Expert Raster Editing - Reusing and Updating Your Existing Paper Documents

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1 11/28/2005-1:00 pm - 2:30 pm Room:N. Hemispheres (Salon E1) (Dolphin) Walt Disney World Swan and Dolphin Resort Orlando, Florida Expert Raster Editing - Reusing and Updating Your Existing Paper Documents Felicia Provencal - K-Tek Solutions, LLC GD13-3 What can you do with that heap of existing paper documents? This class will show you how to edit these documents with the tools in Autodesk Raster Design. In this lab, you will have a chance to clean up scanned drawings using the editing filters, improve their appearance, and edit portions of the images with Raster Entity Manipulation (REM). With these tools, you will never waste time or designs again! About the Speaker: Felicia is an independent consultant based in Maui. She has over 18 years of experience with Autodesk products in the civil engineering, GIS, and construction industries throughout the U.S. and the Pacific Basin. A popular Autodesk University presenter, Felicia is also a certified Buzzsaw instructor.

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3 Expert Raster Editing In this class, we will look at three different ways you can edit an image: using editing tools to clean up an image, using the image processing tools to improve an image s appearance, and the using the Raster Entity Manipulation tools to change parts of an image. First, let s take a look at the image cleanup tools. Image Cleanup Image cleanup tools can be used to remove defects in the image caused by the scanning process, or by poor original files. There are a number of cleanup tools found on the image pull-down menu. Most of these tools only work on black and white, or bitonal, images and provide a number of command line options to refine how the tools work. One of the newest tools on this menu is the Touchup command. This toolbar provides options that allow you to draw in a raster mode. It is similar to drawing tools in other raster editing programs. You can use these tools to add information to a raster image in a free-hand mode. Processing an Image In addition to cleaning up an image, you can make edits using image processing tools. There are tools for each type of image, and most of these tools allow you to edit the entire image, or portions of the image. The most common edit made to a true-color image is to adjust the contrast, brightness, and color balance. Go to the Image pull-down menu, then pick the Image Processing sub-menu, and then pick the Histogram command. A histogram is a graph showing the distribution of pixels in an image across the color map. The range of shades depends on the image type selected. The darker shades are shown on the left, and the lighter shades on the right of the graph. This Histogram command allows you to edit this distribution to change an image. 2

4 Insert Class Title as per Title Page You can use the various tabs to adjust different elements of the image. If there are several images tiled together, all images can be adjusted at one time by selecting all of the appropriate images. A new option is the Tonal Adjustment tab. This is used to perform non-linear adjustments to the histogram. If you are working with grayscale images, you can use the Convolve tool to adjust the masking in the image. 3

5 Expert Raster Editing For black and white images, there are the bitonal filters, used to thicken or thin out the raster linework. The Palette Manager is a tool that allows you to edit the color palette for 8-bit color or grayscale images. Use the Palette Manager to combine, change, and set transparency for individual colors within the palette. Palettes can also be exported and imported for color matching and web-safe images. If you are working with 8-bit grayscale images, you can use the Palette Manager to add spot color to the image. Raster Entity Manipulation Once the image has been adjusted properly, you may need to edit it to remove portions of the image, or move, copy, or rotate image elements. These can be done using the Raster Entity Manipulation tools. Before you can make the edit, you must select a portion of the image. There are three ways to select the portion of the image to edit: by region, by enhanced bitonal region, or by primitive. A region can be used to select any window, polygon, or other shape of any type of image. These regions can then be moved, copied, rotated, or stretched like any AutoCAD entity. 4

6 Insert Class Title as per Title Page An enhanced bitonal region can only be used with binary (or bitonal) images. These regions can be selected using window or crossing areas similar to AutoCAD object selection methods. A primitive can only be created for binary images as well. These are used to select raster linework such as lines, arcs, and circles by picking the linework to change with a single click. You can also use tools from the pull-down menu to change your raster entity selection. Once the information has been selected, you can change it using any standard AutoCAD editing command (such as move or rotate). In addition, there are several changes you can make that are unique to Raster Design. Once the changes have been made, you should save the changes back to the original image file. Go to the Image pull-down menu, choose Raster Entity Manipulation, then Merge To Raster Image. Alternatively, you can save the changed bits of raster image to separate files (similar to cropping an image). 5