Exploring a LiDAR LAS dataset in ArcGIS Pro

so here I'm just gonna go over to my lecture 10 folder and in lecture 10 folder once you've unzipped it you're going to find a l a s data Burnaby zip and these are lidar for lidar files from Burnaby British Columbia and I'm just going to right click on that and unzip all of those so what am i extract all and I want to unzip them into the lecture 10 folder into the folder called Las data Burnaby and I'll extract them and in here it has open and then we see a number of last files so each of these is a last file that's your 10 velocity the Burnaby output like so it's gonna bring this over here a bit I just have these two large and this is the sizes of them right here we have one which is 50 megabytes in size the other ones are about 8 5 and about one megabyte in size so just just under 17 megabytes in total for these four last files now if I go to our GIS Pro and I've already connected to my lecture 10 folder but I have to refresh that so it can see the unzipped last data Burnaby folder there it is so there's last data Burnaby and I'm going to output and here are my last files now if you don't see anything here it means you don't have the extension loaded says what a project in the menu licensing and then check for 3d analyst being there if it says no to the 3d analyst you may have to go to configure your licensing options and then find it in here and click YES on it or something to enable that particular extension but we require the 3d analyst extension when we're working with the last files as we'll see so I'll just go back now assuming that's all fixed so I'm just going to bring in this first last file just as an example we can look at individual last files like this and notice the beside the last file D the little icon shows an airplane a bunch of points and a beam that's hard to see there isn't it but you can see that as i zoom in so that's neat that's that way a last file looks and the beam here is showing a scanline so it's scanning from there to there turning the beam beam on and off this is what's a little illustration of what I just showed you on the PowerPoint slide you may get a transformation warning just click OK to that and then it will show us at the last file and if i zoom in I'll see you individual points in there if I click on one of those points it'll give me returned in one of three so for that point there were 33 returns if I click on a different point two of three returns there's even really close to see any individual ones click on this one that was returned one of three three of three three of three etc so each one of these points has a return associated with it now it can be difficult to understand what these are showing and what a return means but if we look at the information in here we have also an elevation so that elevation is meters above sea level so every point has an elevation the darker ones have higher elevations and the lighter green ones and yellow ones have smaller elevations so at the same time to do this I'm going to go to insert in the menu and I should say map sorry yeah insert new map and I want to make a new local scene so this is now a three dimensional scene I'm going to drag the same last file into here transformation comes up again just say ok and it's going to draw the last file in three dimensions for us I'll then turn off the world elevation of ground surface just down here just so I can see everything there we go so I did turn off the elevation surfaces ground and it kind of looks interesting in that when we look at the last file in a 3d scene it looks more nonpoint like doesn't it and that's because it based it aggregates the values of the points and if you zoom in you'll see the individual points again I need to zoom out you'll see how it advocates points of similar value to make it look more like a continuous surface let's have a look through this particular last scene so I'm going to click on my appearance tab one thing we can do is lighting and shading so I don't lighting you can change the change the way that looks and there's nothing wrong with this strength using more contrast or less contrast in your Ross data so you can do some things there so back it we can so we saw the lighting and shading here you can also modify the display limit if you want so depending on how many points are in your last dataset check out the properties of this last dataset we go to the source this particular last dataset has 1 million eight hundred and sixty seven thousand and seventy two individual returns points so right now the display limit is at eight hundred thousand if I want to change that I could change that to a million to put a comma there enter and then it will be dropped the more obviously the more points allowed in the display limit the more detail you get but also the slower will actually display your last data set and if I go to max density as well see that's even slower so I might just feel bring bring that back down to the middle and bring that down to you know eight hundred thousand back to the default so let's have a look through this that again this is a three dimensional data set so I'm going to click on the View tab over here I'm gonna go to profile viewing and I'm going to create a profile by clicking on the create button right here then I'm just gonna draw a line and we'll see the outline of the line it's very very light very hard to see it's an orange and I just did it straight across like this and then I'll double click to finish that and what it's going to do is show me a cross-section in three dimensions of what that looks like so notice it opens up a scene window and now it's drawing that cross section so here I can see that in that cross section I have trees and these look like it's hard to say exactly what they look like but look somewhat deciduous in nature there's some sort of coniferous tree brush of some kind and then here's a building you can see the roofline very easily there's another deciduous type tree over here and you can use the navigation tools at the bottom if you want to move around look up and down on that that particular data set and whatnot and again you can go back and it closed the entire map I need to open that scene back up there we go so that profile viewing tool is only available in the 3d scene this is a local scene and I can do a transect or through any any direction I want just by creating a profile so if I want to go north to south in the street area like that and that'll continue to draw here showing you that north/south profile or cross-section in this scene when I can move around like that I can zoom in or zoom out well I close it again I'm sorry about that I'm if there's a small X in the right-hand side there you close those from so if you have a cross that I'm gonna see up in the right corner a little X that's um what I meant to click and I keep looking to close the entire scene for some reason let's go back out draw now to really get the best view of this we can look at this since it's a 3d view in different directions or forms so you see down here you'll have a navigation in the bottom left corner and there's a little up arrow to control so click on the up arrow that allows us to control so the middle thing controls the the angle of the camera so if I go like that for example I can see out then I can just zoom back until I see my particular scene here I would have it too far and I want to zoom in here I will look at that and then I can rotate around there as well like so and you can zoom in zoom out just what you draw here I might just decrease the amount of points here maybe to 300,000 see if I can get it to display quicker not much so let's go back there back to the defaults now we can also filter out different returns let's say right now the default is all points what if we just want to see ground points well I can click on the last points Pilger just Showground so these are the ground returns let me can see we have a very flat area or very flat regions in the front here and then there's obviously some sort of just going across there in the upper quarter streams stream and this of course was the building outline so you couldn't have ground points there yes they're covered the ground is covered and I can just again just try different views of that and that gives me the ground points the other way I can visualize ground is I can go I can click on symbology here and say show elevation and that's going to draw a triangular irregular Network from the last points using the current filter for the last points which is right here which is ground we can see the same thing if we go back to map to our first map so with this last data set I can again filter out ground in two dimensions now so we're not in the 3d scene but in the 2d scene and then click symbology elevation and it's going to show the elevation roster not mastered but as a tin triangle early regular network and we'll see those kind of triangular facets as i zoom in between points so I can show very detailed ground level information clearly to be more detailed where there's less trees if I filter it to show non ground just trees are anything but ground this is what it gives me here I'm also in the symbology you can look at if you want the slope gets you slope and it creates a slope image or triangular regular Network then here Reds are higher slope and greens are lower slope and even aspect so that's the direction of the slope you can also contour if you have your elevation data for example to go back just elevation I just want ground-to-ground there then I want to let's say show contours or draw contours here I'll put a contour interval of 0.25 I hit enter and there I have a detailed contour map so with the last dataset you can get quite a bit going back to my scene I'll just filter all points back on and symbology back to return there's the point cloud so without the aggregation can you know you can go right through this point cloud so you come far away towards you it's in one a little bit it zoom back in and you can see structures look at that structure here you can really see these structure of an individual tree with this type of a technique a little hard to see there you kind of have to get the right view but here the stem there's um branches going up and down all the way there see the structure of those trees so you can actually see all the trunks in the forest here and then the lower elevation parts right up down here and you can go through the point cloud I can see for example here as I going through that this is these are conifers and they're easily distinguished from deciduous trees is just by the shape of the tree themselves you know so this is a deciduous tree right up here you'll see that assiduous conifer conifer etc so you get a lot of information from last data so the last thing we will do here is look at combining all four of these last layers into a single last dataset so in my lecture 10 folder subfolder last state of Burnaby that we unzip output coming right click and I'm going to say new last dataset so new last dataset and I'll just call it Burnaby like so and nothing happens so in order to add the datasets we have to go to the properties for that last layer so I right click on properties and I'll see general nothing statistics nothing last files nothing so here I have to say add files or add folders so if have a folder with a bunch of last files like I have here I'll just add the folder output so I'll click on add folders I'll go and navigate to my and I have it in temp here might lecture 10 folder and then lastly to burnaby output and I'll just choose output like that I'm choosing a folder and it will put in those last data sets and it tells us some important things here for example the point count of each one so remember that one we've been working with has a million point eight points in it that's quite a large one then there's the other ones are slightly smaller the one are we working if it's quite large because it had that forested region in it the other ones are necessarily have these much forest in them so I have that then I click on the statistics right here and I can see the percentage of points across all my last layers that are within each class classified return so ground has that many low vegetation has that many solo vegetation ground have the most not will not quite the most but the second largest and high vegetation has the largest amount all together and building seventy thousand and then you have some other ones like road surface and no kiss of course depend on what you have in terms of the the region the attributes tab just tells us the term number so we have in some cases up to five returns so five returns is the largest number of returns we'll have for any given point the returns tab tells us how many returns our first returns second returns third returns fourth fifth and et cetera and nothing under classification nothing to worry about there so once we say that we can just click OK and then drag in the Burnaby LASD which is the Burnaby last data set and that's the entire Burnaby last dataset and again we can do the same things that we learned just with a single last data set for example symbology we can choose elevation or return or classified so here we have the values or the classification the information classes for each of the returns according to color likewise in the scene view we can bring the last dataset in there I'll just remove the original last one just so it doesn't cause some of the issues with time to draw go back to catalog bring in the burn and Ruby lost the entire interview last dataset so you can see that there and we can see what we've added mainly as a some areas over here building structures I'm just zoom in a little bit closer down there look upward zoom in a bit more here we can see that coniferous vegetation that is conical you can see some recreation complex here some more vegetation some conical ones and a deciduous tree there as well maybe those are all those are probably all actually um yeah probably a deciduous there and of course you can explore that more certainly there the conical shape of a coniferous tree the oval shape of the crown of a deciduous tree and of course on this region in Canada is the home to the only species that's an evergreen deciduous tree native to Canada our Buddhist men's II we can look it up if you want okay so that's how we look at terms of last datasets

Channel: TheGeomatician

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Id: y0xa3Hh0180

Length: 27min 28sec (1648 seconds)

Published: Sun Mar 29 2020