Create a DEM and Contour lines from Google Earth on QGIS ✔️✔️✔️

i'm a hydrogeologist my model in life is think out of the box my name marcel my experience ground water and soil contaminations i'm the creator of jlrgb a channel of geographic information systems gis geology hydrogeology and contamination the purpose the objective the goal the intention the target the desire share my experience and acknowledge to create eight points of discussion the jail rtb community promote the use of free and open source software a free digital society provide technical advice to environmental companies an opportunity for professional growth [Music] google earth vs slider digital elevation model dem and content alliance about this tutorial this mini course consists in three video tutorials in the first one you are going to learn how to create a digital elevation model dem with quantum gis using data from google earth in the second one you are going to learn how to use last tool to process lidar data to create a dem with quantum gis also you are going to see how to get the contour lines from both models the third one is going to be a comparison between the two models and we will have a discussion about the currency of the ground elevation from google earth data google earth part one what you are going to learn in part one how to export a shape file to google earth create a kcm file with the elevation data from google earth export the kmc file convert the kmc file to text file open the text file with quantum gis change the coordinate reference system crs from wgs 84 geographic to nat 83 zone 11 projected create a dem based on triangulated irregular network team with quantum gis contour lines extraction let's go to do it first let's go to see what is going to be the work area to do that one i'm going to load a raster file it is the digital elevation model that already i created with the lidar information is this file here open and add close and as you can see here there is no uh reference coordinate systems as designated to this uh digital elevation model then just i'm going to click here and i'm going to select the not 83 utm sum 11 because that's the the coordinate reference distance the lidar that i use then okay and also i'm going to change here the reference coordinate systems for the project and apply okay now what i'm going to do is add the satellite image for this area and i'm going to use the equip map services plugin if you don't know how to install this plugin i'm going to leave a card here at the top or right corner of your screen that you can hit and watch the video tutorial to install this plugin then google google satellites and this is the area we are going to work i lo added the digital elevation model just to create a shape file with the interested area however in this video we are going to work just with the google earth data and we are going to create this digital elevation model from the lidar information at the second video then to create the shape file with the area of interest we are going to go here add a new layer and it's going to be a vector layer then oh sorry layer create layer new shapefile layer then here name is going to be i already created a file and you can create it like this new folder and then go inside the folder in this case it's going to be area the name of the file and it's going to be a shape file save and here is going to be a polygon and the reference coordinating systems as i said before is going to be not 83 zone 11 this one okay and the rest of parameters is okay okay and then press this pencil here to edit the layer and we are going to select this one and we are going to create a rectangle with three points then the area is going to be from here to here and to here something like that then it's going to be one and okay [Music] and now press the pencil to finish the edition save now what we are going to do is export this file to google earth i'm going to open google earth [Music] close then go here file import go to your folder is this one say file here select shape because you are going to load a shapefile so that the file we created the area open and say yes and that one it's okay and okay and for this one it's going to be area one for example save and now it's time to edit this one it's this file over here we can go to properties and here style you can make this one transparent 0 and you can change the color of this one for a red one for example okay and make this one thicker maybe maybe two okay and that's the area we are going to use in google earth now the thing is you need to have this option over here click because as you can see the shape of the rectangle change when you click this option because the rectangles add up to the surface of the terrain you can see now how we change and now it is necessary to have this option click because if you don't have this option as you can see here at the bottom for elevation that is zero even if you are moving it doesn't change any value that's the reason because you have to click this option here terrain to see how the elevation change now what we are going to do is a create a grid with the elevation of all this area then to do that one go here press this option over here add a path [Music] and then put any name i'm going to leave here path and with this windows open you can go here keep the left button of your mouse press and then move and as you can see it's creating some points and that's the elevation we are going to use to create our digital elevation model from the data from google earth okay as you can see for example if you make zoom and you start to do the line over here the density of the points is going to be bigger right and if you take out and go to this kind of zoom the density of the points is going to be less even if you want less density you can go back a little bit and do for example from here it depends uh how much points of information you want for your area but i believe something something like that is good enough [Music] in my case going to pass the video faster [Music] okay that's it don't worry if you pass the limits because he has to have an idea about our working area right i'm going to add some more points over here but that's uh pretty good i believe we have a lot of points of information related with the elevation then when you are done just press ok and that's the the file we get then press here right button of your mouse and save place us and then select a folder in this case i'm going to go here this folder i am going to create a new folder that is going to be google earth and i'm going to add the file here inside as a path save the next step is to convert this data on a text file to do that one we are going to use this website i'm going to leave the link at the video description then go here to browse select your file in my case the file is over here [Music] google earth is this file open and now what we want here is a plain text then press here convert and add elevation [Music] and wait until the process finish here is the file that we can download okay [Music] the process is finished is this file i'm going to cut this file and i'm going to paste in my folder open containing folder and i'm going to paste here in google earth paste as you can see you can open this file with notepad that it comes by default in windows 10. one interesting thing that you can see here is the coordinates it's in latitude and longitude and the elevation is in meters but when we was doing the process we was using utm coordinates as you can see here are the tools options we have universal transverse marker we are we are not selected this option because if we selected this option we have here a latitude and longitude but it was not the case right but anyway here at the data it shows the latitude and longitude and now what we want to do is convert this information in utm coordinates in that way we can measure distance on the map in meters in order to change the reference coordinate systems i'm going to copy all these numbers and paste in a spreadsheet i'm going to use openoffice openoffice it's a pretty similar software as a microsoft office but this one it's on three and open source i'm going to open the spreadsheet i'm going to copy all these numbers here edit select all edit copy go here ctrl v to page okay i'm going to eliminate these two columns delay columns and i'm going to save us and i'm going to select this kind of format csv and then the name is going to be one and save [Music] and keep the format and okay okay and i'm going to close this one now i'm going to open a new quantum gis project and i'm going to add that file i'm going to select this option go here and open the number one okay and here i'm going to select this axiom csv i have to make sure the x is longitude and y its latitude the referent coordinate resistance is good and this is the data its content in our file now let's go to add and close and now i'm going to export this file because as you can see if we go to ato table we have here the latitude the longitude and the elevation emitters but we want here the utm coordinates then to do that one click right on this uh file go to export save feature as leave this option over here the name is going to be number two save then we have to change the coordinate systems and we want this one not 83 udm sun 11 okay and this is very important for the geometry we have to select x and y and the rest of the parameters is okay then press ok and let's go to check the attribute table and as you can see now we have x the coordinate x and the coordinate y for the utm and also it keep the latitude and longitude and the altitude let's go to close this one and let's go to close this project this card and now let's go to work with the other project this one over here let's go to what the new file we created is going to be this option here open is going to be number two open this this kind of file this one make sure here you have the x and y because now we are working with latitude and longitude and here select the proper utm coordinates is this one and at close and the next step is to convert this file to shapefile then let's go to export save as a feature in this case we are going to select this one say file the name of the shape file we are going to keep at the shapefile folder and it's going to be elevation and then we can save and the coordinate resistance is good and then okay [Music] and we can take this one out already remove [Music] and we are going to do the interpolation with the shape file in order to do the interpolation here you have to write in and that's the interpolation we are going to use double click select the elevation is this uh file over here and the add the attribute you want to interpolate as you can see here when i try to select i cannot see any attribute that it's a problem related with the attribute table then we have to do some modifications to do that one let's go to go here open attribute table press the pencil to edit the attribute table then go here to the calculator and here we are going to add a new field the name is going to be elevation like this one and we are going to select a decimal number and here is going to be just four numbers precision is going to be one because we have four numbers and one precision one decimal over here and then here we have to go to values field and values over here select the altitude double click and then here multiply by one and okay and it creates a new field as you can see in that one it's elevation then close the edition save and we can close this one and if you go here properties and fields the problem it was the altitude it has this type of data and when you try to do the interpolation with team it doesn't recognize this one as a real number that's because we have to select the real number over here for the type of name okay to in order to the software can recognize that one as a number now we can double click here select again the elevation and now the attribute you can see elevation then add this one is going to be points and for the extension we are going to select the second option select extend on cavernous and i'm going to take this one out and i'm going to take this one out and this one out and i want a rectangle inside the points okay i want something from here to here something like that is good okay and then i'm going to save the digital elevation model save file and i'm going to save here at the google earth folder it's going to be them save and run now i'm going to pass the video faster [Music] okay the interpolation is already completed then we can close this window and we can take this one at the moment and make some modifications here at the properties go here to single band save the color and select a ramp of color [Music] here for example this one apply okay as you can see over here that then it's a temporary layer then let's go to save this one export uh save as keep in geotiff and we are going to save here as the google earth folder as adam save and the reference coordinating assistance is good the extension is good everything is good and okay and let's go to complete the process it's going to take a little bit of time i'm going to pass it faster okay the process is complete now we can remove the temporary layer remove and do the addition over here properties as we did before and apply and okay as you can see in this folder we have the then and also we have this then file is this one over here that it shows the triangle it's interpolation to take this one out and the points out if you want to know more a little bit about this kind of interpolation i'm going to leave a link that it explained a little bit about the this kind of interpolation over here [Music] and that website is from quantum gis [Music] also what i would like to show you it's a little bit the process with it because we take a lot of steps and could be a little bit confusing and i created a graph to make a summarize is this graph then we started with google earth where we capture all the data elevation in a kmc file then we converted this file in a text file using this website over here then we convert the text file to a scv file using the open office with the spreadsheet and then we open this uh cs5 with quantum gis and all the time we was in the same uh reference coordinate systems then we pass in quantum gis using quantum edges from this file to the same file but now we change the coordinate reference distance to geographic one to project one then with this file we pass to shape file also with quantum gis to make the interpolation with the shape file hopefully it helps a little bit to understand and repeat all the process because it's a little bit complex now let's go to see how we can create a 3d model using quantum gis and the plugin we are going to use is this one and i'm going to show you now how to install let's go here to plugins manage and install plugins you need internet connection then close here and you have to write here yes cool gis 2 and is this plugin just select the plugin install and you can use it and i'm going to take this one out and i'm going to keep this one go here this one select this one and mark this option and this one is the 3d model then you can move with your mouse okay there are different options just play with this option and now let's see how we can extract the contour lines just go here to raster extraction contours select the them because you want to extract the contour lines from the then the interval between contour lines 10 meters is good the attribute is elevation that's good this one it's okay and here i'm going to save the file inside the shapefile folder okay i'm going to leave this format that's okay and i'm going to save as a control line contour or contour google earth that's it save and run and close [Music] and that's the final result that's the contour lines for this area we can edit the contour lines here are the symbology a different color a black one for example on number three here and it could be this one a dashed line apply and okay we cannot see too much here let's get to change for a different color for example right one apply okay and if you take this one you are going to see the better then also we kind of did the symbology to add the values for the elevation at labels here single label select the elevation here and let's go to put a buffer here for the placement on the line apply let me see how it looks like no not this one this one apply okay right there the buffer has to be bigger for example three and here for the text and we can put wall apply and okay that's the final result for this model [Music] and see you on the next video where we are going to work on the same area but in that case we are going to create a digital elevation model using a lidar data where you are going to see that the topography the digital elevation model the accuracy it's so big and the quality of the contour lines are going to be totally different okay thank you very much for watching and see you on the next one [Music] [Music] [Applause] so [Applause] you

Channel: Geo RGB

Views: 14,798

Keywords: contour line, contour lines, contour line google earth, dem google earth, topographic maps google earth, countour lines google Earth, DEM google earth, google earth and QGIS, create contour lines with google earth, digital elevation model QGIS, 3D terrain model, 3D terrain QGIS, Google Earth Terrain Model, Google Earth DEM, Topography model, QGIS Model Terrain, Surface digital model, contour lines QGIS, Contour lines Google Earth, generate contours and dem from google earth

Id: NXGKBeb8tR8

Length: 28min 49sec (1729 seconds)

Published: Sun Dec 27 2020