How to sensibly digitise this raster, scriptably, in ArcGIS

Question

I have the raster below which I want to convert to a set of vector lines:

As you can see, there are small breaks in the lines and some bits are double-width. I want to be able to reliably import these sort of images to a vector in ArcGIS.

I've spent a lot of time trying to get tools like Integrate, Extend Lines, Trim Lines and Unsplit Lines to do what I want, but I just can't seem to achieve it. I guess this problem must have been experienced before, does anyone have any ideas for a workflow that would do what I want?

I thought of maybe trying to clean up the raster before-hand, but I'm not sure how to go about that. Again, any ideas would be much appreciated.

Answer 1

Scan2cad has a free set of Image cleanup tools. You can dilate the Pixels to close the gaps, then thin the pixels. Despeckle,etc.

Bring the image into ArcGIS, raster to polyline.

To find the remaining gaps, save the line end-points as points (feature vertices to points). Run Near, setting a max search distance. Arc 10 has more advanced snapping tools. You can use your points file that have another end point within a distance to select your lines for snapping.

I cannot find an ESRI tool that creates polylines from points. You might be able to adapt this, http://arcscripts.esri.com/details.asp?dbid=13147