This topic describes the ST_Polygonize function. This function vectorizes a grid object based on its pixel value.
Syntax
setof record ST_Polygonize( raster rast,
integer bandnumber,
out geom geometry,
out id integer,
out value float8);Parameters
Parameter | Required | Description |
rast | Yes | The input grid object. |
bandnumber | Yes | The number of the band. The value starts from 0. |
Examples
select ST_Polygonize(rast,1) from rast_table where id=1;Input
Output
