This is a software package to measure deformation from images or frames from videos using Digital Image Correlation(DIC). Another capability is to create deformed images and videos using cairo. The package provides a command line interface which demonstrates the capabilities of measuring deformation from either images or videos and creating visualisations and storing the output in a csv file.
The deformeasure package relies on the following packages:
- Pillow
- numpy
- pycairo
- imageio
- matplotlib
- scipy
- pytest(optional)
To use the CLI provided with the package
- Clone from GitHub:
$ git clone https://github.com/SoftwareDevEngResearch/deformeasure
- Install the required version of dependencies:
$ pip install -r requirements.txt
- To install the package locally,
$ pip install /<PathToPackage>/deformeasure
OR
Install the package directly from GitHub via pip:
$ python -m pip install git+https://github.com/SoftwareDevEngResearch/deformeasure
To use the capability of creating deformed images or videos, run the creatng_deformation.py script in Functions directory:
- Run with default values:
$ cd /<PathToPackage>/deformeasure/Functions/
$ python3 creating_deformation.py
- To get help with input parameters:
$ cd /<PathToPackage>/deformeasure/Functions/
$ python3 creating_deformation.py --help
The transfromation matrix used to create deformed images:
| a1 | c3 | e5 |
|---|---|---|
| b2 | d4 | f6 |
| 0 | 0 | 1 |
Parameter description:
| parameter | type | description |
|---|---|---|
| image_size | int | Size of the generated reference and deformed images and videos |
| seed | int | Seed value for random generator |
| a1 | float | Scale in x direction |
| b2 | float | Shear in y direction |
| c3 | float | Shear in x direction |
| d4 | float | Scale in y direction |
| e5 | float | Translation in x direction |
| f6 | float | Translation in y direction |
| filename | string | name of the file with which the results will be stored in generated directory |
| mode | string | Option to generate deformed image or video |
Details of the functions can be accessed at /<PathtoPackage>/deformeasure/docs/build/html/index.html
Creating a video of deformation with 10% translation in x:
$ cd /<PathToPackage>/deformeasure/Functions/
$ python3 creating_deformation.py 50 19 1.0 0.1 0.0 1.0 0.0 0.0 example video
will create three files in /deformeasure/generated/video/def/
- def_example.gif (the deformation video)
- def_example_x.csv (deformations in pixels in x)
- def_example_y.csv (deformations in pixels in y)
and a reference image in /deformeasure/generated/video/ref/ ref_example.bmp
To measure deformation from images or videos, run the measuring_deformation.py script in Functions directory. This provides a CLI to use classes in Lib directory. To get help with the parameters:
$ cd /<PathToPackage>/deformeasure/Functions/
$ python3 measuring_deformation.py --help
The details of the parameters in CLI are:
| parameter | type | description |
|---|---|---|
| ref_image | string | location of the reference image |
| def_image | string | location of the deformed image |
| def_video | string | location of the deformation video |
| subset_size | int | Size of the subset(default=11) |
| initial_guess | list | Initial guess for deformations(default=[0.0,0.0]) |
| debug | bool | Use debug printing mode |
| output | string | name of the output csv file |
| visualize | bool | Option to visualize the deformations |
Measuring deformation from an image:
$ cd /<PathToPackage>/deformeasure/Functions/
$ python3 measuring_deformation.py -ri ../generated/image/ref/ref_translation_x.bmp -di ../generated/image/def/def_translation_x.bmp -v
Measuring deformation from a video:
$ cd /<PathToPackage>/deformeasure/Functions/
$ python3 measuring_deformation.py -ri ../generated/video/ref/ref_translation_x.bmp -dv ../generated/video/def/def_translation_x.gif -v
Once inside deformeasure, it can be tested by running pytest.
$ pytest
The source code used in measuring deformation were extended from PReDIC Github repository.