About this Project

This project is being developed as a practical part of bachelor's thesis at Brno Universtiy of Technology - Faculty of Information Studies. It is as of now a work in progress, no results guaranteed.

The topic of this thesis is Generating a 3D Fingerprint Model. This application can be used to apply series of image processing filters to a fingerprint image to make it more suitable for conversion to 3D stl model and printing. It also includes the functionality to use generated image as a height map for generating an stl model. This model can either be planar or curved.

Prerequisites

For now this is only viable for ubuntu gnu/linux machines Before cloning repository, you need these to succesfully use the application.

• python version 3.10 is a requirement might work on earlier python 3 versions

      sudo apt install python3.10
  

• virtualenv for virtual enviroment creation

      pip install virtualenv
  

Installation

1. Go to a suitable installation folder, for example Documents.

       cd /home/username/Documents
   

2. Clone the repository to a suitable directory, for example

       git clone ssh://git@strade.fit.vutbr.cz:3022/xlanro00/BP_DP-xlanro00.git
   

3. Go inside cloned directory

       cd BP_DP-xlanro00
   

v 4. Create and enter the virtual enviroment. sh virtualenv .venv && source .venv/bin/activate

5. Install required python modules from requirements.txt.

       pip install -r requirements.txt
   

6. Run the application, as an example there is a file in res/examples called Palec_P4.tif. This is shown in the section below.

Filtering images

Once all the requirements are installed, the program is ready to use. There are two ways to enter the filters:

1. manually list filter names and parameters from command line

       python3 src/main.py res/examples/Palec_P4.tif res/examples/Palec_P4.png 600 denoise_tv_chambolle iterations=1 weight=0.2 median ksize=5
   

2. from preset saved in a json config file, that can be used to tune and modify existing presetrs, or create new ones

       python3 src/main.py res/examples/Palec_P4.tif res/examples/Palec_P4_from_preset.png 600 --config config/config.json git_example
   

Configuration and presets

There is an option to input the filter series as a preset from json configuration file.

{
    "preset": [
        {
            "name": "filter_name",
            "parameter": value,
            "parameter": value
        },
        {
            "name": "filter_name",
            "parameter": value
        }
    ],
    "preset": [
        ...
    ]
    ...
}

For example

{
    "git_example": [
        {
            "name": "denoise_tv_chambolle",
            "weight": 0.01,
            "iterations": 1
        },
        {
            "name": "median",
            "ksize": 3
        }
    ]
}

All the filters used and their parameters are described below.

Available filters with parameters

-median blur -ksize - kernel size (int)

-gaussian blur -ksize - Gaussian kernel size (int) -sigmaX - Kernel deviation in X direction (float) -sigmaY - Kernel deviation in Y direction (float)

-bilateral blur -d - ? (int) -sigmaColor - ? (int) -sigmaSpace - ? (int)

-denoise -h - ? (int) -tWS - template window size (int) -sWs - search window size (int)

-denoise_bilateral -sigmaColor - ? (int) -sigmaSpace - ? (int) -iterations - ? (int)

-denoise_tv_chambolle -weight - ? (float) -iterations - ? (int)

-sharpen -kernel - ? (numpy.matrix)

-unsharp mask -strength - ? (float) -ksize - kernel size (int)

-unsharp mask scikit -radius - ? (int) -amount - ? (float)

-morph -kernel - ? (numpy.matrix) -iterations - ? (int) -op - opencv MORPH operation (MORPH_OPEN, MORPH_CLOSE, MORPH_DILATE, MORPH_ERODE) -anchor - ? (tuple)

Comparison

Image before processing the fingerprint and after applying a presets.

Before	After

Generating curved finger model

It is possible to generate 3D printable stl model using --stl switch, which requires aditional parameter containing stl filename. In base mode the output model will be a curved finger model, with optional parameters following the filename controlling its shape. First optional parameter is papilar line height, second rate of curvature along x axis and the third is the rate of curvature along y axis.

• General form for curved stl generation

    python3 src/main.py input_file output_file dpi --config config_file preset --stl height_line height_base curvature_x curvature_y

• Working example curved stl generation

    python3 src/main.py res/examples/Palec_P4.tif res/examples/Palec_P4_from_preset.png 600 --config config/config.json git_example --stl 2 10 2 2

Generating planar finger model

Using -p switch makes the generated model planar. Optional parameters are model base thickness and papilar lines height, they are set after stl file name.

• General form for planar stl generation

    python3 src/main.py input_file output_file dpi --config config_file preset --stl height_line height_base -p

• Working example planar stl generation

    python3 src/main.py res/examples/Palec_P4.tif res/examples/Palec_P4_from_preset.png 600 --config config/config.json git_example --stl 2 10 -p

Mapping to existing finger model

This section will be added later, (if implemented) mapping of fingerprint to a given finger model.

Usage

usage: main.py [-h] [-m | --mirror | --no-mirror] [-p] input_file output_file dpi ([-c | --config config_file preset] | [filters ...]) [-s | --stl height_line height_base | --stl_file height_line curv_rate_x curv_rate_y]

Program for processing a 2D image into 3D fingerprint.

positional arguments: input_file input file path output_file output file path dpi dpi of used scanner filters list of filter names and their parameters in form [filter_name1 param1=value param2=value filter_name2 param1=value...]

options: -h, --help show this help message and exit -m, --mirror, --no-mirror switch to mirror input image -s [STL_FILE ...], --stl_file [STL_FILE ...] create stl model from processed image -p, --planar, --no-planar make stl shape planar instead of curved one -c CONFIG CONFIG, --config CONFIG CONFIG pair: name of the config file with presets, name of the preset

Roadmap

• Load and store image
• Apply basic image processing filters
  • Scale the image using given dpi
• Create filter library with more filters
  • Add more suitable filters to the library
• Use presets from config files
  • Add the option to save current filter preset to config file
• Add the option to modify filter parameters
• Convert the processed image to stl lithophane
• Add the option to curve the lithophane into the shape of a finger
• Add the option to map the fingerprint onto a given finger model
• Export final model ready for 3D print

Author

Rostislav Lán - xlanro00@stud.fit.vutbr.cz

Supervisor

Ing. Petr Malaník

Links

Project Link: https://strade.fit.vutbr.cz/git/xlanro00/BP_DP-xlanro00