Development Status
- 4 - Beta
Intended Audience
- Science/Research
- Developers
Operating System
- OS Independent
Programming Language
- Python :: 3 :: Only
- Python :: 3.11
- Python :: 3.12
- Python :: 3.13
- Python :: 3.14
Netpbmfile is a Python library to read and write image files in the Netpbm or related formats:
PBM (Portable Bit Map): P1 (text) and P4 (binary)
PGM (Portable Gray Map): P2 (text) and P5 (binary)
PPM (Portable Pixel Map): P3 (text) and P6 (binary)
PNM (Portable Any Map): shorthand for PBM, PGM, and PPM collectively
PAM (Portable Arbitrary Map): P7, bilevel, gray, rgb, and arbitrary depths
PGX (Portable Graymap Signed): PG, signed grayscale
PFM (Portable Float Map): Pf (gray), PF (rgb), and PF4 (rgba), read-only
XV thumbnail: P7 332 (rgb332), read-only
The Netpbm formats are specified at https://netpbm.sourceforge.net/doc/.
The PGX format is specified in ITU-T Rec. T.803.
No gamma correction or scaling is performed.
- Author:
- License:
BSD-3-Clause
- Version:
2026.1.29
- DOI:
Quickstart
Install the netpbmfile package and all dependencies from the Python Package Index:
python -m pip install -U "netpbmfile[all]"
See Examples for using the programming interface.
Source code and support are available on GitHub.
Requirements
This revision was tested with the following requirements and dependencies (other versions may work):
Revisions
2026.1.29
Fix code review issues.
2026.1.8
Improve code quality.
2025.12.12
Drop support for Python 3.10, support Python 3.14.
2025.5.8
Remove doctest command line option.
2025.1.1
Improve type hints.
Drop support for Python 3.9, support Python 3.13.
2024.5.24
…
Refer to the CHANGES file for older revisions.
Examples
Write a numpy array to a Netpbm file in grayscale binary format:
>>> import numpy
>>> data = numpy.array([[0, 1], [65534, 65535]], dtype=numpy.uint16)
>>> imwrite('_tmp.pgm', data)
Read the image data from a Netpbm file as numpy array:
>>> image = imread('_tmp.pgm')
>>> numpy.testing.assert_equal(image, data)
Access meta and image data in a Netpbm file:
>>> with NetpbmFile('_tmp.pgm') as pgm:
... pgm.magicnumber
... pgm.axes
... pgm.shape
... pgm.dtype
... pgm.maxval
... pgm.asarray().tolist()
...
'P5'
'YX'
(2, 2)
dtype('>u2')
65535
[[0, 1], [65534, 65535]]
View the image and metadata in the Netpbm file from the command line:
$ python -m netpbmfile _tmp.pgm
