How do you calculate NDVI and NDWI?

Posted on by Drake Andrew

How do you calculate NDVI and NDWI?

So, following formula gives Normalized Difference Vegetation Index (NDVI).

  1. NDVI = (NIR – Red) / (NIR + Red)
  2. BU = NDBI – NDVI.
  3. NDBI = (SWIR – NIR) / (SWIR + NIR)
  4. NDWI = (NIR – SWIR) / (NIR + SWIR)
  5. MNDWI = (Green – SWIR) / (Green + SWIR)

How do I read a NDVI map?

The most common measurement is called the Normalized Difference Vegetation Index (NDVI). Very low values of NDVI (0.1 and below) correspond to barren areas of rock, sand, or snow. Moderate values represent shrub and grassland (0.2 to 0.3), while high values indicate temperate and tropical rainforests (0.6 to 0.8).

How do you make a NDVI map?

Now, let’s go through the steps for how to create an NDVI map.

  1. Enable Image Analysis Toolbar. First, enable the Image Analysis Toolbar (Windows > Image Analysis).
  2. Check Scientific Output Properties. Second, under image analysis options, select the red band and the near-infrared band.
  3. Click the NDVI Icon.
  4. Export Raster.

How does NDVI calculate using Modis data?

In MODIS, Red and NIR are represented by band 1 and 2. This is the underlying concept of calculating NDVI….NDVI = (NIR — Red) / (NIR + Red)

  1. Import the image collection of NDVI from MODIS data catalog.
  2. Filter the date and the area of interest.
  3. Colorized or visualize the NDVI image.
  4. Display the NDVI.

How do you calculate NDVI?

Normalized Difference Vegetation Index (NDVI) describes the vegetation density and assessing changes in plant health. NDVI is calculated as a ratio between the red (R) and near-infrared (NIR). In this tutorial learn how to apply the NDVI formula and calculate vegetation patterns. In Landsat 4-7, NDVI = (Band 4 – Band 3) / (Band 4 + Band 3).

How do I create an NDVI image in ERDAS IMAGINE?

Your objective today is to create an NDVI image using the Indices dialog within ERDAS IMAGINE. In this video you’ll see how to find and open the Indices dialog, check and set your NDVI preferences, look at and preview the image, and finally, generate an output NDVI image. If playback doesn’t begin shortly, try restarting your device.

How to create an NDVI file for IRS Liss-III?

IRS Liss-III, NDVI = (Band 3 – Band 2) / (Band 3 + Band 2). NDVI always ranges from -1 to +1. 1.On the Raster tab, the Classification group expend Unsupervised and selects NDVI. 2. The Indices dialog is open, select Input file and Output file, and most important choose Sensor (ex. IRS Liss-III) for your Satellite image.

How to create an NDVI file for a satellite image?

IRS Liss-III, NDVI = (Band 3 – Band 2) / (Band 3 + Band 2). NDVI always ranges from -1 to +1. 1.On the Raster tab, the Classification group expend Unsupervised and selects NDVI. 2. The Indices dialog is open, select Input file and Output file, and most important choose Sensor (ex. IRS Liss-III) for your Satellite image. 3.