<?xml version='1.0' encoding='ISO-8859-1' standalone='yes' ?>
	<help>
		<element name="DESCRIPTION" text="This algorithm calculates the Perpendicular Vegetation Index (PVI) based on Perry and Lautenschlager, 1984. &#10;&#10;To calculate this index, a soil line is needed. A soil line is produces through linear regression of the near-infrared band and the red band for a sample of bare soil pixels. &#10;&#10;The index is the result of the following formula (a and b are the slope and intercept of the soil line, respectively):" description="Description" type="0">
			<image description="" file="pvi_perry_formula.jpg">
			</image>
		</element>
		<element name="ADDITIONAL_INFO" text="* Perry, C. J. &amp; Lautenschlager, L. F. Functional Equivalence of Spectral Vegetation Indices Remote Sensing and the Environment, 1984, 14, 169-182" description="Additional information" type="0">
		</element>
		<element name="EXTENSION_AUTHOR" text="Victor Olaya" description="Extension created by" type="0">
		</element>
		<element name="HELP_AUTHOR" text="Victor Olaya" description="Help file created by" type="0">
		</element>
		<element name="USER_NOTES" text="" description="User_notes" type="0">
		</element>
		<element name="LAYERRED" text="Layer with values corresponding to the spectral reflectance in the red region" description="Red layer" type="3">
		</element>
		<element name="BANDRED" text="Band with values corresponding to the spectral reflectance in the red region" description="Red band" type="3">
		</element>
		<element name="LAYERNIR" text="Layer with values corresponding to the spectral reflectance in the near infrared region" description="Near infrarred layer" type="3">
		</element>
		<element name="BANDNIR" text="Band with values corresponding to the spectral reflectance in the near infrared region" description="Near infrarred layer" type="3">
		</element>
		<element name="SLOPE" text="Slope of the soil line" description="Soil line slope" type="3">
		</element>
		<element name="INTERCEPT" text="Intercept of the soil line" description="Soil line intercept" type="3">
		</element>
		<element name="OUTPUT_DESCRIPTION" text="" description="Description" type="2">
		</element>
		<element name="RESULT" text="PVI" description="Result" type="2">
		</element>
	</help>
<?xml version='1.0' encoding='ISO-8859-1' standalone='yes' ?>