To further a previous posting, our most recent paper entitled "On the Detection of Tracks in Spectrogram Images" has been accepted in the journal Pattern Recognition (http://www.sciencedirect.com/science/article/pii/S0031320312004712). A pre-review version of this paper is available online at http://hal.archives-ouvertes.fr/docs/00/64/49/37/PDF/LampertXX.pdf. Furthermore, please let me bring to your attention our previous publications on the topic: T. Lampert and S. O'Keefe, `A Detailed Investigation into Low-Level Feature Detection in Spectrogram Images', Pattern Recognition 44 (9): 2076–2092, 2011. https://sites.google.com/site/tomalampert/publications/Lampert11LowLevelInve... T. Lampert and S. O'Keefe, `A Survey of Spectrogram Track Detection Algorithms', Applied Acoustics 71 (2): 87–100, 2010. https://sites.google.com/site/tomalampert/publications/Lampert10Survey.pdf Please feel free to contact me if you have any questions regarding this research. Kind regards, Tom Lampert ----------------------- Dr. Thomas LampertResearch AssociateLSiiT, University of Strasbourg.Website: https://sites.google.com/site/tomalampert/publications