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reference_book:image_virtualization [2017/07/25 01:08]
admin [Limitations]
reference_book:image_virtualization [2017/12/13 16:54] (current)
hermann
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-====== Image Virtualization ====== 
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-Image virtualization,​ map virtualization,​ or even raster virtualization is the name given by Dinamica EGO 4 to the ability of manipulating images with different extents, resolutions or number of lines and columns. 
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-Previous versions of Dinamica required all maps used as inputs of a model to have the same number of lines and columns (and by consequence the same extents). Dinamica EGO 4 changed this behavior by enforcing the proper use of map projections (all maps used as part of a model must share the same projection) and registration coordinates. ​ 
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-===== Requirements ===== 
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-Map computations in Dinamica since version 4 uses image virtualization to extent and modify at runtime the image dimensions making sure that all images presented to any operator have the same number of lines and columns. This allows images used by any computation to have different dimensions while retaining the ability to run the calculation in parallel at high speed. 
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-Typically, the only requirement when using virtualization is that all images must share the same projection, although different models can use different projections. It is also possible to use maps with different projections as part of a same model, as long as images with different projections are not given as inputs to the same functors at the same time. 
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-To facilitate the re-projection of maps ensuring that the projections are the same, a convenient wrapper around the [[http://​gdal.org/​gdalwarp.html|gdal_warp]] and [[http://​gdal.org/​gdal_translate.html|gdal_translate]] called [[:​Transform Map]] is provided. This functor simply runs those GDAL utilities distributed with Dinamica EGO 4. 
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-All analysis concerning projections and what they represent are performing internally using [[http://​gdal.org/​|GDAL]]. However, the map virtualization itself is performing independently by Dinamica. 
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 ====== Image Virtualization ====== ====== Image Virtualization ======