Autotek autocad raster design 2010 Benutzerhandbuch

Apply

Equalizes the image and creates a new histogram that reflects the changes.

RGB

Specifies the color image. You can select the Red, Green, or Blue channel,
or the combined RGB channel. For a grayscale image, you can only select
the RGB channel.

Preview

Displays a preview of the image showing the modifications.
Click an image name to view the preview for that image. Histogram changes
apply to all images you have selected, not just to the image that is currently
previewed.
This preview does not show any display-only adjustments you may have
made to the image using the AutoCAD IMAGEADJUST command. If you
apply changes to the image using the Histogram command, then all
display-only adjustments are reset to the defaults.

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Use this tab to convert a grayscale or color image to a simpler black and white
bitonal image. This operation can be used to isolate features in an image. For
example, you can isolate the contour lines from a grayscale scan of a USGS
map.

After the grayscale or color image is converted to a bitonal image, you can use
the vectorization tools to convert the raster objects to vectors.

Threshold

Displays which pixels are black and which pixels are white. After you move
the slider, all pixels to the left of the slider become black and all pixels to
the right of the slider become white.

Apply

Converts the selected grayscale or color image to a black and white bitonal
image.

Preview

Displays a preview of the image showing the modifications.

320 | Appendix B   Raster Design Dialog Boxes