Global Mapper v25.0

Mosaic multiple orthos

wayner
wayner Global Mapper User
I have done this a million times in GM but just wondering if there were other ways that are better.  I have multiple aerials that I am displaying and want to blend them together where they overlap.  I usually use the lighten method and turn the background to black then export to create one image.  The problem is you may get blurry aerials where the overlap is.  Is there another way way you can just clip the edges and have no overlap at all.  Let me know if you need more clarification.  I seem to remember in the early days of GM that I would simply get rid of the black borders and whatever image is on top is there.  That hasn't worked for me in a long time.  Thanks, Wayne

Answers

  • hennie
    hennie Global Mapper User Trusted User
    Hi Wayner,
    What I usually do is to create area polygons for the areas per photo that I want to keep. With this area(-s) selected, I then select the photo layer(-s) and under "Options" use the function "Cropping" and "Crop to selected polygons". The resultant image can then be exported. This does not affect the original photo and works like a charm.
    Btw. I am still using V17. Regards, Hennie.
  • Hi Hennie, I am having a real issue understanding how to clean up the edges of my orthomosaic using GlobalMapper.
    All I want to do is draw a line around my ortho and crop out the edges and create a clean straight image border.
  • hennie
    hennie Global Mapper User Trusted User
    Hi Wayner,
    My workflow is:
    1. Open the ortho in GM
    2. With the Edit Tool, Create area/polygon features/Area - create new area feature
    3. Create your box along the outer edge the way you would want to crop the image.
    4. Still with the Edit Tool, select this area.
    5. Open the Overlay Control Center and highlight the ortho.
    6. At the bottom of the Overlay Control Center, click on Options.
    7. Choose the tab Cropping.
    8. Near the bottom, choose Crop to currently selected polygon and then OK.
    9. Only the cropped portion of the ortho should now be visible.
    10. Either save the workspace or export the image to a new file.
    11. The original image will remain unchanged, but you will have a new image cropped to the boundaries you specified if you have exported the file.
    12. Should you want to revert the action, just go back to the Overlay Control Center/Cropping and choose No Cropping.
    Regards, Hennie