over it. The application captures a photo using the phone camera and extracts a document from it. The original Document Scanner app is written in C++ and uses OpenCV.

This repository contains:

• CppBind-generated wrappers for functions and types from OpenCV used in Document Scanner for Kotlin, Python and Swift.
• apps with Document Scanner's functionality written in the languages listed above.

Repository structure

• document_scanner - contains the original library(under document_scanner_lib subdirectory) and the generated APIs for Android, iOS and Python.
• *cppbind.yaml, cv.yaml - CppBind configuration files.
• apps - directory containing the sample applications.
• CMakeLists.txt - cmake files.

To regenerate the bindings use cppbind run swift kotlin python command.

Running the applications

To build and run the sample applications, CMake and OpenCV should be installed.

To build the library run the following commands:

export OPENCV_DIR=<opencv_directory_here>
mkdir build_dir
cd build_dir
cmake .. 
cmake --build .
cd ..

To run the Python sample use the following commands

export PYTHONPATH=$PYTHONPATH:$(pwd)/document_scanner/api/python/generated/python:$(pwd)/build_dir/document_scanner/api/python
python3 apps/python/main.py data/img/paper.jpeg data/out

To compile and run the Kotlin sample use the following commands

Make sure Kotlin is installed and available on the path.

kotlinc document_scanner/api/android/docscanner/src/main/java/**/*.kt  apps/kotlin/main.kt  -include-runtime  -d apps/kotlin/libs/doc_scanner.jar                                        
kotlin -cp apps/kotlin/libs/doc_scanner.jar -Djava.library.path=build_dir/document_scanner/api/android/docscanner/src/main/cpp doc_scanner.DocumentScannerApp data/img/paper.jpeg data/out

To run the original sample in C++ use the following command:

build_dir/apps/document_scanner_app/document_scanner_app data/img/paper.jpeg data/out

You can also run the above commands with no arguments i.e. build_dir/document_scanner/cxx/document_scanner_app. In this case data/img/paper.jpeg will be used and the outputs will be saved in /tmp directory.

For running the Android sample see Android sample. For running the iOS sample see iOS sample