Sfrax 1.0

Surfract is pleased to announce that Sfrax, an extensible Fractal Analysis platform is now available. Sfrax provides substantial improvements over the previous release (Kfrax). To register for a trial of sfrax please see our licensing page at:


New features include built in statistical differentiation and correlation as well as support for many more different analyses including:

  • Area-scale, Length-scale Fractal Analyses
  • Peak-to-Peak and Filling (2D / 3D) Analyses
  • Length Scale Anisotropy, Digs and Scratches (Experimental)

In addition Sfrax provides an extensible interface that allows for additional analyses to be made available from both Surfract and third-parties.

To pre-order Sfrax please see our Purchasing page.


Sfrax provides a integrated environment for analyzing, visualizing, differentiating and correlating many surfaces. It allows the user to load all of their surface measurements into one workspace and then compare and contrast different analyses.


Surface Analysis

Sfrax includes several standardized analysis methods including:

  • Length-scale
  • Area-scale

In addition it provides several types of analyses that have been developed but not yet standardized:

  • Filling (2D and 3D)
  • Peak-to-Peak

Finally it includes several experimental plugins including:

  • Length-scale Anisotropy
  • Radius-scale
  • Digs and Scratches
  • Length-scale Lengths

For more information about these analysis methods, references, or any other questions please contact us at


Sfrax includes support for a statistical F-Test differentiation, which provides a measure of how differentiable two groups of surfaces are based on a particular analysis.

This is useful especially in quantifying to some confidence whether two groups of surfaces can be differentiated using Area-scale, Length-scale or any of our other algorithms.


Finally Sfrax includes support for correlation between analysis and surface properties. This can be used to correlate, for instance, relative area (Area-scale analysis) and adhesive strength, or relative length (Length-scale) and resistance.

Surface Loading Support

We currently support a variety of formats including (*.sdf, *.sur (Mountains), *.scn (WPI SLM), *.opd (WYKO), *.plu, *.stp). We also support a number of ascii formats including some VRML, csv and asc files. Finally we support loading TIFF and BMP files.

If you have a question regarding a specific format please feel free to email us at


Sfrax includes advanced plotting features in addition to data export. Plots and Data can be easily incorporated from Sfrax into Word / Powerpoint / Excel.

Plots in Sfrax support showing multiple data series that may be grouped in order to highlight differences and similarities. In addition it provides robust configuration in order to change the styles of axes, plot labels, symbols as well as the legend.

Sfrax also provides export of data to csv files that can be easily loaded into programs such as Excel and Matlab for further analysis.


In addition to it's built in plotting features, Sfrax supports both 2D and 3D surface visualization. In addition it provides support for viewing the tiles used in Area-scale, Length-scale and Peak-to-Peak analysis.

These visualization tools help users to understand exactly how these analyses work and can also be used as explanatory figures in presentations or papers.


Sfrax features an extensible architecture which allows for custom analyses, correlations, surface modifications, and visualizations. In fact several plug-ins developed in collaboration with the WPI Surface Metrology Lab and the NSF are included with the Sfrax installer as an optional component.

For more information on the extensibility, or if you are interested in writing your own analyses using Sfrax tools, please feel free to contact us at

System Requirements

We currently support Sfrax running on the following Operating Systems:

  • Windows Vista (32 / 64 bit)
  • Windows XP (32 bit)
  • Windows 2000

In addition you will need a system with the following specifications in order to run Sfrax

  • Processor: Pentium 4, Athlon XP or newer. (Athlon 64 X2, Intel Core 2 Duo or better recommended)
  • Memory: 512mb (1gb or more recommended)
  • Hard disk space: 20mb for the program (additional space (> 1gb) required for caching data)
  • Graphics Card: Any card supporting 3D acceleration for 3D surface visualization (GeForce 3 / Radeon 8000 or newer reccomended)
  • Internet: Connection required for download and activation only.

If you have any specific questions as to whether your system can run Sfrax feel free to contact us at