I3S Classic

We would like to state that we have no commercial or scientific interests. All we want is to help the community to improve research and in this way help conservation of endangered species. We do this (in our spare time) simply because we enjoy it and want to contribute.

All work is done for free, but as owners of small enterprises, working on the tool also means no income whatsoever. Donations or grants for future development are most welcome.


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Introduction to I3S Classic

I3S Classic is the oldest application of the I3S family. Annotation of features is limited to the location of the center of the markings, usually spots. No information such as shape or size is used. From the spatial relationships between the centers, a formula is used to calculate a similarity measure (A computer-aided program for pattern-matching natural marks on the spotted raggedtooth shark Carcharias taurus (Rafinesque, 1810), Van Tienhoven, A.M., Den Hartog, J.E., Reijns, R.A., & Peddemors, V.M., Journal of Applied Ecology 44, 273–280 (2007)). Lower scores mean better matches. To be able to calculate this measure with accuracy, a sufficient number of spots is required, typically 12 – 30. If more there are more than 30 spots available for annotation use the biggest or most prominent first. Annotating more than about 30 spots, without other information to compare spots such as size, may cause loss of accuracy.

For many species with a stable identification area (i.e. not very susceptible to curving) and lots of spots, e.g. whale sharks and ragged tooth sharks, annotation of spot centers is sufficient for reliable recognition. Experiments on a large whale shark database with over 2600 photos from 857 individuals show that when using 3 reference images, in 95.7% of the cases, the matching individual is in the top 10 of best matches shown by I3S Classic.

However, if the number of spots is either low, or showing a large variation in size and shape, you will need a more elaborate annotation scheme than centers alone. In these cases you should consider using I3S Spot (Manta) or I3S Pattern.

I3S Classic v4.0 allows you to set some internal parameters. These parameters were hard coded in I3S v2.0. For explanation of these parameters you are referred to the Classic manual coming with the installation. You can also contact us directly via e-mail.

For more information have a look at our video tutorials on youtube.

New features
New features in version 4.0 are:

  • Improved user interface showing the results. Now it is possible to view the image from the result list. With AutoZoom you directly zoom in on the area of interest. Finally, you can tell I3S to show either file names or directories in the result list.
  • Accuracy of the algorithm improved on the test databases (whale sharks and ragged tooth sharks).
  • Speed of the recognition improves by a factor 3 because I3S now uses the parallel processing power of your computer.
  • The possibility to use and manage multiple databases.
  • Easy and user-friendly definition of your own meta data structures.
  • Various tools to evaluate the performance of
  • I3S on your database and to compare two databases.
  • I3S comes with the possibility of automatic updates.
  • Key parameters of the recognition algorithm can be tailored for your specific data set.
  • Various minor bug fixes and improvements.

I3S comes with a simple conversion tool for your current database.

Tom Jardine-McNamara has created an app for the Maldives Whaleshark Research Organisation has developed based on I3S Classic.