Epipolar Consistency of X-Ray Images

Created by Andre Aichert (aaichert@gmail.com, andre.aichert@fau.de)

This project provides a GPU implementation in C++/CUDA of the Epipolar Consistency Metric. It relies on the Eigen 3 library and follows the 2016 CT-Meeting paper "Efficient Epipolar Consistency" by Aichert et al.

Please note that there is also a python-wrapped version of the ECC CUDA implementation in aaichert/xray-epipolar-consistency. It also contains a newer and more generic implementation of both FDTCMotionCorrection and FDCTCalibrationCorrection which still use the GPU for cost function evaluation.

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Prerequisites

The project uses a modern CMake build environment and requires:

• CMake (version >= 3.16)
• C++17 Compiler (GCC >= 8, MSVC >= 2019, or Clang)
• Qt6 (Components: Core, Gui, Widgets, Svg, PrintSupport, OpenGLWidgets, OpenGL)
• Eigen 3 (Header-only library, version >= 3.3.0)
• NLopt (Non-linear optimization library)
• CUDA Toolkit (Optional; required for GPU/CUDA backends)
• LibGetSet (Required for GUI tools, plot viewers, and property configuration panels)

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Dependency Setup: LibGetSet

Since this repository integrates with the LibGetSet properties configuration system, you will need to build and install it beforehand:

1. Clone the repository from aaichert/LibGetSet.
2. Configure, build, and install it to an install directory (e.g., <LibGetSet-source>/install).
3. Pass the path to this install directory to EpipolarConsistency via the CMake parameter -DGetSet_DIR=<path/to/LibGetSet/install>.

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Building and Running on Linux

1. Build Instructions

Create a build directory, configure the project with CMake, and build:

# Configure the build (set GetSet_DIR to the installation path of LibGetSet)
cmake -B build -S . \
  -DGetSet_DIR=/home/aaichert/nc_local/work/LibGetSet/install \
  -DCMAKE_INSTALL_RPATH="\$ORIGIN/../lib"

# Compile all enabled targets
cmake --build build -j$(nproc)

# Install files to a local directory (optional)
cmake --install build --prefix ./install

2. Running Instructions

From the Build Tree (Development)

During build-time, CMake configures the RPATH of the binaries automatically, allowing them to run directly without modifying library paths:

# Run the plot/nrrd viewer
./build/nrrdView/nrrdView

# Run the trajectory visualizer
./build/TrajectoryView/TrajectoryView

# Run the Radon intermediate visualizer
./build/VisualizeECC/VisualizeECC

From the Install Tree

If running the installed binaries (where RPATH may be stripped), make sure the dynamic linker can locate the shared libraries:

# Export the library path
export LD_LIBRARY_PATH=/path/to/install/lib:$LD_LIBRARY_PATH

# Run the binary
/path/to/install/bin/nrrdView

Recommended Working Directory

We recommend running all tools with their working directory set to config/. This keeps generated .ini property files, logs, and temp configurations organized:

cd config
../build/nrrdView/nrrdView

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Building and Running on Windows

1. Build Instructions (Visual Studio / MSBuild)

Use CMake to generate Visual Studio solution files or build directly from the command line:

:: Configure the project (set GetSet_DIR to your LibGetSet install path)
cmake -B build -S . -DGetSet_DIR=C:/Development/extern/GetSet

:: Build the project in Release configuration
cmake --build build --config Release

:: Install the project files (optional)
cmake --install build --prefix C:/Development/export/EpipolarConsistency --config Release

If you prefer a graphical interface, run the CMake GUI, specify the source directory and a build directory, configure (using Visual Studio 2019/2022 generator), set the required directory variables (such as GetSet_DIR and Eigen3_DIR), and click Generate. Open the generated EpipolarConsistency.sln solution file in Visual Studio.

2. Running Instructions

To run the executables on Windows:

• Ensure that the Qt6 DLLs, CUDA runtime DLLs, and LibGetSet DLLs are in your system's PATH, or copy them into the directory containing your executables (e.g., build/bin/Release or install/bin).
• Set your working directory to the ./config folder to keep your environment tidy.