Changes between Version 24 and Version 25 of WKTRaster/Documentation01

Timestamp:

Dec 9, 2009, 12:09:54 PM (14 years ago)

Author:

pracine

Comment:

—

WKTRaster/Documentation01

@@ -195 +195 @@
 Like the PostGIS "geometry" type, the PostGIS WKT "raster" type is a new PostgreSQL type. This means each raster or raster tile is stored as a row of data in a PostgreSQL database table. It is a complex type, embedding information about the raster itself (width, height, number of bands, pixeltype for each band and nodata value for each band) along with its geolocalisation (pixelsize, upper left pixel center, rotation and SRID).
 
-=== '''PostGIS WKT Raster Rationale''' ===
+=== '''3.1.1 - PostGIS WKT Raster Rationale''' ===
 
 WKT Raster was designed with many objectives, to accommodate a myriad of dataset structures and a diversity of applications:
 
+'''Objective 1: Simplicity, Complementarity and Functionality -''' PostGIS WKT Raster provides a "raster" type that complements the existing PostGIS vectorial "geometry" type.  This new extension offers operators and functions that are similar to those available with the existing geometry type. They work in the same user-friendly manner, but are associated with a matricial geospatial data structure to support the use of rasters. PostGIS WKT Raster also includes a simple loader to import many raster formats into the database.
+
+'''Objective 2: Seamless Integration with the PostGIS geometry type -''' PostGIS WKT Raster enables PostGIS operators and functions to work seamlessly on both raster and geometry types, so that users:
+
+ * may use their prior knowledge of PostGIS in general, and of its geometry type operators and functions, when building SQL queries;
+ * expect similar behaviors when using these operators and functions with the raster type without having to consider whether their data are in vectorial or matricial form; 
+ * expect existing applications to work with new data loaded as rasters without (many) changes (to a certain conceptual limit).