Changes between Version 80 and Version 81 of WKTRasterTutorial01


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Timestamp:
Jun 29, 2010, 2:11:28 PM (14 years ago)
Author:
pracine
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  • WKTRasterTutorial01

    v80 v81  
    162162As you can see, unlike most raster coverage loaded into a GIS, the area covered by this single table raster coverage is not strictly rectangular and the two big missing square areas are not filled with nodata values. Here you have only one table for the whole coverage which is build from many raster files loaded in a single step. You don't need 13 tables to store 13 rasters. We did this with one band SRTM files in TIF format, but it could have been 3 bands BMP files or JPEG and the number of files and the total size of the coverage does not really matter (PostgreSQL has a limit of 32 terabytes)...
    163163
    164 If you want to go to the pixel level and verify the integrity of the values associated to a sample of the raster,  you can (thanks to Jorge Arevalo and GDAL) view a vectorization of some tiles in OpenJUMP. Just type the following SQL query in the same query dialog:
     164[[Image(WKTRasterViewOfVectorizedTile.gif, align=right, 50%)]]
     165If you want to go to the pixel level and verify the integrity of the values associated to a sample of the raster,  you can (thanks to Jorge Arevalo and GDAL) view a vectorization of some tiles in OpenJUMP as in the right side image. Just type the following SQL query in the same query dialog:
    165166
    166167{{{