title: README author: Jan-Michael Rye

Synopsis

Read PicoQuant PTU files. The code follows the same parsing logic as the Python demo provided by PicoQuant but is up to 40 times faster due to the use of vectorized operations using Numpy arrays.

Links

• Homepage
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Usage

Python API

The data in the file is parsed into the following objects which are set as attributes of the parser:

• headers - A dict mapping header fields to their values.
• markers - A Pandas DataFrame where each row is a record index with an index, a time tag and a marker.
• overflows - A Pandas DataFrame where each row is a record with a record index and an overflow values.
• photons.csv - A Pandas DataFrame where each row is a record with a record index, a channel, a time tag, a resolved time tag (using the global resolution value), and a dtime value.

from pyptu import PTUParser

# A path to a PTU file.
path = /tmp/example.ptu

# Instantiate the parser. If no encoding is specified, the parser will first
# attempt to load files using UTF-8 and then Windows-1252 encodings. Other
# encodings can be specified using the "encoding" argument.
parser = PTUParser(path)

# Example of passing the "encoding" argument to the initialization method.
# parser = PTUParser(path, encoding='utf-8')

# Load the data. The load method also accepts an "encoding" argument.
parser.load()

# Example of passing the "encoding" argument to the load method.
# parser.load(encoding='windows-1252')

# Once the file is loaded, the loaded data can be accessed via the following
# attributes.

# The PTU header data.
headers = parser.headers

# The Pandas DataFrame of photon data.
photons = parser.photons

# The Pandas DataFrame of marker data.
markers = parser.markers

# The Pandas DataFrame of overflow values.
overflows = parser.overflows

# The loaded data can also be saved to standard file formats with the "save"
# method. Call the method with the path to the desired output directory.
parser.save('output')

Command-Line

The package installs the pyptu command-line tool that can be used to convert the data in a PTU file to JSON and CSV files. It accepts the path to a PTU file and an output directory.

# Extract the PTU data to files in an output directory.
pyptu example.ptu output_directory

The output directory will contain the following files:

• header.json - A JSON file with the headers described above.
• markers.csv - A CSV file containing the markers DataFrame.
• overflows.csv - A CSV file containing the overflows DataFrame.
• photons.csv - A CSV containing the photons DataFrame.

Help Message

$ pyptu -h
usage: pyptu [-h] [--encoding ENCODING] path dir

Extract PTU data to standard files.

positional arguments:
  path                 A path to a PTU file.
  dir                  A path to an output directory.

options:
  -h, --help           show this help message and exit
  --encoding ENCODING  Specify the input filetype encoding. It must be an encoding type supported
                       by Python. If not given, the following encodings will be tried, in order:
                       utf-8, windows-1252.