Gwyddion is a modular program for SPM (scanning probe microscopy) data visualization and analysis. Primarily it is intended for analysis of height fields obtained by scanning probe microscopy techniques (AFM, MFM, STM, SNOM/NSOM), however it can be generally used for any other height field and image analysis, for instance for analysis of profilometry data (learn more about Gwyddion features).

Gwyddion is Free and Open Source software, covered by GNU General Public License. It aims to provide multiplatform modular program for 2D data analysis that could be easily extended by modules and plug-ins. Moreover, the status of free software enables to provide source codes to developers and users, which makes the further program improvement easier.

Gwyddion works on GNU/Linux, Microsoft Windows, Mac OS X and FreeBSD operating systems on common architectures, all systems can be used also for developement. Its graphical user interface is based on Gtk+ and port to other systems supported by Gtk+ should be possible.

The current version Gwyddion provides at least the following visualization and processing functions (this list is updated occasionally):
1. visualization: false color representation with different types of mapping
2. shaded, logarithmical, gradient- and edge-detected, local contrast representation, Canny lines
3. OpenGL 3D data display: false color or material representation
4. easily editable color maps and OpenGL materials
5. basic operations: rotation, flipping, inversion, data arithmetic, crop, resampling
6. leveling: plane leveling, profiles leveling, three-point leveling, facet leveling, polynomial background removal, leveling along user-defined lines
7. value reading, distance and angle measurement
8. profiles: profile extraction, measuring distances in profile graph, profile export
9. filtering: mean, median, conservative denoise, Kuwahara, minimum, maximum, checker pattern removal
10. general convolution filter with user-defined kernel
11. statistical functions: Ra, RMS, projected and surface area, inclination, histograms, 1D and 2D correlation functions, PSDF, 1D and 2D angular distributions, Minkowski functionals, facet orientation analysis
12. statistical quantities calculated from area under arbitrary mask
13. row/column statistical quantities plots
14. ISO roughness parameter evaluation
15. grains: threshold marking and unmarking, watershed marking
16. grain statistics: overall and distributions of size, height, area, volume, boundary length, bounding dimensions
17. intergral transforms: 2D FFT, 2D continuous wavelet transform (CWT), 2D discrete wavelet transform (DWT), wavelet anisotropy detection
18. fractal dimension analysis
19. data correction: spot remove, outlier marking, scar marking, several line correction methods (median, modus)
20. removal of data under arbitrary mask using Laplace or fractal interpolation
21. automatic xy plane rotation correction
22. arbitrary polynomial deformation on xy plane
23. 1D and 2D FFT filtering
24. fast scan axis drift correction
25. mask editting: adding, removing or intersecting with rectangles and ellipses, inversion, extraction, expansion, shrinking
26. simple graph function fitting, critical dimension determination
27. force-distance curve fitting
28. axes scale callibration
29. merging and immersion of images
30. tip modelling, blind estimation, dilation and erosion

The license of this software is Free, you can free download and free use this graphing software.