<xs:attribute default="0" name="contrast" xmlns:xs="http://www.w3.org/2001/XMLSchema">
  <xs:annotation>
    <xs:documentation>Contrast adjustment for the layer. Positive values exaggerate color separation (as the value approaches 1, the result is either pure black (for colors below the grey threshold) or pure solid color (for colors above the threshold), for example, a dark red will become pitch black, whereas a bright red will become solid red). Negative values merge/dissolve the colors (as the value approaches -1, the result is all gray).</xs:documentation>
  </xs:annotation>
  <xs:simpleType>
    <xs:restriction base="xs:double">
      <xs:minInclusive value="-1" />
      <xs:maxInclusive value="1" />
    </xs:restriction>
  </xs:simpleType>
</xs:attribute>