PVI
サマリー
Calculates the Perpendicular Vegetation Index (PVI) from a multiband raster object and returns a raster object with the index values.
ディスカッション
The Perpendicular Vegetation Index (PVI) method is similar to a difference vegetation index; however, it is sensitive to atmospheric variations. When using this method to compare images, it should only be used on images that have been atmospherically corrected.
\(PVI \space = \space (NIR \space - \space a \space * \space Red \space - \space b) \space / \space (√(1 \space + \space a ^{2} ))\)
a—slope of the soil line
b—gradient of the soil line
This index outputs values between -1.0 and 1.0.
For information about other multiband raster indexes, see the Band Arithmetic raster function.
The referenced raster dataset for the raster object is temporary. To make it permanent, you can call the raster object's save method.
構文
PVI(raster, {nir_band_id}, {red_band_id}, {a}, {b})
| パラメーター | 説明 | データ タイプ |
|---|---|---|
|
raster |
The input raster. |
Raster |
|
nir_band_id |
The band ID of the near-infrared band. The ID index uses one-based indexing. The default value is 4. |
Integer |
|
red_band_id |
The band ID of the red band. The ID index uses one-based indexing. The default value is 3. |
Integer |
|
a |
The slope of the soil line. The default value is 0.3. |
Double |
|
b |
The gradient of the soil line. The default value is 0.5. |
Double |
戻り値
| データ タイプ | 説明 |
|---|---|
|
Raster |
The output raster object with the PVI index values. |
コードのサンプル
Calculates the Perpendicular Vegetation Index for a Landsat 8 image.
import arcpy
PVI_raster = arcpy.ia.PVI("Landsat8.tif", 5, 4, 0.3, 0.5)