Changes between Version 208 and Version 209 of WKTRaster/SpecificationWorking03

Timestamp:

Jul 24, 2012, 1:44:13 PM (12 years ago)

Author:

pracine

Comment:

—

WKTRaster/SpecificationWorking03

@@ -511 +511 @@
 
 ----
+== '''Objective FV.23 - Being able to set and get values for part of a raster.''' ==
+
+'''ST_SetValues'''
+
+ Set a set of pixel to a value.
+
+ Those functions are provided as a faster way to set pixels than the (future) two rasters version of ST_MapAlgebra which can also be used when more conditional flexibility is necessary. They should also be used in this version of ST_MapAlgebra to quicly set large areas to a single value.
+
+ '''Variants'''
+
+ The first series of variant set a defined area of the raster to a value.
+
+  1) ST_SetValues(rast raster, band int, x int, y int, width int, height int, val float8, keepdestnodata boolean)
+
+  2) ST_SetValues(rast raster, x int, y int, width int, height int, val float8, keepdestnodata boolean)
+
+  3) ST_SetValues(rast raster, x int, y int, width int, height int, val float8)
+
+  4) ST_SetValues(rast raster, band int, x int, y int, width int, height int, val float8)
+
+ The second series of variant set a defined area of the raster to corresponding values of another raster.
+
+  5) ST_SetValues(rast1 raster, band1 int, x int, y int, width int, height int, rast2 raster, band2 int, keepdestnodata boolean, keepsourcenodata boolean)
+
+  6) ST_SetValues(rast1 raster, x int, y int, width int, height int, rast2 raster, keepdestnodata boolean, keepsourcenodata boolean)
+
+  7) ST_SetValues(rast1 raster, x int, y int, width int, height int, rast2 raster)
+
+ x, y, width & height define the area of the raster to be edited. x & y are the raster coordinates of the upper left corner of this are. When x, y, width or height are out of the raster range, only the part of the range intersecting with the raster is set to the new value.
+
+ val is the new value to be set.
+
+ When keepdestnodata is TRUE, destination nodata value pixels are not set. Default is FALSE so that nodata value pixels are set.
+
+ When keepsourcenodata is TRUE, source nodata value pixels are not copied. Default is FALSE so that nodata value pixels are copied.
+
+ Variant 2 assume band to be 1.
+
+ Variant 3 assume band to be 1 and keepdestnodata to be FALSE.
+
+ Variant 4 assume only keepdestnodata to be FALSE.
+
+ Variant 6 assume both bands to be 1.
+
+ Variant 7 assume both bands to be 1, keepdestnodata to be FALSE and keepsourcenodata to be FALSE.
+
+ '''Implementation details'''
+ 
+ PL/pgSQL prototypes can be found in http://trac.osgeo.org/postgis/browser/trunk/raster/scripts/plpgsql/st_setvalues.sql
+
+----
 == '''Other functions''' ==