QGIS and LiDAR LAStools

hi this is karen o'brien and we are going to talk about some lidar data and how to manipulate and get lidar data and how to turn it into data that we can use for flow 2d using either gds or the qgis plugin so let's start with a couple of things that we need to get through this course or to this lesson so we need last tools last tools is a program you can get it online from rapidlasso.com let's see if i can find out see if i can remember who created this tool um martin martin eisenberg is the developer of this tool and it is really awesome now there are plugins for both qgis and arcgis that will also use some of these tools in laz tools but i'm not i'm not going to do anything with arcgis other than show you some of their help files that kind of help identify and define lidar i don't know how to use laz data in qgis or lidar data oh sorry in arcgis so we're just going to skip that so if you want to get this you just go to last tools and you just download it once you get that downloaded i'm going to grab my download folder real quick you'll see that it comes like this comes in lasttools.zip and then when you extract it you get this guy right here and you can just pop this guy straight into your c drive that's kind of the default location where you want this i put mine on my d drive because my c drive is kind of doesn't quite have as much space so i'll show you then once you get into qgis you can also get the last tools plugin so if you click manage and install plugins and you go to all you can search laz tools you'll see that there's a couple if you actually if you just search the word lidar there's a few different things that you can do with lidar different lidar plugins but i only know how to use laz tools so i install it it gives me version 1.4 and it gives you a bit of a change log which is really nice okay then if you look at my installed and delete everything you can see that last tools is right here all right if you want to do this you also need the flow 2d plug-in i'm using 10.26 so if you need 10.26 you're going to have to just reach out to me because it's probably not going to officially release it till the end of july but people are already using it right now so i'm going to close this because everything we need is is already loaded now if you didn't put laz tools on your um on your d on your c drive then you need to come in here and you need to um go to that so that was sorry let me try that again so you go to settings and then you go to options and then down here on processing you go to providers last tools and then you can just double click inside here and it will bring up a browser so you can browse to the last tools folder and as you can see i've already done that so i'm just going to cancel out of that now we're kind of done with qgis for a bit now let's talk a little bit more so that's how you do that's all you need to do to get ready to get laz tools going now let's talk a little bit about lidar so what is a last data set so that's kind of where we're at right now these last tools are going to work with a handful of lidar data sets but mostly what you'll see with a lidar data set is a dot las or a dot l a z a dot l a s or l a z is just a zip dot l a s and if you see anything other than that like a dot z l a z or something like that you might not be able to use laz tools for that okay that's a proprietary thing so if you don't if you do see something like that i just recommend doing a search and how to you know utilize that data it probably requires a specific um program to utilize it um all right what is lidar data so lidar data is b is just light let's see it's light intensity i can't remember what it stands for but you can look it up yourself it's not really that big of a deal it's not important that we know oh here we go light detection and ranging yeah light detection and ranging so basically you're going to get a sensor and a laser on a a fixed or rotational wing aircraft could be a drone an airplane or a regular plane and that's going to fly these uh straight lines across the ground and then it's going to shoot the ground with the laser you know like millions and millions of times and um the the paths that the laser is going to overlap on the paths and so every time it does a swipe it's going to kind of hit every point you know more than once possibly okay so you can see here that you get your uh you know once you see your point it might bounce back at a different so you you're gonna let's just talk about the attributes of this data sorry so the attribute is the return strength uh the return number for a specific spot number of returns the point classification is a post-processing we're going to get back to that in a minute the edge of the flight line the color that goes along with the aerial images that the camera is also taking the time the the time stamp of the lidar and the scan angle and the scan direction um and so those are all the attributes that come with the data and then they are um put into a file what's called a dot las or laz and it's a binary file so you can't just read a binary file you know you have to either you have to do some post processing to get that data into a format that you can read so the um the company that flies the data will process all of the data to identify the buildings power lines birds trees things like that and then they will make categories or classifications of all that data and that's what the point classification system is so point classification is pretty simple uh the ones that we're kind of interested in is to ground obviously um and then we probably want to well we'll see in our data set what the difference is between 2 and 12 and 1. and so ones we might be interested in would be ground building road surface and bridge decks those might be something that we would be interested in and you can export this data per by category which is super cool uh because you can like export all your buildings or export all your roads and then utilize and then use that to help you define you know the stuff that flow duty also uses uh n values for roads you know vegetation density for land use things like that um let's go ahead and take one more thing i guess that we're probably good yeah i showed you that and then we talked about that so we're good there all right so now that we have um some now that we've kind of know what lidar is we've kind of very rudimentary diagnosis of what lidar is let's talk about how can you get lidar data so for the most part someone's going to be like okay here's your project here's your data and you're going to do the project and the base data that they give you might be lidar if you're in the united states and you're doing an urban flood study on a big city you're probably going to have lidar data sometimes the entire county will have lidar data sometimes the entire state will have lidar data but it's getting more and more common throughout the united states and in many places around the world too now this lidar data is coming in a uh this is iowa they did the entire state so important things about iowa that you are about this data set that you need to know first off is that you can sort this data by watershed or county or city or whatever and download it you don't ever want to download more than you can then you need because it's ridiculously huge files so important the most important thing about this getting this data is getting this tile so this count them but it's really not that important but that's how many lidar data sets we have for the state of iowa and if you right click on this and you go to properties you can see that you have [Music] the coordinate system that this shapefile is okay so it's uh it's got its epsg code that we use in qgis nat 83 utm zone 15 and it's in meters that's important oh there's 36 999 of these tiles too cool all right so that's important to know because that's going to make because when you load that into your project you want to make sure that your project is also set to that and let's turn that off because we don't really need it right now i also got the counties for iowa and i got you know some watershed boundaries and things like that so let's go back to here and let's take a look at this ashton creek and uh okay sorry i've got it i have to kind of reset this because i already did this so let me try that again i'm going to set it to watershed and then i'm going to set that to ashton creek and when i do that it's going to update these results right here now if you don't need if you have data from some other system or some other server it's not going to always be the exact same but it's usually going to have some kind of data viewer that you're going to be able to identify your watershed or identify your region and then you know break out an area by selecting an area and getting the data for that area this one's a lot more uh rudimentary than that it doesn't give you all those kind of cool um you know selection by shapefile selection by kml etc so it's not quite as good as like earth explorer on usgs all right let's go but it it's so easy to get the data so as soon as you get the data it's going to give you uh the list of the files that you can take and and again we don't need all of these that was just all the files for that one watershed now the last files are are not filtered by any means they're just classified last data of course they filter it and take out bad points by the post-processing system but they're not filtered in any other way and so and then the ascii data that they give you for this site is filtered it is just filtered to category two all right now um so let's see uh you oh things you need for this data so you do need to uh download and install the 7zip decompression software and you can get the link here and if you have like more than 100 files or you don't want to click on these individually you can also use download them all which is an add-on for firefox and works really good and i use this on lots of other things so if you have something that you have to download a bunch of stuff from this download them all is awesome because it gives you the opportunity just to kind of select all these files and then click download them all and it'll just download what you selected now i'm not going to do that right now because we don't need them all because on the test that i'm going to do i'm going to just use four of these so i would take the four that i wanted from the list and then download them into let's get to my project here into this guy right here and also wait this is definitely the wrong project folder sorry about that i copied this over to the c drive for a reason and we'll explain that minute later but i need this on the c drive it's important if you're going to be using the flow 2dq gis flow 2d plug-in processor with 4 lidar data you need your data all of your data to be on the c drive um here we go here's my last data and i let's just sort this by type real quick and these are the files that i extracted so i only need four of them and what i'll do now is show you the four that we're going to use by zooming in on the project domain so i just created let's first of all let's get rid of the counties and let's bring up the tiles and you can see the names of the tiles right here those are the only files i need so typically with the flow 2d project you might have anywhere from 10 to 50 to 100 of these and so you're gonna be processing things are going to take time to process but good news is this laz program is pretty fast this last tools this really does this fast so that's good for us now um let's see so these are the four tiles we want we can ignore all of the other data you just want to get enough of these tiles to cover your project now there's some other super cool things here that we can do like obviously we don't need all four of these tiles so we can actually make some corrections when we process our data to minimize it to just this area now remember this data was in utm and meters so you know in the united states we don't really use utm we don't really use meters on flood studies we kind of go for state planes so i'm going to do some of the processing using utm and then i'm going to show you how to convert the data to state plane and then we'll see it again on the state plane side but a lot of these um ways to use this data is uh just easier to start with the base data sometimes it's easier just to start with the base data and then convert it and other times it might be easier just to convert the data so we're going to try it both ways and then that might require a second video because it's probably going to take too long no problem now let's talk a little bit about laz tools uh so here is our project and i should have one here somewhere that says bin and i don't but that's okay we'll get right back to it so i'm gonna go to my d drive and laz tools and bin okay so this is my last tools program as you can see it's got a toolbox for qgis and a toolbox for arcgis it's got some example scripts that are really cool to show you how to set up like pipeline scripts that will do like a series of tools and process the data in different ways and um let's see oh something important so let's get in here real quick now some of these tools are open source and you can use them without a license and some of these tools require a license so if the cost and pricing of rapid i'm sorry of last tools is here so if you need the blast uh one you can you can purchase it here using a paypal link and you'll see why you want to purchase it in a few minutes if we can get to the blast to to dem part if not we'll have to do that in the next video all right so let's go ahead and just show you some of these first of all each one of these uh processors that we're going to use these little let's just call them components will have a readme file associated with it and in the readme file not only does it tell you how to use the tool or a little bit of what the tool does but it gives you some examples of how to use the tool and it um let's see and it gives you a list of the command lines arguments so you these are the arguments that you can pop into the command line uh now there is a gui so if you use the gui i'm not oh sorry i don't know why that okay there um so if you use the gui i'm just gonna say right now that this gui is kind of a pain in the neck uh it's not a bad system it's like it it does a really good job of viewing the data and loading in the data but what's really bad at is like every time you click on a close menu it just closes the whole program down and it never remembers what you uh we're looking at so you'll probably get tired of the gui right away and instead you'll want to um do things from the batch script instead so we're going to try to show you how to do all that like in this class too let's start with uh qgis and doing the processing from qgis so we have you can use the last tools and use the last tool gui and that's fine it's actually really good way to do things once you're starting to learn laz tools or you can use the last tools from the gui by using the processor toolbox so that's this guy right here so if you can't see this guy right here go to the plug-in menu and make sure that it's installed and checked and then once you're in here well you see that the last tools are all right here but once you're in here just search the one you want to do so the first one we want to do is last two text well let's see if we can do last dem last two dem let's just see what lasted dem does well we need text data so i'm not super duper duper concerned about yeah let's do last detect let's stick with the program here last two txt i hate when i shift gears and totally change my method right in the middle of a class and then something doesn't work so let's not do that all right so run the new 64-bit executable that's what we'll choose here i don't know what verbose means it's something to do with the way the script is written so i'm just going to leave that unchecked because i don't really know how to use it now here's the input file that we want let's just take let's see which one do we want oh okay let's do one cool thing about this processor is that you can still get in here and see things so i think we're going to take the 02784704 because it has some features i want to show you okay so i said 02784704 and we are going to convert that to text so i want to delete that file right there and par string let's go ahead and go with x y z obviously that's what we want but let's go ahead and add intensity and uh class here and uh line parameters no don't want anything there now let's get said save that to the output file and we will just choose this guy 704 but take that off and call it txt so this is just processing one individual file so that we can just review and look at the file i'm gonna go ahead and click run on that and wait for it to complete and it says results none um hang on a sec why does it say results none now that's perfectly fine i don't i think it's because it didn't load any layers would be my guess it is not going to load the data for you it's just going to create it for you all right now i opened this over here on the other window txt this is the file that we just created and i'm going to open it here and so you can see that uh it's space eliminated data x coordinate y coordinate z elevation now remember this is utm and this is meters this is the intensity field that i was telling you about the strength of the sig of the returning light signal and i don't really know what the range of data is uh so i'll just ignore anything about that and this is the classification uh remember ground was 2 and 12 was i think i can't remember what 12 was but we only have like ones twos and 12s in here so we don't so i'm going to show you what this data looks like in a minute and we got um let's see is that 2 million 34 2 million one hundred and twenty one 121 um lines of data points so let's let's import that into qgis and just take a look at it so if you use this guy right here you can import text data into qgis now i'd not recommend that you import all of your text data into qgis because ridiculous amount of data and i mean maybe if you indexed it or something like that but it's just you don't need it but i want to show it to you because just to see what the difference is between uh the data with the categories and the data like that has a filtered by category so i've already set this up once you point to your file it is a custom delimiter space to limited no headers no field names yes detect field types yes trim fields yes discard empties field one was x field two was y field three was z although i don't really know why we need that i just choose i just picked it because it was available um and click add and that should be okay now that's done and now i'm going to go and close it and i'm going to go back here to this last text i'm going to do the same thing i just did except this time see that was 74 and this time i am going to add a command let's see i see just so that the data is exactly the same i'm going to add a command to to filter to keep only the class of ground and then i'm going to save this to file but this time i'm going to change the name slightly to um ground yeah that works and run and we'll wait for that to complete it shouldn't take but a second because it's actually exporting less data and that one is done so we can now close it now let's do the exact same thing and load this data except i want this one to be on top so i'm going to put my cursor right here and click the project domain layer i'm going to add this by grabbing it and everything should be the same so x y z and i don't think i need to change everything else just click add and close okay now let's let's um let's see let's see which one has the most data this one has the most data right here so i'm going to double click this to set up the symbology and let's do sorry about that that thing keeps clicking um let's do c we need to change this to no pen and let's 0.5 and then change the symbol to graduated field 3 um color can be spectral and classify and then we'll just just color this data a little bit so that we can uh kind of get an idea of what the elevation looks like from the points and i'll click apply and okay now actually let's see yeah let's click apply and okay and then i'm going to copy this data here i'm going to copy this style and i am going to paste it to this style okay so now i want you to just notice what the difference is between these two data sets so the full data set has some strange things in it right like what's going on over here why is that not why is that not completely flat why are those bright blue and why do we have bright blue things over here well it's because there are trees and stuff in here now the trees are let's see if we can zoom in on one and get and figure out what these trees are that should get us there now i'm going to hit the id tool i don't know if this is going to work very good or not but i'm going to try it i'm going to hit the id tool on this guy right here make sure you're on the active layer and then click it and i want to see what the category for tree is okay the category for tree is one in that case and then the twelve the category okay then you see here we also have let me zoom back out and let's go over here to where we have some buildings whoops i might have messed that up nope i'm good well let's just wait for it to yeah it's it's down here okay and let's grab the categories of these buildings and the building category is oh well you know what i'm like i probably messed that up the building category is i only needed one of those so also one so it looks to me that anything that's not um ground or overlapped i think 12 was overlap ground or overlap is um is is just categorized as one okay now check it out when we take off that you can see that it filtered it out and it only gave us and it took the buildings out and it took the um trees out and so this data will just be filled in from its neighbors when it gets interpolated to the grid it'll just be like nearest neighbor type of thing um okay so that's how lidar data works now if you had um some kind of cool tool like global mapper or arcgis you would be able to get down in and see like power lines and birds and you know curb and gut you could align and assign curb and gutter so uh we're not getting that cool with this data we're not it's not that robust but we don't really need all that anyway so we're just going to use it for what we need it for so i'm going to go ahead and turn these off and i'm going to remove them because like i said we don't need this data in here so i'm going to remove the layer and the next thing we're going to do is a let's get rid of this identify results a batch of the same thing we were just doing okay so check this out if you hit the last to text tool and you come here and you hit the run as a batch processor this model that's what this is it's a it's a model that runs like a series of tasks and you know like finding your files um setting up all the parameters and then executing each and each file individually works pretty good um and it's pretty sweet so ah now here's the deal though you can either start filling all these in automatically and then save it once you've got them all filled in so i've already done that so i'm just going to grab this guy here and i am going to open the last to text json file because i already saved that from the last time i did this so the cool thing is that it fills everything out for me because i'm done with it all right check now so i don't again i don't remember i don't know what verbose is i did a little bit of research on it but i i didn't really need to know what it was so i just ignored it uh yes on the run the 64-bit filter now let's see if i now normally these are all um default no so i can change the first one and then auto fill down to change the next one or i can autofill from an expression which is pretty cool not so much for this one but for other ones uh do not use the last gui with this it's just a pain and it doesn't seem to work very good i don't know it didn't work for me so maybe it was just me and then input files these you kind of have to get individually um or you can kind of copy them like one of the ways to copy a path is to uh right click sorry shift right click and copy as a path and then you can just pop that in here or you can use this guy and just grab it like that and this is your input data so we want that to be input parse data this time we only want x y z because i don't need all that data and this time um i'm going to hang on a sec let me get this over here so i can make it a little bit bigger i'm going to add an additional command line parameter from the list of the from the readme file list so if you don't remember this is the last text so last two text is lasted last last 10 last the text the last detects readme is here and i'm going to grab some of these extra commands these additional commands so you can filter based on the coordinates and that's what i want is the filter is to keep the x and y within this box within this bounding box i also want to filter by class so i want to keep class 2 and that will be this guy's this guy right here keep class 2 okay so i have added these commands into this everything is space delimited and i've added these commands in here let's take a quick look on this and how i developed this just to show you so i'm going to grab a blank notepad and i'm going to just put this in here because it's a little bit easier to read so very simple keep underscore x y and then this is let's see we got to get i think it's x min y min x max y max and uh let me get a quick um let me just confirm that i i'm sure it's fine but okay so let's go back up here to keep x y yeah x-min y-min and x-max y-max and and like you can see it's space delimited all right so let me show you how i get this super super easy with qgis to get these um coordinates and i highly recommend this okay so if you come to qgis and you let's just get this thing out of the way for now because we're we're gonna do all our work in that notepad file for just a minute all right so if you come to qgis and you're on your map i don't know i always kind of pick up this guy and i just come down here uh and make sure that i'm kind of outside the boundary of that project domain right click and i can copy the coordinate now i'm going to go back here to this guy and i'm going to hit enter and i'm going to paste my coordinate and then i'm just going to clean it up a bit okay um let's see so three we can just do that and this one would be like i don't know like nine five nine zero it doesn't matter this is the minimum data so it can be nine zero so for the maximum data you wanna like maybe raise that up to a ceiling and the minimum data drop it down to the floor and it just makes the data a little bit easier to read same thing to get the max you just put your cursor up here and make sure that you're you know slightly past the boundary right click copy coordinate and go back to your text file paste that in there and same thing so now this one is we're going up to the ceiling so that's 60. it's not really that important i just i just hate coordinates with uh and then this one would be like 50. and then of course that's in meters and then you can copy that and put that in here inside the command window and take the entire command make sure that there's only one spaces make sure there's only one space i don't know that it's important but i'm pretty sure it strips the spaces out uh it strips and splits the data when it reads it so i don't think it matters how many spaces there are because of that strip and split um function that the data parsing does so you can copy that and you can come back here into this command line and paste it in here and then again just fill down because it's going to be the same for every one output data is also easy so basically for the output data i'm just taking this copy and then i do this um and i can output to paste and then txt and then save that so i already did all that so i'm just going to just check them real quick to make sure that they're the right ones 704 uh 84706 804704 804 706. so these are all good and then when you click run it's just going to run these in batch in a as a batch process individually and then save them so first thing we need to do is come over here and delete all of these and that should be good and then we want to play that or run that and then over here you should start to see these guys filling in so you can see those filling in so you know that they're getting processed and then over here it'll tell you like when it's done it'll tell you that the execution was complete and how long it took so the cool thing about this is you'll like if it's a lot of data you'll get to see the progress bar and you can track it that's pretty sweet um now but what we want is this log um okay so what we want is this guy right here the last tools command line right i just want yeah this guy right here copy and then i'm going to pop that into a text file because i can then come back and um replace some of this data and and then i can run this as a bat a windows batch program so i'm going to grab this here let's see i should already have one in here sorry i'm in the wrong spot give me a second here so this is the last text.bat i'm going to open that in notepad and let's do that and you can see here that i have the uh location of the batch file or the location of the program and then the um other information and then we can just replace this with like a path a list of projects but we're not going to do that yet that'll come later so there's three ways to process this data one is through qgis one is through the gui and one is through the batch um files so that's what we're gonna work on here okay let's but all but for now i i just want to get the data ready for flow 2d so i don't care about all that extra stuff just yet because my my idea is to get this ready to um to interpolate to the grid and this is what i need to interpolate it to the grid now um if you wanted to load these back into your map what you would hopefully see and i'm going to do one just just so we can see what that that filter did for us okay so let's see um this guy yeah there we go and let's grab this one and i don't think we need it just one two add and close and you can see that it didn't give us the whole tile it just gave us the data that we needed so it's going to go way faster so we don't have nearly as many data files okay so i'm just going to remove that and um okay let's go with the the gd the flow 2d tools okay now let me zoom to the project domain um so you need a grid so i think i have a grid but i'm going to do it anyway so here's the deal i'm going to show you a couple things because there was a bug in this version of the plug-in so if you create grid and you use an external polygon and we're going to go pr for project domain i just typed pr in there it took me right to the layer i wanted and the field is called cell size that's your grid element the side of your grid element size okay and then if you have like your elevation data is in a raster you can align it to this raster and i'm going to click ok and it's going to tell me that there's a grid already saved in the database do you want to overwrite it and i click yes now i don't know what my cell size was in that project domain but it might give me like a few too many cells which is okay i think my original or my 10 meter grid size gives me about 44 000 cells and i'm not sure what the cell size is here well it's taken a while so i'm assuming it's three meter cell size that's okay maybe i'll pause it and then when it's done it'll tell us how much time it took okay so uh yes the cell size was three meters and that gave us 494 000 cells and it took one minute and 11 seconds to complete uh now again if you click this button and you try to calculate something and it tells you that there's no computational domain you have that bug that i was talking about so you need an update to the plugin i've already fixed it and i've already merged the code so just get with me and get the bug fix or just put your project domain copy your project domain to the computational domain layer like we used to do before i had this alternate system now we're finished with this guy uh let's see what do we got here where is this dude zoom to layer weird uh oh god good grief sometimes i wonder about my brain okay move those to the bottom we don't want those to be covered up all right so now let's go ahead and zoom in and you can see these are 1 meter by 1 meter grids and you can see we have let me grab this id tool right here and if i click on any one of these you can see that we now have 494 thousand cells now let's grab this new interpolation method and it is this guy right here there's actually two new interpolation buttons but i'm only going to show you this one and it is interpolation from lidar files now the first thing it's going to have to do is uh create the rows and cells of the data so i'm going to click ok and let it start doing that now it is calculating the rows and cells of the data so that it can set up a numpy interpolator and interpolate the points by a point by a just a standard average it's not a distance weighted average now the rows and numbers were already assigned and so now it opens up so that you can select all of the files that need to be written to code now this is important if your data is on your c drive and your project is on your d drive this process is just going to take forever so make sure all of your data your geo package your qgz everything is on your c drive before you do this i'm going to click open and it's going to start now you can see that it's reading the data right here and now it's updating the elevations so the interpolation is basically done and the kind of the thing that takes a long time is like getting the data back into the geo package and um so this is going to take about a minute or two but i'm going to pause the video and we'll come back because it'll give us it should tell us how much time it took once it's finished okay so this is still processing so while it's processing since i'm not sure how long it's going to take let's do one more thing and i will minimize qgis we're done with this and now let's talk about converting the data between um laz utm to laz or to state plane okay so let me grab this now i'll do this one from the laz gui because i my qgis is being utilized by something else and i don't wanna um i can't it's locked down but like that i could open another qgis and do it that way but you've already seen the process through laz so let's take a look at this one through the laz executable so this one to convert the units you want to do last to last and just open this up all the way because you're going to need everything in here let's see what we get here so we need to start by adding the data and if i do this and so be careful the first couple of times you use this it might be kind of annoying because um it doesn't like the the browsers and things like that are not that great so c colon backslash projects c and i click go and then that takes me to my c drive my project folder for my c drive and here's my um project and here's my last yeah it's kind of like the raz one you know it kind of sucks navigating to things like i don't know why they can't just give you a little open button so you can go navigate using windows and then it just fills it but they didn't now we're going to use these for here so let's just click add and it will add all of these and there you go you can see that we have them all right there and i want to make sure and delete the ones in here because i want to overwrite them and i'll move that back out of the way and then we will let's see [Music] we don't need to filter anything because i can just not worry so much about the filter okay but i do need to set the projection so my projection i know is utm i know it's zone 15 and it's the northern hemisphere the datum is nad 83 i don't let's see now at 83 that's this guy right here oh and let me show you how i get all this information i mean you probably saw this already when i loaded that tiles shape file but i forgot to show you this other stuff on here so if you don't know the metadata of your project you can come here and you can click metadata and it will give you the quality information spatial reference that's kind of all i use out of here so the data quality talks about how the data was how they did the quality control on the data and it gives you the vertical accuracy which is plus or minus 18 centimeters and it gives you the horizontal accuracy which is one meter it also gives you the spatial reference info and so our horizontal coordinate system is utm zone 15 north and our um let's see do we need anything else out of here and our horizontal datum is nad 83 and our vertical datum is nad uh sorry navd 88 and the units of both are meters so that's what we need for our conversion program we are not going to convert a vertical datum we are just going to convert the horizontal datum and we are going to convert from units of meters to feet okay so we got our utm zone 15 northern hemisphere not 83 elevation is meters vertical datum is navd 88 i don't i think the g o id was i don't know if that's the vertical go id it didn't really say so i was just leaving that blank um the horizontal uh geo id was 80 but i didn't see one for this one so i'm just going to leave that blank and it seems like it's fine it seems like it's working fine [Music] and i don't need any of this other stuff keep this thing as simple as you can output data okay now for the output data we need to change the directory so again this is like the worst part of this but it's okay it doesn't once you get used to it it's fine c colon backslash projects c and then you hit change and then you can grab that and we are going to pop that into this folder hopefully this will work and click use current and then if you put your cursor in here you can see that everything that that path is cool and then target projection is state plane iowa so just don't bother with your cursor it doesn't work just try to find the eyes let's see or maybe it does work let's see i oh yeah it does nice somebody took me to stupid idaho instead of iowa i need ia yeah i don't know why but it does not like to go to iowa right away oh shoot that's funny uh illinois indiana iowa here we go iowa north and um okay northern hemisphere the unit we want this unit to be feet and we want the elevation to be feet and i don't know what to do with precision so oh i know what it is it gives you like that so i'm just going to leave that default and see what it gives us and then the output format is las and we're going to run this in 64-bit so this is the key don't hit quit or don't hit close on any of these buttons because it'll close the whole program you gotta start over um so do hit run 64 and cool thing is here is that you can you can see that it's all here so again i'm going to copy that and now this is the to last so once i copy that i can go back here and i can grab this dude last to lazz and i can open that in notepad and paste that in there and kind of doctor it up a bit to make it look correct and then we can next for the next one we'll show you how to use those and then just click start well let me get back here and open our state plane first and click start and then what we should see is this dude should start to fill up um [Music] horizontal datum source unspecified assuming save as target i don't know why it says that but it seems to work so i'm just going to like ignore it now it did not put that in my folder for whatever reason it did not like the fact that i chose yeah this is so annoying it i don't know why but it just this thing just does not work that good i'm gonna try it one more time i think it's in the bin folder right now and if you looked in your bin folder you'd probably see that they're there last two nope they're on the band folder that's good and they are maybe they're here yeah they put them in here instead okay so i'm just going to grab these dudes and i'm going to extract and i'm going to cut them to this state plane folder and let's do this real quick so so i'm done here close this and now i can close this and uh let's check our qgis real quick and see that's still going so let's just let that do its thing it's probably going to take like 20 minutes and then while we're waiting let's go ahead and open a clean qgis and we'll put it to the new coordinate system and then we'll load the data actually we'll probably have to load the data as a text or a dem or something like that so yeah we can do the dem conversion and then load the data so this is the uh lidar project with the state plane coordinates so let's try this guy and i'm gonna just remove these i had messed up this webinar and i had um both my geo packages were on my d drive but my data was on my c drive and so i kind of messed everything up for me okay now now that now let's use so that's why i had that um message to remove the all the layers because otherwise you would see them twice all right let's grab this guy here and let's just guy we're going to do last 2 dem and we are going to fill this in for just one file like we did before okay and let's just grab this one and we don't wow yeah let's do keep class two and the pixel size will just say one one actually maybe should put that to like three since we are and elevation is the attribute actual values and i'm gonna just not worry so much about any of these guys and yes i want to save to file and let's just grab that name dot tiff and click ok and click run now i i don't think this is going to add that tiff to the map it did not but what it did do is it gave us a kml um a tiff file and a world file so we're just going to drag this guy over here and oh my goodness i don't know what this is like why it does oh look i left that at um default and it gave me a bunch of these i'm not sure why this doesn't show up for me i did i had the same problem a few days ago like i put this into the map and you can see the data's there and you can see that there's nothing wrong with it like you can see that it's in the right range and everything and if you hit id and you click on it let's see zoom to layer so if i go right in the middle says no features found i bet you i wonder if it has something to do with the fact that my world file is not being loaded with it like it's not identifying the world file let's try this now if i did it from the gui then it will load okay let's try this maybe it'll recognize the world file i have no idea what this is for i bet you it's lost let's do this let's let's try this ah look no dang it sorry yeah there we go okay yeah that was what it was it didn't it projected it in the right coordinate system but it didn't but i think because i'm not sure what happened but it looks good now and so you can do that for all of your rasters or you can do that as a batch processing and if you did it as batch processing um you would get you could merge them all into one but if you do that the blast is not a free tool so it's not your data is not going to be perfect it's going to have vertical lines going through it so you won't be able to use it to analyze your elevation because it has vertical lines that have a zero elevation in there or maybe even like a negative a negative 999 elevation or something like that so it's no data so you have to purchase the tool in order to get this to process correctly but you can see that it's loading in the right spot so the coordinate conversion worked once we you know assigned to the correct system to it it works just fine now so you can use both of those tools i'm not sure what the kml gives you but i guess oh great excellent okay so that took 15 minutes to process the points there were 1 million points inside the grid and 355 000 outside the grid and it took 15 minutes now i'm going to click ok and i'm going to anything that has a 7 000 points were not interpolated 7000 cells because they were buildings or you know something missing so i'm going to interpolate those from the nearest grid elements and click ok and that shouldn't take very long that usually goes really fast so once that's done then you are going to want to qc your data and cancel and i do not recommend that you qc your data from the grid layer instead i let's see i'm not sure what's going to happen here let's see what happens here no nothing there if you had some negative 999 data and you use this render elevation checkbox it would probably show you that negative 999 data instead we're going to go properties let's make this a i'm going to change this from simple outline to simple fill and we are going to choose a fill color let's see i'm sorry ace we don't want an outline and then we're going to set this to graduated and we will go spectral and set this to elevation and then classify that and then let's see yeah we do have some zero elevations we don't want any zero elevations let's see where they are i'm gonna click apply oh what the crap i have like oh no wait never mind uh let's see let's try this uh oh no let's say this is okay this is the uh this is the metric map the other map when you do this the other map will be state plane and it will be feet so let me put this up to like i wonder what the lowest value is three let's say like 389 and then click apply fascinating let's and let's also invert the color ramp and apply and then let's just see [Music] if we have some values in here that are zeros let's see what we got let's use the flow 2d id tool oops i need to just close that window yeah there's definitely there aren't they aren't zeros but if there's a zero in here we don't want to see that let's do this let's see i want to filter elevation equals zero and click ok and then yeah we do have some okay so yeah there's some zeros in here where it didn't interpolate from the neighbor correctly so or maybe i don't know maybe why i don't know why there would be zeros in here but we should be able to interpolate those or fix those with this uh this tool right here but you shouldn't see those so that's something that we need to fix probably on our end and it looks like there might also be some zeros on the edges here where there might be some missing data because i might have snapped my data wrong i might have put my cursor wrong when i exported my data like i might not have put my x max up high enough i was probably like right in here and i needed to be like right in here so that that's my fault and these things in here might be our our development fault okay okay so but it worked so that was good now let's um let me let's see what was i doing over here okay i'm gonna stop the recording right now and then we'll return next week to show how to use the batch processors

Channel: FLO-2D Software

Views: 1,302

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Id: o6UB3YuZGGM

Length: 67min 18sec (4038 seconds)

Published: Fri Jun 25 2021