Florian Albrecht

Object-based class modeling for cadastre-constrained delineation of geo-objects.

Remote sensing technology still faces challenges when it comes to monitoring tasks that must be able to stand up to validation from technical, scientific, and practical points of view, in other words, when entering into established, fully operational workflows. In this paper, we present an approach for delineating and monitoring aggregated spatial units relevant to regional planning tasks, which has been fully validated within a 3,654 km 2 area in the Stuttgart Region of southwestern Germany. This has been achieved by developing algorithms for semi-automated (geo-) object-based class modeling of biotope complexes, which are aggregated, functionally homogenous (but not necessarily spectrally homogeneous) units. High levels of complexity in the target classes and the need for integration of auxiliary geodata as a priori knowledge meant that different methods of information extraction were required to be combined in an operational workflow, and that new validation strategies were needed for quality assessment. A total of 31,698 biotope complexes were delineated for the entire Stuttgart Region, with an average size of 11.5 ha for each complex. Approximately 86 percent of the biotope complex boundaries were shown to have been correctly delineated.

Object validity for operational tasks in a policy context

(GE)OBIA (Geographic Object-Based Image Analysis) utilises intelligent tools and algorithms for automatically delineating and labelling geographical objects. OBIA aims at converting traditional and established photo-interpretation tasks into operational use. Moreover, it may help to support the realisation of novel tasks in addressing composite classes, modelling new geographical realities, or observing changes at the individual object level, etc. Ranging from object representations (real-world objects or bona fide objects), via complex composite classes (real-world modelled objects) to concept-related fiat objects, OBIA poses new challenges for evaluating object validity in an operational context. This paper reflects on the need for an object-based validation concept, illustrates policy-related application scenarios and discusses qualitative and quantitative pillars under thematic and geo-spatial aspects.

Spatial and thematic assessment of object-based forest stand delineation using an OFA-matrix

Validacion de la cartografia generada del terreno a partir de una nuevo sistema de validacion propuesto