Discovering the Mysteries of AutoCAD Raster Design

R.K. MCSWAIN: Welcome, everyone to Autodesk University 2022. And this class you're in is Discovering the Mysteries of AutoCAD Raster Design. My name is R.K McSwain. And switch slides here.

And give you a little info about myself before we jump into it. This is my 19th year as an attendee at AU and my fifth year to do a solo presentation and the eighth year in a row that I've been part of the Drawing From Experience CAD Manager panel class, which is-- it actually happened yesterday, September 28th. And you could check out the recording of that if you missed the class and it's something you're interested in.

My position is currently I'm the-- I'm one of the IT managers and CAD managers for LJA Engineering. We have about 4,500 employee owners and 47 offices across the Southeast US. About half of that 700 or so are Autodesk, AutoCAD, Civil 3D CAD users. So that's part of my job is supporting those folks.

I've been a user of the software since about 1995. At that time at my previous employer, we were using AutoCAD. We moved on to soft desk with AutoCAD Map, and then eventually on to land development desktop. And then around 2009 or so, transitioned into Civil 3D.

So, that's been my Autodesk path. A few odds and ends things through there. And the Raster Design came in probably around 2005 or six or so is when I first was introduced to this program. And if you ever see anything called CAD Overlay, I believe that was the previous iteration of Raster Design.

It was a purchase by Autodesk and really hasn't changed a lot over the years just because it's pretty much complete. There's not a whole lot that they've needed to do to it. So, CAD overlay, Raster Design, that's the iteration there.

I'm also one of the former "Hot Tip Harry's" for Catalyst magazine way back in the day when it was a print magazine. There was an article in each issue where readers would submit tips. And Hot Tip Harry would review those and publish them. And if you can believe it or not, people used to sit down and retype in that code way back in the day. I joined it around 2009 when everything was digital.

And lastly, I am one of the 60 original members of the Autodesk Expert Elite that actually was formed 10 years ago this AU back in 2012. So, enough of that. Let's talk about what you're here for and that is these four learning objectives that you read when you signed up for this class.

Give you another brief info going back to that 2005-ish era up until the present day when I meet somebody talking to my users. And they have an issue that may be Raster Design can solve. A lot of times, I mention it. They've never heard of it. They don't know what it can do.

It's not a real well advertised piece of software at Autodesk. It is included in the AEC collection now. Prior to that, it was a separate purchase and not a lot of people that I talked to had it-- knew what it was. So, that was kind of my incentive for putting together this class.

And some of the things we'll be talking about is how do you spatially insert manage and view images. If you're an AutoCAD user, you probably are saying, well, I know how to insert images, image command. Well, we're going to use some tools and Raster Design that will bring in images that have correlation data with them into the right location in space, so they're not just at some point you pick in the drawing. They're in the right location.

We're also going to talk about editing and cleaning up raster images. Not all raster images are aerials. Sometimes you may get a scan image from either internally or an external source and the scan quality wasn't that great. There's some other things you might want to do with that image. We're going to talk about how you can do some of those things.

And the third learning objective is how to convert raster image to vector objects. And those two learning objectives there are kind of related. If you have a raster image that you need to make a drawing out of a production drawing, you have to come to some point where you're either going to use the raster image or you're going to convert it to vector, because you want to do other things with that data. And so we'll talk about leaving everything as a raster or converting everything or at least some things over to vector objects, so you can use regular traditional AutoCAD commands with them.

And then the last learning objective is about a tool called Raster Entity Manipulation. That's going to allow you to work on that image as a raster but using some regular AutoCAD commands to do so. It's actually pretty cool little piece of the software.

And with that, I'll switch right over to CAD. And I'm going to be using AutoCAD 2023 and Raster Design 2023. I want to mention that I'm not-- there's been no customization made to either. This is straight right out of the box. And as I was preparing that statement, it got me to thinking that-- that may not make sense to some people.

What is right out of the box mean? If you can believe it. AutoDesk used to ship a box to your business or home or wherever it was were working. And that's what the software came in either on floppy disk or CD. And that's-- that term has kind of stuck around straight out of the box. It really means you've made no customizations to the software.

And I just want to mention that because if you, if you have to design an AutoCAD, you can jump in and do all of these same things we'll be showing here without fear of anything that had to be changed or anything like that. The only-- one little thing I did a little different was set my QNEW command so that it opens a particular template. That's the only thing, just so we can save a little time.

And you see I clicked the QNEW button, I got a blank drawing here. We're going to jump into this drawing. And the first thing we're going to do, look up at the ribbon, the raster tools ribbon. It usually will be loaded as the rightmost tab in your ribbon tabs.

And generally speaking, not always, but generally speaking, Autodesk does lay out the tools in order left to right that you may use them. In this case, the first thing we need to do before we can work on any raster images get one in the drawing. So, the far most left button is titled Insert. We'll click that. It will load the splash screen the first time you launch.

And we're here in what looks like a normal AutoCAD file dialog. You have the buttons here on the left. You have your listing of files in the middle. But you'll notice there's some other things, there's a little information box over here on the right. And there's some choices down here at the bottom under Insert options and multi-frame options.

The image I'm going to choose is this TIF image. T-I-F is a file extension. And you get a little preview here on the right. It also gives you some information here below. The type of image is tiff. Even though the file extension is TIF, most file extensions are for three letters. Sorry, the actual image type is tiff.

Just another way of spelling it. Tiff images can include multiple images in one file. This is a single image in one file. The color depth is important to note because we're going to be talking about that a little more later. But this one is 32 bits per pixel.

I didn't do the math on this, but I believe that's somewhere in the neighborhood of 30 or 40 million colors per pixel. So, that's just a long way of saying this is a true color drawing. This is a very colored depth drawing. It has a lot of potential for being used, such as an Arial or anything like that.

This happens to be a US GS map. It probably doesn't need to be 32-- 32 bits per pixel. But that's what it is. That's what it's telling us it is.

And it's also 5,400 pixels wide, 6200 pixels high. So, you can do the math and figure out how many pixels are in this drawing. I believe it's somewhere around 35 million.

So, let's look at the options on the bottom. There's Quick Insert, there's Insertion Wizard, Insertion Dialog, Quick Insert, if I click Open, it's just going to throw the image in the best possible way it can. There can be correlation data attached to the image.

There can also be what is called a world file. A world file is nothing more than a [INAUDIBLE] file. If I switch my files of type, I can see there is a TFW file, which goes along with a TIF file. If I were to open that file up, you'll see that it's composed of six lines of text. That's it.

Due to time constraints, I'm not going to get into all the details of this. But a TFW file goes with a TIF-- a-- I believe if your image is a JPG, JPEG, the Word file is JPW and so on and so on. The image itself can also have correlation data in it. It doesn't necessarily need to be an external file.

But if you receive a file from someone, you might get that word file with it. And the other options here, Zoom to image. Yes, I want to have it Zoom to the image. I don't want to show just the frames only, so that's unchecked. And this is not a multi frame or multi image file, so this is grayed out.

So, I'll go through the insertion wizard. That's going to be a dialog that is next, next, next, back, back, back, that type of wizard. You've probably seen that in other places in CAD. So, I'll click OK. And the first dialogue that I see is Pick Correlation Source.

So, where do I want to get the-- the data in order to locate this image from? Inside the image file itself, in the world file, or use defaults. You notice if I check use defaults, the image shows up down here to my left and by the 0, 0 coordinate. Well, I don't want that. I want to use some of the data either in the image or in the World file.

So, I'm going to choose in the image. If you'll notice while I'm clicking through there, the data does not change. It's the same. So, someone has generated the correlation data in the image and they've also provided an identical world file. So, I'll hit Next.

Again, it's a recap of the data in the image. I'll hit Next again. And then, I don't need to change or do anything. I can just hit Finish. And remember, I had chosen to Zoom to the image which it did. It laid the image right in there.

And if you look at the coordinate values down in my status bar, you can see that it's not at 0, 0. It's several-- it's scaled and it's also way far away from 0, 0. So, how do we know this is where we think it is? How did-- well first off, we have to trust the correlation data that was attached to the image.

But let's check by inserting the Bing map images that come with AutoCAD. And it takes a few seconds to get this loaded up. And while that's doing that, I will click up here.

And I have something saved in the history. And again, I'm going through this really quickly because we're-- do have a limited amount of time here so this should be-- if you've used the image the geographic location command in AutoCAD, you should be fairly familiar with this. But I'm just going to go through it really quick.

I know this is TX83 FCF is my zone. I'll click Next. I know the intersection point is right there. And I'll zoom out and hit Enter to allow it to load. It takes a few seconds to pull in that data.

And you may or may not have any idea whether it's in the right place. But if you'll look at some features such as this road and this road. As I pan the drawing, the raster image will disappear. And you can see those roads underneath there they line up pretty close.

So, that is inserting a image that has correlation data attached to it. I'm going to go back to the raster tools and show one more thing. Up here in the Manage and view panel and the ribbon, there's a dropdown that will show you all of the images that are currently loaded in the drawing. The button next to it will open this palette.

And inside this palette, there's a dropdown to let you choose from image insertions which is a list of all the images in the current drawing. And if you drop that down and choose image data, you can draw your way down into data about the image itself. There's nothing here you can really change. But if you wanted to see the xy position, the scale, anything about background transparency, things like that, it's all listed there.

So, I'm going to go ahead and just close this drawing. We don't need it anymore. And we're going to start with another new empty drawing. And one of the things we're going to do here, we're moving on to learning objective number two, is cleaning up and making some edits to images.

Again, insert. I'm going to drop into this directory. And I have a couple of-- three actually, images here with roughly the same name. And I want to show you the difference.

This one here, they're all of the same object, but they've been scanned in different ways. The one in the middle is a TIFF image, single frame, 32 bits per pixel, which is the same as the previous image we were looking at. If I slide the bar over, you can see that it's about 2.3 megabytes in size.

When we're doing editing and cleaning up of images, we cannot work on a full color image such as this. Raster Design is going to complain if we do. And it's just not going to work.

We need what is called a bitonal image. That is an image that has been scanned where every pixel in the image is either black or white, on or off, 1 or 0, however you want to classify it. If I click this other image here, I get a new description it tells me it's also a TIFF image. It's also a single frame.

But look at the color depth now. It's one bit per pixel. So, if you multiply the width times the height, that'll tell you how many pixels there are in this image. Every single one of those can either be black or white. There are no exceptions.

And if you look at the image size, it's only 185k. It's much smaller than that full color version above it. So, we're going to click the Quick Insert because this particular image is a scanned image from probably 20 years ago. It does not contain any correlation data. There is no world file with it.

I just want it to come in. So we can look at it. So, I'll hit Open. And it takes me right to the image. Now, as you can see here, if you look at the coordinates down here as I'm moving the cursor around, this entire image is only maybe three feet across. And it looks like maybe two feet tall.

So, kind of looks like a 24 by 36 sheet. But guess what, we're going to want this to full scale at some point. If this-- this is basically scanned in at one to one as-- like I said, 24 by 36. We're going to want to scan this up.

So, for now, let's just take a look and see what we can do with this. If you'll notice, I mentioned earlier that every single pixel in this drawing was either on or off. The white areas are the portion of the scanned image where the scanner picked up objects and made that particular pixel on. And I'll illustrate that by changing my background color real quick to something other than black.

And now you can see that the background is showing through this image. There is no white or black. There is only black. The white or the off pixels, if you will, they don't they're basically transparent in a bitonal image. So, that cyan is really annoying so we'll switch that back.

And let me zoom in here and show you what I mean by these individual pixels. This is probably one individual pixel right here. And there's whatever-- however many million of them there are in this scan. And this is almost a solid-- this is a very dense portion where the scanner picked up some-- probably some-- not sure if the paper was bunched up there or why it has that dark edge on it there.

If we pan over a little bit, we have the same thing on this end. If you look around, this was some text here. And it's just all garbled up. This is the nature of scans.

I will also tell you that the humidity in the room at the time of the scan stretches or shrinks the paper, if the paper gets taken through the scanner faster or slower than it should. This is not to scale. We're not going to get it to scale. That's just the nature of scans.

But for example, if I was handed this file and my manager said I need you to make an exhibit out of this map, I could start working on that. And in this case, the map is here. I don't think I want to convert any of this to vectors. So, I'm going to start working on it as a raster file.

So, I am only concerned about this portion of the map. So, I'm going to go up here and say crop. And you can see there's different types of cropping. I'm going to say rectangular. I'm going to grab the upper most right corner.

And if you're used to the Zoom command, you would expect this to start drawing a rectangle. But it doesn't. The very next prompt is you have to give it an angle that you want this rectangle to be. I'm good with zero. And at that point, you can draw your rectangle around those objects.

And just as easy as that, two or three seconds, we have cropped out everything that we don't want minus a little bit of stuff. I purposely did not use a polygon to define the area because I also want to show you how easy it is to remove these other things. So under the remove menu, you can come over here and choose one of these shapes or line circle arc. There is a polygon, there's circular, there's a rectangle.

For ease, and since it kind of matches the Erase command in AutoCAD, I'll just use a rectangle. And essentially, I can start at this point, erasing pixels out of this drawing. Now, if I stop for a second, and I grab the AutoCAD erase command, what do you think's going to happen? Nothing.

This is not vector line work. This is still part of the raster image. It's similar to if you were in Paint or Photoshop or some other raster editing tool. There are no AutoCAD entities in here, except for this one image.

So we have to use these tools provided, such as remove rectangular region. I'll come up here and remove some more. And I'll just keep speaking to you while I'm browsing around here and removing just to show you how easy it is to do this. You do have to be a little careful. You don't want to remove too much.

Although, there is a way to get it back. Now, you see what I'm doing here. I'm zooming and removing and zooming and removing. And you're probably thinking, wow there's got to be a better way than that, to do all this stuff. Well actually, there is. I'm glad you asked.

There is a tool called Cleanup and Despeckle. And what that's going to let us do is get rid of all these little dots, these little artifacts. Again, when the drawing was scanned, if there was a smudge or a piece of dirt or something on the sheet, the scanner will read that as an object and put the pixels to whatever you want to call it, black or one or on. And that's where all these little dots and things come from.

So, we will use Cleanup, Despeckle. And the first thing this command ask you is which portion of the drawing do you want to work on? Well, let's work on the whole drawing, entire image. And then the next thing I'd ask you is pick a special to set the size or I can define the size by window, size and pixel, size and units.

Well, again, I know this drawing is about 24 by 36. But I have no clue what size some of these are. So, I'm just going to pick one of these and see what happens. So, I pick right on it and instantly, probably-- I would say dozens, maybe hundreds of them or so turn red. That is to let you know that is what it's going to erase when I hit the Enter key.

But if we look around, you can see, there are several that did not pick up. So maybe, if we look at down here on the command line, it told us that the pixel I chose had a size of five. So, what if we re specify the size, size and pixels, and let's choose nine. Let's get a little larger.

We wanted to get more of those dots out of our way. Well, it still missed one here. But more importantly, look what it's doing to some of our text. It's taking off the foot sign, the inch sign-- I'm sorry, that's minutes or seconds. In this case, over here it's a foot sign. Over here there are periods, there's commas. Probably not what you want to do.

And just as a reminder, this is not text. It may look like text but it's also pixels part of this drawing. So, let's cancel that. And let's do something a little different. Let's do Despeckle.

And this time, I will use the Polygon. And I'll come through here and I'll try to ignore some of this text so that we're not grabbing it. And I'm not going to spend a whole lot of time doing this.

But just to show you, you can work on a portion of the drawing. And we know our size and pixels now. It's got to be larger than five, smaller than nine. Let's go with seven. And see, that looks pretty good. That's getting rid of a lot of those areas.

So a hit Enter. The boundary I just created is gone, and most of those areas are gone. And again, while I'm sitting here speaking to you I can literally go through them this quick to get rid of a lot of this stuff. I could probably manually clean up this drawing in 15, 20, maybe even 30 minutes. It doesn't take a tremendous amount of time because these tools are really well thought out and programmed.

Here's some stuff here. I don't know what this is. Maybe some-- maybe there was something else with ink or pencil on it got laid on here and it got scanned in. So, I can easily do that. And oops, I remove some of this line.

How can we get that back? Let's come back to that later. We will come back and fix that.

So, we've got this drawing fairly clean. I know it needs some more cleanup. But in the interest of time, let's pretend we got it where we want it. Now, we know that the distance from this point here-- you can see where my line starts-- down to this point here is less than one.

We're probably going to say that's one foot. So, it's a little over six inches, seven inches. But it's supposed to be 791 feet and .06. So, how can we do that?

Let's do this real quick. I'm going to change my color to something other than white. We're going to draw our first CAD entity in the drawing. It doesn't matter where. I'm just going to pick a point.

And I'm going to use the old school method and say @791.06 angle, north 87 degrees, 54 minutes and 59 seconds east. And if you're looking at the text right above me, you see that it is a Southwest direction and I entered Northeast. I want my line to go to the Northeast not to the Southwest. Those angles are exactly the same. There 180 degrees from each other, so this is going to work.

And you can see that line is roughly the same bearing as what's on the screen, but it extends way out to here because that's our true length. So, how do we get our drawing to match that? If you're a seasoned AutoCAD user, you might say, I'll use the Align command. Well, there's something similar inside of Raster Design we can use. It's called Match.

And what we'll do is we'll roughly eyeball this point. I don't need to be super exact because remember this scan is not even-- is not exact itself. So, I'm going to grab that point to that point. And then my second point will be here. And we want it to be at the end of this line way out of here.

Still zooming, pick the endpoint. As soon as I do, hit Enter. Drawing should be there. You can still see the magenta line under there. Now, it matches this 791.06 feet in the drawing. I'll get rid of that magenta line.

And just to test and see how close we were, let's make a couple of measurements up here from this point to this point is 77.24. It's supposed to be 77.71. It's pretty close. And this one, 198.38. It actually measures 201.06.

So, fairly close. But again, even if you took a scale and printed this out and measured it, none of the-- might get one dimension right but they're not all going to be right. Just the nature of paper to digital scans certainly 20 years ago.

So, we're almost ready to-- we're almost ready to complete this exhibit. Only thing we need is my manager said I needed some aerial imagery in the background. So, let's go back to the geo command once more.

And in this case, I have some-- a Lat long that I know is in this vicinity. And if I Zoom in here, I can tell you since I've done this a couple of times, the center of this cul-de-sac or I should say this cul-de-sac matches the one here on the screen. So, I'm going to drop my marker right about the center.

I'm going to hit Next. It's going to load up all the coordinate zones again because it didn't remember doing it last time. This time, I'm at TX83-SCF, South Central feet. I'll hit Next. It asks me where is that point in this drawing. About right there.

And another two, three, four seconds here and there's my aerial image in the background. Now, if you're looking very closely at what we're doing here, yes, this line does not match this fence line. And there are houses going down the middle of some of these lot lines.

I do not know the history of this raster image map. I don't know if it was finalized ever constructed in the field like that. But for what we're doing here, it does illustrate that we can get pretty close. I don't even know if this raster image has been manipulated before I got a hold of it.

So, we're pretty close. We've got this reserve over here where the sewer treatment plan is. We've got our easement going down this drainage ditch. And you can see that in about-- I don't know, 15 minutes or so, it probably hasn't even been that long. We've generated a fairly decent exhibit by getting rid of pixels that we didn't want, keeping the ones we did, dropping an aerial image in, and there you have it.

Let's move on and talk about converting some of this register to vectors. Again, I'm just going to exit this drawing. And what is this? This is a new dialogue.

You-- if you were paying close attention, I just told AutoCAD I did not want to save the drawing file. But now, it's also asking me, do I want to save the image? This is something that is pretty unique to Raster Design.

It knows I've made changes to this image. Do I want to save them? Well, I don't because I may want to do this again. So, I'll just hit skip that time.

So, if you see that, that's what it's asking you to do. There is an option inside of Raster Design to allow you to save the image every time you save the drawing. I do-- I do not have that checked. And I didn't save the drawing anyway. That's why it's asking me, did I want to save that.

So again, starting another new drawing. This time, I have a already cleaned up version of that same map. I'm going to do a Quick Insert. I don't really care about the scale or anything at this point. This is more about going over some procedures to convert some of this to vector lines.

And when I say vector lines, that would be anything that you would normally draw in AutoCAD such as a Line, Art, Circle, text, things like that. Again, if I use Q Select on this drawing, there is absolutely nothing in here except one raster image. That's it.

So, we can come up here to our menu again. And there's a vectorized and recognized text section. And in the interest of time again, I'm not going to change any of these options. I will show you that if you click-- let me exit that again. If you click the down right arrow which is at the bottom right of-- let's see, one, two, three, four of these panels-- it will open the options to that particular tab that corres-- I have not changed any of the options in here that are straight out of the box, to use that expression again. But just to show you that there are things you can come in here and change.

We're going to use this just like it is. And I'm going to start with the primitive section under vector eyes and recognize text panel. And I'll start with a line. And what this is going to do is allow me to select this raster line. And it's going to convert it to a vector.

Now, how does it do that with these gaps in the way? It has some intelligence built in. But it's not super intelligent if that makes sense. There are limits. There are settings in here. You can tell it to ignore a gap of so many pixels or so many drawing units.

I'm going to also check on the raster snap toggle up here in the upper right. And the two snaps I'm going to tell it to use are the center of raster line or the end of a raster line. Now, this was interesting when I first used this because how does it know where the end of that raster line is?

You can look at the cursor and see that it looks a little different now. It has a large square attached to it. So if I wanted to draw a line myself, I'm not going to convert anything. I just want to draw a line from the end of this raster.

And you can see-- hopefully, you can see the little circle with the x in it. It moves and moves. And it gets to right there and that's it. And that is the end point of that raster line. It's not going to let me connect to this very tip, this tip, this tip. It's going to connect right there where the crosshairs are.

And that is-- it's making a judgment call as to where the end of the pen or pencil that drew this line would have been at the moment they stop drawing. So again, if I wanted to draw a line from the endpoint of there-- well, I got to get a little closer I guess. I think I got it confused.

Let's move on to the primitive section. Here, we're actually going to convert some of this raster to line work. And we'll start by zooming in a little bit and selecting this line. And hopefully, the yellow highlight comes across on the recording and shows you that picked up this entire line from end-- start to end.

On this one, it did not. And I believe the reason is the gap between here and here is larger than any of these other gaps and it just didn't work. So, I'm just going to leave that one alone. And you'll notice when I pan the drawing, the raster disappears and you can see the vector line work underneath. This one worked.

This one did not again. Leave it. We'll just move our way around. And as you can see for the most part, it's converting this line work pretty well. That one missed again.

That one worked. That one worked. What about this one over here? Nope, that missed again. That one worked. And that one work for the most part.

There is another option here. I can come down to the command line and pick 2p for example. And maybe I can pick there and pick-- my second pick or even my first. One of the two doesn't necessarily have to be on top of the raster image. And I drew that extended because I'm also going to do a 2p on this line.

And let's say I started there. And I come out here, and you can see how I can extend that beyond. And now, when I want to finish this off, I can just use a fillet or trim to get both of those as opposed to trying to draw them to short and connect them up later. So as you can see, I'm panning. I'm getting this drawing converted for the most part.

And I may want to use the 2p again. I'm not going to do this entire drawing. But I want to give you a little bit of a sample as to how it works. As you can see, that one did not progress.

This one is not-- this line work here for whatever reason is not wanting to generate down, ended up with a bunch of little segments. So, probably don't want that. So in this case, I could start at that point.

And I know you may be thinking, hey, how come you're just fudging this in here? Again, this drawing is never going to be what you want it to unless you start with something known, such as maybe the center line of this road and the center line of this road and start doing offsets and things like that.

The raster imagery, the pixels in this drawing are just not that accurate. And they probably won't be unless you have a really recent scan of something that is scanned to a super high DPI meaning dots per inch. So, as you can see, we're able to convert some of this line work to-- I'm sorry, some of the raster imagery to the lines.

But what about the arcs and the circles? There is also a primitive arc setting. And in my experience, this takes a little bit of looking around here. And there it is. It finally picked it up.

And it's a little hard to tell. But this road coming into this cul-de-sac is also on a curve. It's just a very slight curve. So, I can use the 3-point option of the arc. And I can pick here, here, and approximately here. And I'll repeat the process over here.

I missed the 3p so let's redo that one. And then, going back to my remove. And then I can just use regular fill-it command with a radius of, say, 25. If the extra pieces of the AutoCAD cursor are bothering you, that's the raster snap. We don't need it on.

And again, because we were converting raster to vector, you're going to have places like this that you'll have to clean up. You're going to have places like this that you'll have to clean up. So, can you just trace on top of it? Sure, you could do that.

The next example I will show you is going to illustrate why the vector rise tools are much more valuable than just say tracing on top of this. Because that's essentially what we were doing by doing the multiple pick on the line, multiple pick on this arc, was kind of tracing. But let's put this aside for a moment [AUDIO OUT] a new drawing.

Insert another image. This one is the image of a contour map. And as you can see it, it also has some scan residue out here. You might call it a few little pieces out here. The easiest way to get rid of all of that is to use crop. And this time, we will do a polygon, go around, and it's all gone.

Now, if you're not in the civil world, this may not make a whole lot of sense to you. But you can see the elevations on these contour lines. This one here that my cursor is on top of is 504. The one up here you can clearly see is labeled 514.

So, between this point and this point, the elevation changes 10 feet, which may be say the height of the ceiling in your office building. But if you look, I just did a distance command, and vertically-- I'm sorry, horizontally on the ground, it changed 0.03 feet.

Well, that is totally ridiculous and out of whack, because there's no way that would be a vertical wall essentially. And it just doesn't make sense. Again, I don't know the source of this drawing. I don't know who scanned it, where it came from. There is no correlation data.

But that is certainly not right. There's no way this is 4 inches and yet it raises 10 feet in height. So, for the purpose of this illustration, I'm going to take this image and scan it-- I'm sorry, scale it up 200 times. And the reason I don't want to scan the final vectors is because if I convert these contours to vectors and then scale them, the scale will affect the Z elevation or the height of the contours.

So, I want to get my raster drawing scaled up to the right scale. And we use 200 just as a kind of guess you're going to want to know what that scale factor is. If it was a 1 inch equals 200 feet drawing and it was scaled 1 to 1, that 200 would fit perfectly.

So now, we can go up here to the vectorized panel under followers and we'll choose contour follower. Again, there are options for this. Time doesn't allow me to go in there and show you all those options. But I think it's kind of neat just to drop right in here.

This is again, straight out of the box. We're just going to use it and see what happens. We're going to turn our raster snap on again. This is 502. We'll follow it back to here.

And if you can see the blue highlighting, it found that entire contour. And I'm going to hit Enter and choose 502 for the elevation. I'm still in the command.

The next one would be 504. That would be this one right here. And let's see what it did. Oh, it stopped right here. And my cursor is attached to the wrong end.

So, to change that, I have to click Switch on the command line that attaches my cursor to this end. And you see what happened here. It was following it. Remember our menu item is followers. So, it's following this raster.

And then it got to this point, it didn't know what to do. It didn't to double back and do this. So, we can click rollback. I can click back to this vertex. And then I can just start clicking myself on here, my raster snap is on.

And then when I get to a point where I think we've cleared it out, I can hit Continue. And it takes us all the way to the other side. And my elevation of that one was 504. And we'll do a couple more of these. 506 is next.

And look what happened, it stopped again. It stopped here because the pixels that form the zero are touching the pixels that form the contour line. So, here I can go back up, and simply pick another point out here where it should go and then click Continue. It takes us on around, finishes that one.

That one was 506, I believe. And we'll do one more at 508, which is this one. They grabbed the whole line. There's no problems there.

And then when we get done, now, we have some vector line work in the drawing. These are polylines now. We can go into properties and change, say, the color so they'll stand out. And you can see how they differentiate from the rest of line work.

And if I drop into a 3D view, you can see that they are in 3D. It actually assign those elevations and you can take this and drop it into Civil 3D or any other application that can use them. And in the interest of time, I won't convert all of those. But I do have a drawing that has been fully converted just to show you what the entire thing looks like.

So that is converting raster imagery to vectors. In this case, they were contour lines. And the last thing regarding raster to vector would be converting text. And if you're familiar with copy machines, small format, maybe you've scanned some documents into Adobe or another applications such as that and you've changed the scan text into editable text. It's a technique called OCR, Optical Character Recognition.