IPASC Standardised Image Reconstruction Project

Code repository for the IPASC standardised image reconstruction project

The project is divided into three tasks:

• Data generation and collection
• Implementation of reconstruction algorithms
• Development of an evaluation framework

Each of these tasks has one module in this repository where the code is collected. How these modules are intended to be used is described in the following sections:

Getting Started

0. Install git and python3 for your platform.
1. Clone the repository with git clone https://github.com/IPASC/standardised-image-reconstruction.git.
2. Enter the directory: cd standardised-image-reconstruction (Linux and Mac).
3. Optional Create a virtual environment with python3 -m venv env and enter it with source env/bin/activate (Linux and Mac).
4. Install dependencies pip install -r requirements.txt
5. Make sure everything works by running python3 run_all.py

Data Generation

Simulated Data

This part describes the steps that need to be done in order to simulate the virtual phantoms used for this project.

Prerequisites

Do run the data modelling, you will have to manually download both the SIMPA and the PACFISH GitHub repositories. These folders have to be located within the same parent folder on your hard drive, because of the way the code is currently set up. Please see and follow the SIMPA and PACFISH install instructions on their respective GitHub pages.

Optical Modelling

Optical modelling is optional. If you want to use optical modelling, you can use the pre-implemented simulation module in SIMPA that uses Monte Carlo eXtreme, maintained by Qianqian Fang.

MCX requires the availability of an NVIDIA GPU on your computer. You can download pre-compiled binaries fitting your system, or compile mcx yourself from the source code here.

Acoustic Modelling

For the acoustic forward model, we are using k-Wave (http://k-wave.org/). A base script for the simulation can be found at data_generation/base_script/. The contained scripts are meant to be used as a guide to facilitate setting up a k-Wave simulation on a new data set.

The script also enables a data export into the IPASC data format. To enable this feature, the latest version of the PACFISH tool needs to be downloaded and the path to the PATH/TO/PACFISH/pacfish_matlab folder has to be added as an absolute path to the MATLAB paths (please adjust the path based on where the folder is on your computer).

Please download the pacfish tool from github (https://github.com/IPASC/PACFISH/):

git clone https://github.com/IPASC/PACFISH/

The resulting data should in the end be uploaded to the IPASC Google Drive using this link: https://drive.google.com/drive/folders/19ZnxzWITQl7K9sCQsF1TxYfChYMYSs89

Experimental Data

TODO

Image Reconstruction

Each algorithm implementation should be done in a separate class that inherits from the ReconstructionAlgorithm base class defined in image_reconstruction.__init__.py. The BaselineDelayAndSumAlgorithm can be used as a reference.

There exists a test base class that automatically downloads sample_data in the IPASC format such that the algorithm implementation can easily be tested. Please refer to the test_baseline_delay_and_sum.py file for a coding reference.

Quality Assessment

TODO

Contribute to the project

Please see the CONTRIBUTING.md file for information on how to contribute.

Known Issues

• The path_config.env files need the full path. ~ signs for the home directory as commonly used on Linux systems do not work.

• MATLAB 2017b and earlier isn’t (yet) supported.

• If you have problems with SSL-certificate issues when using Anaconda, please add the following paths to your PATH environment variables:

  path/to/Anaconda3
  path/to/Scripts
  path/to/Anaconda3/Library
  path/to/Anaconda3/Library/Bin
  

  • Then run this command from your Anaconda terminal:

    python -m pip install --upgrade pip

Frequently Asked Questions

What types of transducers are currently supported by the project?

The project focuses on linear array transducers at this point in time. In the future, we hope to extend support of the project to other transducer designs as well.

The project dependencies cannot be installed/found. How can I set up the project correctly?

Not all dependencies may be installable with your package manager of choice. For example, it is not possible to directly install the SIMPA project with Anaconda. SIMPA is distributed via pypi and can be installed with the pip package manager.

This is the preferred workflow for setting up the dependencies:

1. Set up a new virtual environment (python -m venv venv)
2. Activate the virtual environment (linux: source venv/bin/activate, windows: venv/Scripts/activate.bat)
3. Install all dependencies using (pip install -r requirements.txt)
4. Configure your IDE to use the venv virtual environment (The name venv can be replaced by any name you like)

Citations

FFT-Based Jaeger

• Jaeger, M., Schüpbach, S., Gertsch, A., Kitz, M., & Frenz, M. (2007). Fourier reconstruction in optoacoustic imaging using truncated regularized inverse k-space interpolation. Inverse Problems, 23(6), S51.

FFT-Based Hauptmann

• Hauptmann, A., Cox, B., Lucka, F., Huynh, N., Betcke, M., Beard, P., & Arridge, S. (2018, September). Approximate k-space models and deep learning for fast photoacoustic reconstruction. In International Workshop on Machine Learning for Medical Image Reconstruction (pp. 103-111). Springer, Cham.

• Köstli, K. P., Frenz, M., Bebie, H., & Weber, H. P. (2001). Temporal backward projection of optoacoustic pressure transients using Fourier transform methods. Physics in Medicine & Biology, 46(7), 1863.

• Xu, Y., Feng, D., & Wang, L. V. (2002). Exact frequency-domain reconstruction for thermoacoustic tomography. I. Planar geometry. IEEE transactions on medical imaging, 21(7), 823-828.

Back Projection

• Xu, M., & Wang, L. V. (2005). Universal back-projection algorithm for photoacoustic computed tomography. Physical Review E, 71(1), 016706.

Delay-Multiply-and-Sum

• Matrone, Giulia, Alessandro Stuart Savoia, Giosuè Caliano, and Giovanni Magenes. "The delay multiply and sum beamforming algorithm in ultrasound B-mode medical imaging." IEEE transactions on medical imaging 34, no. 4 (2014): 940-949.