J. Mas

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In the last two decades, advances in computer technology, earth observation sensors and GIS science, led to the development of " Object-based Image Analysis (OBIA) " as an alternative to the traditional pixel-based image analysis method. It was recognized that traditional pixel-based image analysis is limited because of the following reasons: image pixels(More)
This paper investigates the contribution of Enhanced Vegetation Index (EVI) data to the improvement of object-based image analysis using multi-spectral Moderate Resolution Imaging Spectral-radiometer (MODIS) imagery. Object-based image analysis classifies objects instead of single pixels. The idea to classify objects stems from the fact that most often the(More)
A new method for the enhancement of smoothing filters has been developed. It is an iterative and non-stationary (INS) process by which averaging is limited only to pixels that are 'statistically consistent' with the central pixel of the filter window. Adjustment of filter performance is achieved by the iterative calculation of filtered data variance. INS(More)
  • Y Gao, N Kerle, J F Mas, A Navarrete, I Niemeyer
  • 2007
Image segmentation is a preliminary and critical step in segment-based image analysis. Its proper evaluation ensures that the best segmentation result is used in image classification. In this paper, image segmentations were carried out and the results were evaluated with an objective function that aims at maximizing homogeneity within segments and(More)
A new approach to simultaneous spatial resolution and attenuation correction in SPECT imaging is presented. Before these corrections, scatter is removed on the projections. This removal is performed by spectral constrained factor analysis. The innovation reported here is the use of the different impulse responses of the system, according to the(More)
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