Turning images into a Shapefile?

[AlbanXhema]

So I have a soil map that is currently just an image in my GIS and I want to turn it into a shapefile so that I can manipulate the colors and control each soil category differently. Currently I have just been drawing them in freehand, but this creates a difference between the contours in the soil map and my GIS. It also takes a lot of time. Is there anyway I could at least make sure that the shapefiles I'm making line up exactly with the lines of the contours in the soil map? Again, the soil map is just an image and I need to create a digitized version of it.

[ChadCollins3]

I would ensure that the JPEG file extension is .jpg and not .jpeg, do this using Windows Explorer.

[DarrenWiens2]

As Lisa touches on, your first step is to georeference your raster, if not done already. Then, your task is to turn that raster into something more usable, using ArcScan or manually tracing the lines into a polygon/polyline feature class. I've also used a supervised classification to train the data into usable classes (i.e. draw training polygons for a few known classes, then run the classification to apply those training polygons to the entire raster).

[AlbanXhema]

Right now I've just decided to freehand draw everything, I was just hoping there was a way to do it faster and to make it more exact