R2V – The Nuts and Bolts of Converting to CAD
What do you do when you have a JPEG, BMP, TIFF, IMG, GEM, CIT, or GIF file that you need to bring into AutoCAD or some other CAD file? The above-referenced files are “raster” type files, while all CAD programs work with “Vector” files. Vector files come in various formats, with some of the most common file extensions being EPS, PDF (which can contain raster and vector) and DXF.
A raster file can also be called a bitmap file and is based on pixel data. When you are viewing the raster file at a low percentage size, the image blends and looks normal. When you zoom in or make the image larger, however, the small squares of data, called pixels, become apparent.
Vector files are based on mathematics and curves rather than pixels. This means that as the image is re-sized, the computer redefines the shape’s pixels so that the image remains crisp and clean. This allows vector files to be scaled based on their intended use, allowing a single file to be used for both a business card and a billboard. The ability to scale vector graphics significantly reduces the amount of time that a designer needs to produce different sizes of a CAD drawing or a graphic, as well as reducing the amount of space necessary to save multiple versions of the same graphics file
What is R2V?
R2V is an acronym for Raster to Vector. Raster to vector is a process by which scanned engineering, construction, or technical drawings are converted to CAD files. The R2V process can also be used for converting maps and other types of artwork that have been scanned.
A raster drawing is considered a computer graphic, regardless of the subject of the file. It may be an engineering blueprint or a photograph of a vase of flowers. Often the file format is a tiff file. R2V simply refers to the process of converting the raster graphics into vector graphics.
In computer-aided design (CAD) drawings (blueprints etc.) are scanned, vectorized and written as CAD files in an R2V process called paper-to-CAD conversion or drawing conversion.
In geographic information systems (GIS) satellite or aerial photographs are vectorized via an R2V process to create maps.
In graphic design and photography, graphics can be vectorized for easier usage and be resizing.
Best Way of Going from R2V
The R2V process is not standardized, meaning that there is no a single correct method, no “one size fits all” from blueprints to photographs. Even within the same category, blueprints, for instance, there are many different R2V algorithms that can be used and each gives different results. It’s important to recognize that vector representations of graphics can be more abstract than raster representations.
Whether you use an outsource R2V service firm, or whether you attempt the R2V conversion yourself, a clean raster image that has been scanned at the correct resolution will improve the R2V outcome. Cleaning means de-speckling, getting rid of unwanted artifacts, smoothing and fixing lines and removing any holes. This can be a time-consuming process. One of the advantages of using an outsourced service is that, in addition to the performing the actual R2V conversion, they will also ensure that the drawing is scanned at the correct resolution and that it is clean and ready for R2V. In this respect, an outsource service can save you considerable time.
While there are software packages that do provide automatic R2V conversion, it’s important to realize that even the best automatic R2V software, requires some human intervention in order to ensure an accurate CAD drawing. This is another reason for using an experienced R2V outsource firm. An experienced R2V conversion service company will be familiar with the “tricks of the trade” used to convert to AutoCAD; Revit; Navisworks; MicroStation; VectorWorks; SolidWorks; CATIA; ArcInfo and other common CAD programs. Often, they will have specialized programs that make the process more accurate.
Finally, a reliable CAD Conversion firm also employs quality control methods for all their conversion projects, from R2V to 2D to 3D. Quality control in CAD Conversion activities requires specified control, intelligent job management, defined processes, reliable performance, and integrity of data and records maintenance. Specific controls need to be in place, including reviews of each converted file by a peer or superior who was not involved in the original conversion process, as well as customer review and feedback to ensure that the customer’s standards are met.