ST_Mean4ma
Name
ST_Mean4ma — Raster processing function that calculates the mean pixel value in a neighborhood.
Synopsis
float8
ST_Mean4ma
(
float8[][]
matrix
, text
nodatamode
, text[]
VARIADIC args
)
;
double precision
ST_Mean4ma
(
double precision[][][]
value
, integer[][]
pos
, text[]
VARIADIC userargs
)
;
Description
Calculate the mean pixel value in a neighborhood of pixels.
For Variant 2, a substitution value for NODATA pixels can be specified by passing that value to userargs.
Variant 1 is a specialized callback function for use as a callback parameter to ST_MapAlgebraFctNgb . |
Variant 2 is a specialized callback function for use as a callback parameter to ST_MapAlgebra (callback function version) . |
Use of Variant 1 is discouraged since ST_MapAlgebraFctNgb has been deprecated as of 2.1.0. |
Availability: 2.0.0
Enhanced: 2.1.0 Addition of Variant 2
Examples: Variant 1
SELECT rid, st_value( st_mapalgebrafctngb(rast, 1, '32BF', 1, 1, 'st_mean4ma(float[][],text,text[])'::regprocedure, 'ignore', NULL), 2, 2 ) FROM dummy_rast WHERE rid = 2; rid | st_value -----+------------------ 2 | 253.222229003906 (1 row)