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I have a line shapefile in ArcGIS 10.1 (road shapefile) in WGS datum but they are not exactly placed as in the Satellite image. Is there a way to adjust all those lines to places on Arial image?

  • Can you please supply more information such as what type of satellite data you are working with and how the vector data were derived? – Aaron Feb 3 '15 at 19:38
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Provided the Aerial Image is accurate to your project needs and you have re-projected the Line Shapefile to match the spatial reference of the Image, you can use the Spatial Adjustment Toolbar to get started with some semi-automated fixes to your line data.

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Inacurracy is a way of life for the GIS professional. Depending on the source of your roads they could be many metres from their correct location; normally data comes with metadata which should contain a date and an approximate accuracy figure. For example 250k data will be mostly within 125 metres of its' correct location, conversely GPS tracklogs will usually be within 5 metres of the true location.

As the roads were probably drawn (digitized) from a different image at a different time or possibly even GPS recorded they will be different to what is on your satellite image, this is known as temporal change.

You have options:

  1. Redraw the roads using the ones you've got as a reference (long time).

  2. If you're sure the roads are accurate then transform the image to match your roads using GeoReference (not 100% match)

  3. If you are sure the image is correct then warp the roads to match the image using Spatial adjustment toolbar (rubber sheet) (still not 100% match).

  4. Accept that this is the way that it is and draw your roads with a thick line so map users can't tell that they're slightly off.

You have to make a decision based on how inaccurate the roads are, how much you trust each source and how much time/effort you are prepared to invest on getting the data to match.

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