I processed a 9000 image data set. At first I processed it as 5 seperate projects. 34GB in total between the 5 GeoTiffs. They all opened up eaily in Global Mapper.
I then processed all 9000 images in the same project and exported as a tiled GeoTiff. 24GB in total. It’s so slow in Global Mapper that it is unusable and often freezes the program.
I thought the tiled export would be easier to open in GM. Any ideas why this is happening?
Hi highexposure,
This is a little difficult to troubleshoot, but it could be due to the tile size. Have you tried exporting different sizes?
Highexposure,
I believe the reason the first one opened quickly in global mapper is because you exported a single geotiff from Pix4d (for each), and that Pix4d generates pyramids/overviews in those orthos. When you use the tiled option for export, it does not generate overviews/pyramids. (I’m pretty sure that’s the way it works, but not 100%). Without overviews, that imagery will be slow to load each time you zoom and pan around.
You can fix that by batch-processing your tiles from the 24gb ortho in global mapper, exporting new tiles that include the option to generate pyramids/overviews.
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Use the metadata button in GM to check whether or not your imagery layer has overviews:
To add overviews to your 24gb of tiles, use the batch processing tool in global mapper.
(There’s no option in this menu to generate overviews, but I’m pretty sure I remember that it does it anyways in this dialogue)
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Plan B:
And just in case I’m wrong and the batch processing tool DOESN’T generate overviews automatically, the option is present in the export to geotiff tool (and you’d have to export manually for each tile with this option)
Thank you! I will try this out and let you know how it goes.
@Derrick_Westoby1 thank you for your help and @highexposure how did it go?
I confirm that we only create pyramids for the full orthomosaic export, not for the tiled export.
We implemented the tiled export to be compatible with applications that cannot open the full image. In this case, it seems that Global Mapper can open the full orthomosaic. Can you confirm that you can continue opening the single/full orthomosaic with Gobal Mapper or can you provide more details on why you would be interested in opening the tiles?
