Pixel Shift when cropping from Ortho (GM Graphics issue?)
StacyL
Global Mapper UserTrusted User
Mike,
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.
Thanks,
Stacy Lunsford
Metro Engineering
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.
Thanks,
Stacy Lunsford
Metro Engineering
Comments
-
Stacy,
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.
Thanks,
Mike
Global Mapper Support
support@globalmapper.com
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