The Freehand Formula Entry System

Welcome to the FFES download page. The Freehand Formula Entry System (FFES) is a pen-based equation editor implemented in C++ and Tcl/Tk. FFES was created by Steve Smithies in 1999, when he was a Master's student at the University of Otago (NZ) under the supervision of Kevin Novins. Since that time, a number of others have contributed to FFES (see below). While best suited to use with a tablet, FFES can also be used with a mouse. FFES recognizes input using a character recognizer (CIT) and an expression parser (DRACULAE). Symbol recognition results are shown to the user by symbols drawn behind the user's strokes. Expression recognition results are shown using an image in the bottom panel of FFES and through the "Align" operation, which morphs symbols to ideal sizes and positions based on the recognized expression structure. Recognition results may be copied and pasted from FFES to other applications. FFES comes with documentation, and a number of related research publications are available from this page.

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Release Notes

The new release (version 0.3.1, May 2004) provides a number of bug fixes and improvements, particularly for the symbol correction facility, which is now simply a pop-up menu. CIT has been updated for compatability with modern C++ compilers (thanks goes here to David Mancel, who provided a patch for this). Also, for the Linux version DRACULAE is now compiled rather than interpreted, and image generation is now performed using dvi2bitmap, making the system significantly faster.

Currently the system runs fastest under Linux, where the 'dvi2bitmap' LaTeX .dvi rendering program is used. The Windows/Cygwin version uses a slower conversion via 'dvips' and the Img library that comes with the ActiveTcl distribution of Tcl/Tk. LaTeX image rendering is not yet working in the MacOSX version (see the screenshot above), and I have not had an opportunity to build the MacOSX version myself.

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Download and Installation Instructions

FFES, CIT, and DRACULAE are being distributed under the GNU Public License. The newest version of FFES is currently available for Linux and Windows (through Cygwin). An older MacOSX version was ported by Eric Bailey of Acuitus (Palo Alto, CA) in 2002.

Linux (version 0.3.1, May 2004)

1. First, download, build, and install dvi2bitmap. NOTE: Make sure that .gif image support had been compiled in using the -V option ("dvi2bitamp -V").
2. Then download and install TXL. Note: make sure you login as the root user, or that USERNAME=root when installing TXL.
3. Now download FFES 0.3.1 (for Linux) (as a gzipped tar archive)
4. Uncompress and untar the archive, and then follow the instructions in the ffes_0.3.1/INSTALL file.

Windows/Cygwin (version 0.3.1, May 2004)

1. If you have not already, install Cygwin; make sure that you install the LaTeX packages. NOTE: Make sure that the default text file format is set to "Unix."
2. Install ActiveTcl.
3. Install TXL for Windows. NOTE: Make sure to run the TXL install script (Install.bat) from within a Cygwin shell, and that you or the person installing TXL has 'administrator' priveleges.
4. Now download FFES 0.3.1 (for Cygwin) (as a gzipped tar archive)
5. Uncompress and untar the archive, and then follow the instructions in the ffes_0.3.1/INSTALL file.

MacOSX (version 0.2)

1. Download FFES for MacOSX.
2. Uncompress and untar the archive, and then follow the instructions in the MacOSX_FFES/INSTALL file.

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Contributors:

• FFES: Steve Smithies, Kevin Novins, Richard Zanibbi, Arlis Rose, David Tausky, Nick Willan
• CIT: James Arvo, Xavier Fan, Vladimir Fedorov, Yuanshan Guo, Kevin Novins, Steve Smithies, David Mancel, Richard Zanibbi
• DRACULAE: Richard Zanibbi, Eric Bailey (MacOSX port)

We also wish to acknowledge the contributions to FFES and DRACULAE provided by Dorothea Blostein and James R. Cordy. Gennaro Costagliola and Edward Lank also provided invaluable discussions in the early stages of designing DRACULAE.

FFES and DRACULAE are currently maintained at Queen's University, Canada, by Richard Zanibbi.

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Research Publications

Refereed Publications

About FFES and CIT:

• Steve Smithies. Freehand Formula Entry System. Master's thesis, University of Otago, Dunedin, New Zealand, May 1999.
• S. Smithies, K. Novins, J. Arvo. A Handwriting-Based Equation Editor, In Proc. Graphics Interface, Kingston, Ontario, Canada, June 1999.
• S. Smithies, K. Novins, and J. Arvo. Equation Entry and Editing via Handwriting and Gesture Recognition. Behaviour and Information Technology, 20(1):53-67, 2001. (title links to Kevin Novins' paper archive)
• Richard Zanibbi, Kevin Novins, James Arvo and Katherine Zanibbi. Aiding Manipulation of Handwritten Mathematical Expressions through Style-Preserving Morphs, In Proceedings of Graphics Interface 2001, Ottawa, Canada, June 2001, pp. 127-134.

  About DRACULAE:

• Richard Zanibbi, Dorothea Blostein and James R. Cordy. Baseline Structure Analysis of Handwritten Mathematics Notation, In Proceedings of the Sixth International Conference on Document Analysis and Recognition, Seattle, Washington, pp. 768-773, 2001.
• R. Zanibbi, D. Blostein, and J.R. Cordy. Recognizing Mathematical Expressions Using Tree Transformation. IEEE Transactions on Pattern Analysis and Machine Intelligence, Vol. 24, No. 11, pp. 1455-1467, November 2002.

Non-Refereed Publications

About DRACULAE:

• Richard Zanibbi. Recognition of Mathematics Notation via Computer Using Baseline Structure, Queen's University Technical Report ISSN-0836-0227-2000-439, 87 pages. (title links to Queen's Computing Science Technical Report archive).
• Richard Zanibbi, Dorothea Blostein and James R. Cordy. Directions in Recognizing Tabular Structures of Handwritten Mathematics Notation, In Proceedings of the Fourth International IAPR Workshop on Graphics Recognition, Kingston, Canada, pp. 493-499, September 2001.

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Contact Information

FFES is maintained by Richard Zanibbi, who is now at CENPARMI (Concordia Univeristy).

• email: zanibbi@cenparmi.concordia.ca

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Support:

This research has been supported by the Natural Sciences and Engineering Research Council of Canada, and the National Science Foundation (USA). Also, Virtual Ink donated a mimio for our research in 2000.