how to calculate NDVI using ArcGis
Ғылым және технология
The Normalized Difference Vegetation Index (NDVI) is a standardized index allowing you to generate an image displaying greenness (relative biomass). This index takes advantage of the contrast of the characteristics of two bands from a multispectral raster dataset-the chlorophyll pigment absorptions in the red band and the high reflectivity of plant materials in the near-infrared (NIR) band.
An NDVI is often used worldwide to monitor drought, monitor and predict agricultural production, assist in predicting hazardous fire zones, and map desert encroachment. The NDVI is preferred for global vegetation monitoring because it helps compensate for changing illumination conditions, surface slope, aspect, and other extraneous factors (Lillesand 2004).
The differential reflection in the red and infrared (IR) bands enables you to monitor density and intensity of green vegetation growth using the spectral reflectivity of solar radiation. Green leaves commonly show better reflection in the near-infrared wavelength range than in visible wavelength ranges. When leaves are water stressed, diseased, or dead, they become more yellow and reflect significantly less in the near-infrared range. Clouds, water, and snow show better reflection in the visible range than in the near-infrared range, while the difference is almost zero for rock and bare soil. The NDVI process creates a single-band dataset that mainly represents greenery. The negative values represent clouds, water, and snow, and values near zero represent rock and bare soil.
Пікірлер: 15
Thankyou so much for the tutorial.
Where i can get the landsat tif with 6 spectral channels? When i download them on usgs they only have 3 channels.
very important, thanks
Thanks for your important show about NDVI. Please you had been figure out that NDVI=(PIR-R)/(PIR+R) where PIR is the near infra red band and R is the red band, as known the near infra red band is the band number (B5) where the red band is the band number (B4). With best wishes for you.
@made4geek
6 жыл бұрын
thaks sir, PIR= proche infra rouge (francais). I agree, it's true.
@ali.k2945
4 жыл бұрын
yes true
thank you
Hey!! i couldn't get my values ranging between 1 to -1. Can you please help!?
Thanku for the helpfull and interesting video. I have a question, how about NDVI in ur LST vid? Thats video shows you made NDVI with both of B5 and B4, and in this vid u made NDVI with B3 and B4. Which one were better to calculate NDVI?
@ahmedaz307
3 жыл бұрын
it depends on the Landsat version..However, you must look for which bands represent red and nir wavelength and then do the calculation. so if they are at B3 and B4 or B4 and B5, the main problem is to know them.
thank you for tutorial Ask, how to calculate NDVI using Sentinel 2 (A & B) ?
how to get that data of any area which u had in your folder
@gowtham1508
4 жыл бұрын
have you got the data ? if yes where u got.
No sound 😂 How can I know 😂