Trace Line

Trace Line will convert a line in an image into a single CAD polyline. If an image is "current" through the Set Raster Image command, simply run Trace Line and click on a line in the image. In the command line, you will see the Line Length, Angle, and Thickness reported for the new polyline. The command line will also prompt you to change the Angle, Length or Reverse the direction the new polyline if desired. To accept the new line press Enter. To cancel, type C or press Esc.
Different images have different resolutions or quality to them. To account for this, you can adjust the parameters that the program tries to recognizes linework in an image with Edit Raster Options. Here is also where the default Layer for the new polyline is determined.

Prompts

Pick a point for line (Enter to end):
Select a line in the image
Line Length=780.00 Angle=269°32'47" Thickness=5
Enter to accept line or [Angle/Reverse/Length/Cancel]:
Type in the first letter in a word to adjust that element of the new polyline. For example, typing in "A" would allow you to adjust the Angle.

Pulldown Menu Location:
Raster > Trace Line
Keyboard Command:
rasline
Prerequisite:
Set Raster Image