MHM – Multiscale Heterogeneity Map
Thème : Image Textural Analyses (Analyse de texture d’images)
Licence : Logiciel libre (freeware)
Système d’exploitation : Windows, Macintosh, Linux…
MHM, for Multiscale Heterogeneity Map, is a convenient tool aiming at analysing almost every kind of surface patterns. It focuses on a multiscale analysis and offers multiscale maps and profiles of the mostly used pattern indices. This method is summarized within a coherent opensource software that makes analyses very friendly for ecological, remote sensing and even biological or physical studies. MHM is fully complementary to geostatistical tools (dedicated to point-pattern analyses) or to Fragstats modules (generally offering monoscale analyses) and focuses on patchy mosaics. MHM software has been developed from Gaucherel’s Matlab® routines (see references) and has been recently transformed into an open Java® multiplatform software (see developer forum). MHM works with images saved in raster mode and deliverates quantified indices in similar and different formats.
Spatial heterogeneity, in the wide sense of pattern complexity and variability, appears to be one of the dominant causes of ecological functions and processes. The most widely used quantification of heterogeneity in environmental studies is based on derived Shannon information theory indices. Yet, such heterogeneity index is not able to quantify the surface patterns of a landscape with a fully explicit scheme (understand, at each place and scale of the landscape). MHM tool proposes to draw multiscale, averaged, heterogeneity maps to bypass this disadvantage and to capture the scaling behavior of the landscape. MHM combines mostly used pattern indices with the moving window principle. This multiscale map is associated to a heterogeneity profile averaging at each scale the spatial information over the whole landscape. Confidence levels have been estimated on the basis of a simple neutral landscape model to detect significant heterogeneity fluctuations. Edge effects are managed with various algorithms. This methodology is illustrated further on both categorical (patchy) and numerical (point-data) real mosaics: a and a in north Atlantic. Heterogeneity analyses of both image types can simultaneously reveal subtle quantitative and qualitative features (gradients, boundaries, random or patchy patterns at successive scales) that would need otherwise combinations of many specific methods. A more powerfull MHM (research) version, available upon request, is under progress.
MHM is an Open Java multiplatform software developed as a project during degree studies at Montpellier University by Frederic Escandell, Cedric Le Brouster and Pierre Sicot with Cedric Gaucherel as a supervisor. This work supposed to first understand Matlab’s routines, then to build an object oriented conception for the same purpose in order to meet various requirements such as:
- to keep a reusable conception and use for instance Model View Controller pattern;
- to have a complete, ergonomic and intuitive user interface;
- to fully rewrite the Matlab’s code, which was thought within an object-oriented scheme;
- to finally have powerful and rapid algorithms.
The work has been divided as follows:
- Frederic Escandell: Management; UML Conception (design pattern MVC); Controller and Model layer; Double Core optimization (Multi Threading); Use of Java Advanced Imaging and JFreeChart API.
- Cedric Le Brouster: Realization and optimization of the computation algorithms for the various image analyses. Understanding and translating Matlab’s routines and comparison with the new Java ones.
- Pierre Sicot : Ergonomic user interface; Wrapping the application for Linux, Mac OS, Windows.
Here, you may find MHM files.
- Source Code: MHM_Sources.zip
- Windows Package: Setup_MHM.zip
- MacIntosh and Linux Packages: MHM_jar.zip
(Please, notice that working images have to be carrefully prepared according to the « help » section of the software. In particular, the file format, the background code (-9999), the size of the image and the spatial resolution should carrefully fit the question addressed). Any enquiry about the software should to be sent to C. Gaucherel.
Short MHM bibliography
- Gaucherel, C., Multiscale heterogeneity map and associated scaling profile for landscape analysis. Landscape and Urban Planning, 82 (3): 95-102, Sep 2007.
- Gaucherel, C., F. Burel, and J. Baudry, Multiscale and Surface pattern analysis of the effect of landscape organisation on carabid beetles distribution. Ecological Indicators, 7 (3): 598-609, Jul 2007.
- Gaucherel, C., Self-similar land cover heterogeneity of temperate and tropical landscapes. Ecological Complexity, accepted, 2008.
For any questions or remarks, please contact : Cédric Gaucherel
See also the didactical and user-friendly site about MHM: http://cmp.gj05.fr/accuei_mhm_fr.html