Download NDVI image using GEE & Visualize using ArcGIS

everyone welcome to the channel and today I'm gonna show you how to download an ndvi image using Google Earth engine and visualize using arcgis so let's get started so now let me explain about the ndvi image so individual stands for normalized difference vegetation index it's a numerical indicator used in the remote sensing and satellite imagery analysis to assist and monitor the health and abundance of vegetation in a particular area the individual is calculated using the reflectance value of the visible and near infrared light captured by remote sensors so here you can able to visualize the formula for the ndbi the ndbi equals to Nar that is near infrared minus Red Band divided by the near infrared band plus Red Band so the Nar that is near infrared as a reflectance value in an ear in front spectrum and rated the reflectance value in the Red Spectrum so the ndva value is typically ranges from -1 to plus one with the meaningful values falling between minus 0.1 and 0.9 the interpretation of individual value is as follow the high negative values that is minus 1 to minus 0.1 these areas usually represents the water bodies or the surface with the little or no vegetation the low value that is minus 0.1 to 0.2 these area might includes the base soil rocks of spare vegetation the moderate value starting from 0.2 to 0.5 these value indicates the moderate level of vegetation cover such as grass linen herb lint and High Valley starting from 0.5 to 0.9 these areas are typically represent the dense and healthy vegetation such as forest or the cropland so now to download ndvi image using Google Earth engine and visualize using rgi's environment first need to import a landsat 8 image into Google Earth engine for that we defined a variable called L8 equals to double eight dot image collection Lancet collection 8 collection 1 type 1 top of the atmosphere so next to get a leap cloud in the next year the image with the least Cloud contamination so for that we Define a variable called image 2015 equals to w dot image L8 dot filter bound point so here the dot filter Bond Point refers to the point function refers to the variable call point so variable Point refers to the polygon with four vertices that is represented here so in order to acquire the landside 8 image of any study region we Define a polygon around the specific study region so we can draw a polygon by using the specific tool called draw a rectangle by just clicking this you can able to draw a rectangle over the study region and which will automatically import a valence at 8 image while we are running this code so next we're gonna filter with the specific timeline for that we Define dot filter date 2015 January 1 to December 2015 December 31st next we are using dot sort cloud cover so we are specifically using this function to get a image with the least Cloud contaminated image those first image refers to the DOT first function refers to to get an image with the least Cloud contaminated image and next to visualize the detail of the Lancer date image video redefine print image 2015 dot to float function so next to compute a normalized difference vegetation index we Define a variable called nir so we are using specifically two bands that is Nar and red band so Nar here represents Arena here represents the near infrared band and the red represents a red band let me show you that so here you can able to visualize this is landsat 8 image it has around 9 bands we are specifically going to use a band Phi that is near infrared and the red band that is here band 4 and band Phi so now let me get back to Earth engine so here you can visualize to compute the normalized difference with station index we Define a variable called Nar equals to image 2015 dot select band Phi so the band Phi here refers to near infrared band and similarly we Define a variable called red equals to image 2015 dot select band 4. so the band 4 here refers to the Red Band and to compute this formula that is so the individual formula here refers to ndbi equals to nir minus red divided by nir plus red that is band 5 minus band 4 divided by Band 5 plus band 4. so we can able to visualize you the formula for ndvi so that is band Phi minus band 4 divided by Band 5 plus band 4. so we are to compute this ndvi we defined a variable called ndvi 2015 equals to Nar dot subtract Red Dot divide Nar dot add red and Dot rename as ndvi so there are to display this result we defined the map.center object image 2015 that refers to the specific variable that is the variable 2015. so 9 here refers to the zoom level and so to compute the visualization parameter we Define variable called ndvi params the ndvr params refers to visualization parameter equals to with a minimum value of -1 and to the maximum Value Plus 1. the color palette here varies from red yellow and green so starting from the lowest individual value to the highest in DVI value of green so green represents the highest in DBI value which represents the forest and croplands the healthy forest and croplands so to next to add this layer into Earth engine we defined map dot add layer in the vi 2015. so in DVI 2015 refers to this particular variable so ndvi param refers to our visualization parameter refers to this specific variable and last to Output the layer name as ndvi image 2015. so to add our Lancet 8 image we Define map dot add layer image 2015. so image 2015 refers to the specific variable that is image 2015 the reservoir landsat 8 image so now to download now to download the that is our ndvi image two over Google Drive we Define export dot image dot dry image ndvia 2015.2 float function So to avoid a flow to avoid a whole numbers we are specifically using the data type called float function next for description we Define ndvia image 2015 and the spatial resolution for the Lancet 8 image is around 30 meters for that we Define 30 meters our region here refers to the point there is a variable this specific the specific variable is called the point it is a polygon with four vertices we defined as a variable point so next to the max pixel value we set to 1 is to 10 power 13 as our Max pixel value so now let me run this code so go to this option called run script and click run script so now let me minimize it so now we can able to visualize we have two different image one is the Lancet 8 image and second is the ndvi image so now let me make some changes to our Lancer 8 image go to the option called this particular option select to three and four and select the custom as stretch to Sigma and apply so you can arrange this band you can have different false color composite now let me make a true color composite four three and two and apply the stretch a customer stretch Sigma 2 and apply so now you can able to visualize the true color composite of our Lancer 8 image so now we can able to visualize our true color composite similarly we can visualize our ndvi image so now let me turn off my polygon boundary so go to this option and you can click this button it gets turned off so now you can able to visualize here the high dense screen here represents our agricultural land and the forest and similarly the color here there is an yellow and reddish color represents the water body so you can able to visualize the water bodies being represented in this specific color so you can visualize the water body the water body is being represented in yellowish red color and similarly the vegetations has been represented in the dense green color so this is the flow direction of a water that is a river you can able to visualize that so you can able to visualize towards eastern part of the study region has a lower vegetation compared towards the western part of the region so western part of the region has a very high ndvi value indicating a higher forest forest or agricultural areas compared to the eastern part of the eastern part of the region now let us download this image download this image and visualize in our gi's environment goes to go to the tasks section so now we can able to visualize there is an option called individual image 2015. so now let me click this option called run so now a new window has been popped out saying it's uh initiate an image export the task name is ndvia image 2015 epsc 3857 spatial resolution of 20 meters so we're going to export to our dry so you can also try in the cloud store region Earth engine assets so now I'm gonna export to our drive that is our Google Drive so you can also enter your folder so far the file name will be in DVI image 2015 and jio Tiff so it's going to be in the geotab file format so now let us run this code click this option called run so now we can able to visualize here we have our ndvi major 2015. I have already downloaded my one of this ndbi image 2015. so it took me around six minutes to uh export to my Google Drive so now you can able to visualize the task section that is we have our submitted task the ndvi image 2015 has been exported to our Google Drive so now let me open my drive so we can able to visualize let me open my drawing so this is my drive section so now let me refresh it so now you can able to visualize we have our ndvi image of 2015 so now let me download this right click and click this option called download so now we can able to visualize I'm going to save this file called NDB image 2015. so now let me save this so the ndvia image is around 45 MB so now let me open in rgis environment so now you can able to visualize this is an rgis software rgis desktop so now let me uh add this file into arcgis so to add the ndvi image into arcgis go to the option called add add data so now you can able to visualize we have a ndvi image so this is my this is a ndbi image I've saved in the folder the Google Earth engine so now let me click this and click this option called add so now click this option to create a permit for ndvi image 2015 yes so image is getting exported to our arcgis so now we can able to visualize this is our ndvi image we have downloaded from Google Earth engine so we have the range starting from minus 0.62 plus 0.8 so now let me add some color variation to it so click this option so now you can select your color Ram so now also going to select the specific Color Run to it let me select this so now I'm gonna select the specific color Ram so I have selected this color let me click ok so now you can able to visualize the high values that is here indicated that is 0.8 indicated in blue color all the blue color indicates a very high ndvi value and comparatively the low value that is minus 0.6 here represents the water body so you can now visualize here so this specific region will represent the water body of the study region that is indicated in in the yellow color and similarly the high in DBA value here represents our forest land and the agricultural land that is indicated in blue color which is shown in there here in the high value of 0.8 so in this way you can able to download the the ndvi image that is you can download the ndbi image from Google Earth engine and you can visualize using arcgis environment so now let me get back to Earth engine so in this video we have shown you how to download the ndvi image using Google Earth engine and visualize using arcgis environment so thanks for watching and please subscribe to our Channel and give us a like

Channel: Terra Spatial

Views: 1,103

Keywords: Google Earth Engine, NDVI, Normalized Difference Vegetation Index, download NDVI image using Google Earth Engine, NDVI analysis in Earth Engine, ArcGIS, Visualize NDVI in ArcGIS, NDVI Analysis, Google Drive, Earth Engine, GEE

Id: rpEEM56eTWs

Length: 12min 37sec (757 seconds)

Published: Tue Aug 08 2023