In this paper Hong Yu from the University of Wisconsin in Milwaukee describes a system for better automated characterization of figures from scientific papers. The system is available through their webserver "Ask Hermes".
If you want to learn more about the system I suggest you read the paper. Or watch their video.
Basically the general idea is summarized in their background section of the abstract:
Figures are important experimental results that are typically reported in full-text bioscience articles. Bioscience researchers need to access figures to validate research facts and to formulate or to test novel research hypotheses. On the other hand, the sheer volume of bioscience literature has made it difficult to access figures. Therefore, we are developing an intelligent figure search engine (http://figuresearch.askhermes.org). Existing research in figure search treats each figure equally, but we introduce a novel concept of “figure ranking”: figures appearing in a full-text biomedical article can be ranked by their contribution to the knowledge discovery.I particularly like that they also allow searching just for open access figures, which may be of significant value to people who want to do things like make a slide presentation with no copyrighted/protected material in it. For example see the results of a search for open access figures using the keyword phylogenomics.
Anyway - definitely worth checking this out.
Yu, H., Liu, F., & Ramesh, B. (2010). Automatic Figure Ranking and User Interfacing for Intelligent Figure Search PLoS ONE, 5 (10) DOI: 10.1371/journal.pone.0012983