ParticleDetection.utils.data_conversions

Collection of function to convert between different file formats used over the course of the particle detection project, e.g. camera calibrations from MATLAB to the now used json-format.

Authors: Adrian Niemann (adrian.niemann@ovgu.de)

Date: 02.11.2022

convert_txt_config(folder: Path)

Convert camera calibrations from MATLAB’s *.txt/*.mat to *.json format.

This function converts a stereo camera calibration saved by MATLAB to *.txt and *.mat files into the *.json format used by functions in this package.

The resulting files are saved as converted.json and world_transformations_converted.json.

Parameters

folder (Path) –

Folder containing the stereo calibration output, consisting of the following files:

c.txt, f.txt, c2.txt, f2.txt, kc.txt, kc2.txt, R.txt, transvek.txt, transformations.mat

csv_combine(input_files: List[str], output_file: str = 'rods_df.csv') → str

Concatenates multiple *.csv files to a single one.

The given input files are combined into a single one. The function does not distinguish what data it is given and might fail, if it is not rod position data in all given files. The function does NOT check for duplicates.

Parameters

• input_files (List[str]) – *.csv files that contains rod position data.

• output_file (str, optional) – Path to the output file. If this is just a file name without a path, the parent directory of the first input file is taken as the intended file location. By default "rods_df.csv".

Returns

str – Path to the written, combined file. The string is empty, if nothing has been written.

csv_extract_colors(input_file: str) → List[str]

Extract the rod position data into one file per color.

This functions saves a new file for each color that is present in the given data. The original file name is thereby extended by the name of the respective color, i.e. old_name_foundcolor.csv.

Parameters

input_file (str) – *.csv file that contains rod position data for multiple colors, i.e. has a column "color".

Returns

List[str] – Returns a list of paths to the files, that were written.

csv_split_by_frames(input_file: str, cut_frames: List[int]) → List[str]

Splits the rod data at the given frames.

Splits the given *.csv file into individual files at the given frame numbers.

Example:

The data has frames from 0 to 33.

cut_frames = [15, 20, 25]

-> out_0_14.csv, out_15_19.csv, out_20_24.csv, out_25_33.csv

Parameters

• input_file (str) – Path to a *.csv file containing rod position data.

• cut_frames (List[int]) – Frames at which to partition the data. All frames in the original data are perserved. The lower bound is inclusive, while the upper bound is exclusive.

Returns

List[str] – List of paths to the written files. This list is empty, if no files were written.

txt2mat(input_folder: Path, frames: Iterable[int], expected_rods: int, cam1_id: str = 'gp1', cam2_id: str = 'gp2', output_folder: Optional[Path] = None) → None

Read rod position data in old *.txt format and save it in *.mat format.

Converts the rod positions from the *.txt format to *.mat format assuming, that only one color is saved in the given input folder. The converted files are then saved to two subfolders of the output folder, named after cam1_id and cam2_id.

Parameters

• input_folder (Path) – Folder containing the 3D data in txt-files of format: {frame:05d}.txt

• frames (Iterable[int]) – Frame numbers found in the input folder and intended to be converted.

• expected_rods (int) – Number of rods to expect in one frame.

• cam1_id (str, optional) – First camera’s identifier in the given dataset. By default "gp1".

• cam2_id (str, optional) – Second camera’s identifier in the given dataset. By default "gp2".

• output_folder (Path, optional) – Parent folder of the two output folders. By default set to the parent folder of the input folder.