Hello Moritz, > Hello, > > Some of my colleagues use eCognition for remote sensing data > classification. After having done so for teaching, we are now looking > into the possibilities of replacing proprietary with open source > solutions in research. > > eCognition uses an object-based approach to classification as opposed to > pixel-based. As they put it in their brochure: > > "The technology examines pixels not in isolation, but in context. It > builds up a picture iteratively, recognizing groups of pixels as objects. > Just like the human mind, it uses the color, shape, texture and size of > objects, as well as their context and relationships to draw the same > conclusions and inferences that an experienced analyst would draw."
The issue about how to emulate the eCog-approach into GRASS has been around for a while. Here are my two eurocents of knowledge: eCog consists of several algorithms. First, a segmenting tool (patented...) is used to divide a multispectral image stack into segments. Then, a knowledge-based (fuzzy) merging process gets you to the object-representation. So to do it with GRASS, we need to have a multispectral segmenting tool plus "the object stuff". I am not sure if there are any FOSS-segmenting tools in the works that do their job without signature files [medical imaging tools, maybe?]. For the next step, the abstraction from spatial segments to objects, object-oriented grass-friendly environments such as R or CLIPS/CAPE could be used to create a prototype/demonstrator. However, the performance for large data-sets might be significantly below a c/c++ implementation. Peter > Is something like this possible in GRASS ? > Or are there any other open source solutions using this approach ? > > Moritz -- Dr. Peter Löwe <[EMAIL PROTECTED]> GMX FreeMail: 1 GB Postfach, 5 E-Mail-Adressen, 10 Free SMS. Alle Infos und kostenlose Anmeldung: http://www.gmx.net/de/go/freemail _______________________________________________ grass-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-user
