A String Matching Computer-Assisted System for Dolphin Photoidentification
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This paper presents a syntactic/semantic string representation scheme as well as a string matching method as part of a computer-assisted system to identify dolphins from photographs of their dorsal fins. A low-level string representation is constructed from the curvature function of a dolphin's fin trailing edge, consisting of positive and negative curvature primitives. A high-level string representation is then built over the low-level string via merging appropriate groupings of primitives in order to have a less sensitive representation to curvature fluctuations or noise. A family of syntactic/semantic distance measures between two strings is introduced. A composite distance measure is then defined and used as a dissimilarity measure for database search, highlighting both the syntax (structure or sequence) and semantic (attribute or feature) differences. The syntax consists of an ordered sequence of significant protrusions and intrusions on the edge, while the semantics consist of seven attributes extracted from the edge and its curvature function. The matching results are reported for a database of 624 images corresponding to 164 individual dolphins. The identification results indicate that the developed string matching method performs better than the previous matching methods including dorsal ratio, curvature, and curve matching. The developed computer-assisted system can help marine mammalogists in their identification of dolphins, since it allows them to examine only a handful of candidate images instead of the currently used manual searching of the entire database. © 2000 Biomedical Engineering Society.
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- A String Matching Computer-Assisted System for Dolphin Photoidentification
Annals of Biomedical Engineering
Volume 28, Issue 10 , pp 1269-1279
- Cover Date
- Print ISSN
- Online ISSN
- Kluwer Academic Publishers-Plenum Publishers
- Additional Links
- Dolphin photographic identification
- Computer-assisted system
- Dorsal fin curvature representation
- Syntactic/semantic curve modeling
- String matching
- Dolphin image database
- Industry Sectors
- Author Affiliations
- 1. Electrical Engineering Department, Texas A & M University, College Station, TX
- 2. University of Texas Medical Branch, Galveston, TX
- 3. Marine Mammal Research Program, Texas A & M University at Galveston, Galveston, TX