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Please be patient when loading this page, some of the images are quite large. |
| The word Vectorization is not defined in any dictionary. So, what is it? |
| Our Scanning FAQ provides a very good explanation of a raster image. Vectorization is the process of changing the raster lines, arcs, circles, text and other raster information on the drawing into vector information that can be understood and used by a CAD system. Once in the CAD system, the software can then manipulate the vectors - move, scale, rotate, copy, etc.. CAD vectors are defined mathematical entities. That is to say, a line has amplitude, direction, and a finite place in space. Raster, on the other hand, is simply a picture made up of black and white dots. |
 "Portion of A Typical Raster Scan" |
 "Vector Conversion by CGA" |
| How is this vectorization accomplished? |
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There are several ways to convert raster data to vector entities: Automatically, Line Following, Heads up Digitizing, and the way CGA does it. Below is a brief explanation of each method.
Before we talk about the different vectorization methods, you must understand something about drawings. They are not perfect! That really hurts those of us that have spent hours bent over a drawing board, but the fact is, they are not perfect – no line on a manually drafted drawing is exactly parallel or perpendicular to any other line. When we "read" a drawing, our minds filter the information, rationalize the data and make sense of what the drawing represents. Computers and software can't do this, at least not yet. Automatic Conversion and Line Following software does not make assumptions based on the content of a drawing. These programs try to follow the centerline of the raster image. What this means is that even the programs that make an attempt to place lines at 0 and 90 degrees are really guessing where the line is supposed to be. This can cause the resulting vector file to be more inaccurate than the original. |
| Automatic Vectorization – The "magic black box" that was supposed to revolutionize the industry. During the late 70s and throughout the 80s, it was everybody's dream to automatically read a raster scan and create a CAD file that matched perfectly. To some extent, this is possible. Many software programs are available that will do just that – create a vector file from a raster picture. Most of the time what you end up with is a vector "picture" that requires a considerable amount of cleanup. Most entities created are linestrings (polylines for you Autocad folks). Attempts are made to "recognize" arcs, circles, and even OCR text. Some of these programs divide the elements by the thickness of the raster image – thick lines go on one level, thin ones go on another. In the end, you still end up with a "picture". |
"Same Portion Of The Raster Scan Above That Has Been Automatically Vectorized By One Of The Leading Software Products" |
 "Enlarged Portion of Automatic Vectorization" |
| Line Following – This is a slightly different method of automatic vectorization – you get to watch what the software is doing. You are allowed to do the thinking the software cannot do. You get to set up levels, weights and colors and also direct which way the line goes when it comes to an intersection (something you can't do with the "fully automatic" software – it goes where it wants to). Line following software was introduced when users' started to figure out the automatic way wasn't working. Even with Line Following you still end up with a "picture" because many of the same algorithms used in the automatic software are still used to follow the raster image. Most of these programs will allow the operator to re-key text. This re-keyed text is usually placed automatically by the software at a size that matches the raster image. When the operator has "finished" a conversion, every piece of text is probably a different size. This is going to take a lot of cleanup time on your part. |
| Heads Up Digitizing – This is just about as accurate as the old method of board digitizing the drawing. You do get real text, spelled right if the operator can type. You also get things divided out on different levels – if the operator understands enough to read the drawing and tell what the items are and what level they go on. One company has even tried using a video camera mounted on a plotter to place the image on the screen, they claimed that scans were inaccurate. The main benefit with Heads Up Digitizing is the raster image can be displayed and zoomed on the screen to provide more accuracy than board digitizing. This method is also slightly faster. Depending on the operator, this method can provide somewhat acceptable results, but is costly in terms of operator salaries and time. |
| The CGA Way - We approach Vector Conversion from a slightly different perspective. We use methods and software that we have developed over the past 18 years to make our product an exact match to your specifications. Drawings are converted to your level, weight, color and font specifications. We convert your drawings based on the intent of the drawing - we don't draw pictures!
Scans are warped to "real world size" before beginning the vectorization process. Dimensional accuracy is used in the warping process to establish the "real world size" so the completed drawing is, in many cases, more accurate than the original. For the most part, dimensions on the drawing are used in our conversion process. If a wall on the left side is dimensioned 12", then all walls on the drawing that are dimensioned or drawn as 12" will be 12". Lines that are supposed to be parallel are parallel; lines that are supposed to be perpendicular are perpendicular. We do not provide complete dimension reconciliation for our standard Vector Conversion work. Dimension reconciliation can be accomplished at additional cost. We guarantee a 100% match of your original drawing AND your specifications – we'll even correct spelling errors we find on the drawings. When you receive your files, you will not need to spend any additional time doing cleanup work because there is none. Just open the drawings in your CAD software and begin your work. For additional information, click the link below. It will open a new window which you can simply close to return to this page. Additional Information on Vectorization |
| How much can I expect to spend to convert a drawing or group of drawings? |
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This question cannot be answered directly. CGA does not quote prices for conversion work without first seeing a cross-section of the originals. Quoting a fixed price for conversion services up front means that the vendor will perform that amount of work and the rest will be left for you. Automatic vectorization is normally priced in the $50-$75 range. You get exactly what you pay for. CGA does not sell Automatic Vectorization services.
For drawings converted by Automatic methods and costing in the $75 range: Expect to spend 12-18 hours of your time trying to make the drawing fit your needs and expectations. If you decide to purchase the conversion software, expect $2,500 to $5,000 in direct cost. Don't forget to add in the time to learn the product and the testing that will be required to get the "best" results. For drawings converted using the Line Following Methods: Expect to pay $1,500 to $3,000 for the software, 4 to 6 hours of operator time to watch the software trace the raster on screen and an additional 6 to 8 hours for cleaning up the drawing. If you choose to employ the Heads Up Digitizing method, you can expect to spend from $1,800 to $2,500 on raster manipulation software for editing and working with the raster scans. Don't forget to add in the time and cost for an operator to trace the image on screen. Depending on the drawing, the operator's time can be very extensive. When you choose to use ComputerGraphics / Atlanta, expect 10 minutes of your time to package the documents and prepare a label for shipping. The total conversion price quoted will be approximately 75% of the cost of doing the work in-house. There will be no additional costs involved after the files are returned to you. Load the files on your system and start to work on your project. While we are doing the document conversion, your operators can be doing the work they were hired for – not trying to trace something on the screen or clean up poor conversions. |
| How long will it take to do my conversion work? |
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Once again, this question cannot be specifically answered here. Every project is different. We will provide a budget estimate based on the number of documents you send to us for review. We will also provide a turnaround estimate at that time. Once we receive the full project, we will provide a guaranteed firm conversion price and turnaround time. In almost all cases, your final costs will be lower than the original budget estimate.
We are sure that our conversion services will be faster and less costly than in-house conversion. |
Select the ones you would like to download for review and click the right mouse button over the thumbnail, then select "Save Link As...." and give the file a name of your choice. | |
Automatic Vectorization Example
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CGA Conversion Example
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Automatic Vectorization Example
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CGA Conversion Example
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TIFF Format - G4 Compression
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CIT Format
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