For this course, we are using a vectorizing software program called R2V. After importing an image, you may select between two methods, Autotrace and Autovectorize, to translate the raster image to a vector image.

The first method called Autotrace allows you to point to a line and select it and the program will automatically draw small connecting vector segments that trace that contour until the line ends in empty space or at a confusing intersection of lines. This method is best for editing coverages as you work because you are only dealing with one line at a time and can add/delete individual nodes as needed, and thus you the user have more input into the vectorization process.

The second method uses the Autovectorize mode. This mode will vectorize all of the lines simultaneously. You must choose between the Centerline and Border tracing options. For polygon coverages (i.e. a political map of the United States), you would use Border mode, which traces both the inside and outside of each raster line to create adjacent polygons with juxtaposed, not shared borderlines. For line coverages, such as topological maps, you would select Centerline mode. This method vectorizes along the center of the raster lines, tracing each line singly.

Editing

To edit your vectorized coverage (removing/adding/moving nodes and cropping), you can use the edit features that are part of the R2V software or export the image to ArcEdit (The editing portion of ArcInfo’s software package).  Go to Editing exercise

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