I want to create a line shapefiles of white roads from the raster file (screenshot1) using ArcGIS:Raster contains roads. My idea is to use ArcScan toolbar, but first of all I need to classify roads pixels values from raster. For that I have used ISO Unsupervised classification tool with a number of 30 classes. The results are not good for me because I got the unclear pixel values which are unusable for ArcScan vectorisation (screenshot2): Classification results Of course, if I have a clear pixels defining the roads I will use Reclassify tool to filter get just two pixel values (one which I need and one which don`t). Now I need to know is there any way to solve my problem?

  • Are these roads available for download using Open Street Maps? If not, why not just create a new shapefile and digitize the roads yourself. – GBG Sep 11 '17 at 17:48
  • @GBG No, this is a historic map of Netherland from 1930. – user104851 Sep 11 '17 at 17:50
  • @user107851- If it is too much area to digitize (your best option) you could open the image in GIMP (or photoshop). Use the selection tools to recolor the areas you want white, and the rest black (lots of help on line). Bring the image back into ArcGIS and reclassify to 1 or NoData, then convert to line. – GBG Sep 11 '17 at 17:55
  • @GBG Very interesting solution. Great! I have GIMP. Is there any tool which can to recognise white areas between black lines (wanted roads)? – user104851 Sep 11 '17 at 17:59
  • @user107851 You can set the selection tool to only select continuous areas of white (or near white depending on the threshold settings) but it looks like you will get mixed results since not all of the road whites are connected. You will need to add to your selection in that case. – GBG Sep 11 '17 at 18:22

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