ST_PixelWidth
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## Name

ST_PixelWidth — Returns the pixel width in geometric units of the spatial reference system.

## Synopsis

`double precision ST_PixelWidth(`raster rast`)`;

## Description

Returns the width of a pixel in geometric units of the spatial reference system. In the common case where there is no skew, the pixel width is just the scale ratio between geometric coordinates and raster pixels.

The following diagram demonstrates the relationship:

Pixel Width: Pixel size in the i direction

Pixel Height: Pixel size in the j direction

## Examples: Rasters with no skew

    SELECT ST_Width(rast) As rastwidth, ST_PixelWidth(rast) As pixwidth,
        ST_ScaleX(rast) As scalex, ST_ScaleY(rast) As scaley, ST_SkewX(rast) As skewx,
        ST_SkewY(rast) As skewy
        FROM dummy_rast;

        rastwidth | pixwidth | scalex | scaley | skewx | skewy
        -----------+----------+--------+--------+-------+----------
        10 |        2 |      2 |      3 |     0 |        0
         5 |     0.05 |   0.05 |  -0.05 |     0 |        0

## Examples: Rasters with skew different than 0

    SELECT ST_Width(rast) As rastwidth, ST_PixelWidth(rast) As pixwidth,
        ST_ScaleX(rast) As scalex, ST_ScaleY(rast) As scaley, ST_SkewX(rast) As skewx,
        ST_SkewY(rast) As skewy
        FROM (SELECT ST_SetSkew(rast,0.5,0.5) As rast
        FROM dummy_rast) As skewed;

        rastwidth |     pixwidth      | scalex | scaley | skewx | skewy
        -----------+-------------------+--------+--------+-------+----------
        10 |  2.06155281280883 |      2 |      3 |   0.5 |      0.5
         5 | 0.502493781056044 |   0.05 |  -0.05 |   0.5 |      0.5

## See Also

ST_PixelHeight, ST_ScaleX, ST_ScaleY, ST_SkewX, ST_SkewY

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