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ST_ColorTable

更新时间:

获取raster对象的某一个波段的颜色表信息,返回颜色表的JSON格式。

语法

text ST_ColorTable(raster raster_obj, integer band);

参数

参数名称

描述

raster_obj

raster对象。

band

指定的波段序号,从0开始。

描述

颜色表的JSON格式:

  • 4分量:

    '{"compsCount":4,
        "entries":[
            {"value":0,"c1":0,"c2":0,"c3":0,"c4":255},
            {"value":1,"c1":0,"c2":0,"c3":85,"c4":255},
            {"value":2,"c1":0,"c2":0,"c3":170,"c4":255}
        ]
    }'
  • 3分量:

    '{"compsCount":3,
        "entries":[
            {"value":0,"c1":0,"c2":0,"c3":0},
            {"value":1,"c1":0,"c2":0,"c3":85},
            {"value":2,"c1":0,"c2":0,"c3":170}
        ]
    }'

如果不存在颜色表,函数返回空值。

示例

select ST_ColorTable(raster_obj,0) from raster_table where id = 1;

__________________________________
'{"compsCount":3,
    "entries":
    [
        {"value":0,"c1":0,"c2":0,"c3":0},
        {"value":1,"c1":0,"c2":0,"c3":85},
        {"value":2,"c1":0,"c2":0,"c3":170}
    ]
}'