ST_PixelAsPolygon — 返回限定特定行和列的像素的多边形几何形状。
geometry ST_PixelAsPolygon(raster rast, integer columnx, integer rowy);
返回限定特定行和列的像素的多边形几何形状。
可用性: 2.0.0
This example returns a raster pixel polygon.
SELECT i, j, ST_PixelAsPolygon(foo.rast, i, j) As b1pgeom
FROM dummy_rast As foo
CROSS JOIN generate_series(1, 2) As i
CROSS JOIN generate_series(1, 1) As j
WHERE rid=2;
i | j | b1pgeom ---+---+----------------------------------------------------------------------------- 1 | 1 | POLYGON((3427927.75 5793244,3427927.8 5793244,3427927.8 5793243.95,... 2 | 1 | POLYGON((3427927.8 5793244,3427927.85 5793244,3427927.85 5793243.95, ..