Ricoh SAVIN A741, Руководство пользователя

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Print Server Manual 35 A741
8.9 What is vectorising?
Vectorising is the opposite of rasterising. Vectorising is typically an action done
after a scan. Scanning will result in a raster (bitmap) image, in fact a collection of
individual black and white dots (pixels). A vectorising program will analyze this
image and convert this image back to individual lines -or vectors-. Hence the
name vectorising. (see also 8.7, 11.2)
8.10 Which vectorise programs can you recommend?
AutoCAD version 14 does not have a built-in vectorise option. For AutoCAD rev
13, rev 14 and AutoCAD Lite a vectorise program RxAutoImage Pro LT is
available from Rasterex. For more information on this product please consult the
web page
www.rasterex.co m.
Additional vectorise (ScanVEC®) and bitmap editing programs are available from
ScanGraphics, Inc. recently changed Name to SEDONA Corporation. See web
page
www.sedonacorp.com for more details.
For PostScript solutions you can use Adobe Streamline to vectorise the drawing.
Streamline will produce an Adobe Illustrator vector file. With this latter program
you can easily modify the drawing. For more information see the Adobe web site
at
www.adobe.com . (see also 8.7, 8.9, 11.2)
Note: Streamline has limits to the size of bitmaps it can handle and is therefore
not suitable for large engineering drawings (scans).
8.11 If I want to scale an image which format will give the best results?
Scaling a vector image will always give the best results. A vector file contains
drawing instructions. Each time we re-scale the image, a new high quality output
drawing is generated.
Scaling a raster image is a matter of compromise. If we reduce the image it will
look sharper, but finer details may get lost. If we enlarge the image we simply
make it bigger without creating a better quality image. We tend to think that
enlarged images are low in quality, but that is not true. The individual pixels are
simply enlarged, more clearly showing the quality of the original file. (see also
8.7)
Example:
The image on the left is at it's original size, the image to the right is scaled to
400%, it looks lower in quality, but that's not true. The image is simply 4 x larger.