Pixel Shift when cropping from Ortho (GM Graphics issue?)

StacyLStacyL Global Mapper UserPosts: 34Trusted User
edited April 2009 in Technical Support

When cropping from a one half foot pixel Orthophoto (sid format) from GM, I reloaded the new cropped image (tif format) back into and over the original ortho.

When turning the display off and on of the new image, I noticed a pixel shift of about a pixel width throughout the image but only in certain areas. Shift seems to be linear and constrained to cardinal direction only.

I also tried the above process on a different computers with the same results.

After taking the two images into another software package (AcadMap) the shift is not evident. So It seems to be a graphics only isssue within GM.

Just wanted to make you aware of this.

Please see the attached animated gif file showing the shift.

Stacy Lunsford
Metro Engineering


  • global_mapperglobal_mapper Administrator Posts: 17,238
    edited April 2009

    What you are seeing is likely a result of the default resampling method of nearest neighbor being used, which causes up to a pixel shift when resampling. If you enable interpolation (anti-aliasing) for a layer from the Options dialog in the Control Center prior to export, that should fix issues like this. This is likely enabled by default in ArcMap.

    Let me know if I can be of further assistance.


    Global Mapper Support
Sign In or Register to comment.