Exporting large orthomosaics

[james_AU]

Dear all,

After having searched the forum for a similar query and having asked a few colleagues, I would be interested to know how one works around the following problem.

For the case of large models of around 600+ cameras, when trying to view an exported orthomosaic in JPEG or TIFF (source cameras are in JPEG) in an image viewing programme, including Preview  and Photoshop (on Mac), I find that whilst I can view the exported orthomosaic from the global viewpoint (ie the whole surface), I can not zoom in to inspect details. A blank screen is displayed instead.

There are no problems viewing the orthomosaic in the  Metashape / Photoscan GUI itself.

As I am increasingly processing larger and larger models, this is becoming more of an issue than has been previously the case.

Is there a reason for this? Is there a solution? I must surely not be the only one who has encountered this...?

Kind regards,


James

[Alexey Pasumansky]

Hello James,

What are the common dimensions of the exported orthomosaics?

I think that it may be more convenient to use dedicated GIS applications for orthomosaic display purposes (like Q-GIS, Global Mapper, ArcGIS and etc.) or even use online platforms.

[jrp]

Consider using the "split into blocks" option in the export window. This will split the final ortho into a grid of more managable sized tiles.

This may not work with your workflow, but it would certainly help with the direct problem you describe. It may also be workable to output these for preview purposes and then export a single huge file for the finished result.

[aggieair]

Does checking the "Write BigTIFF file" in the Export Ortho window work for your purposes? I've exported 50GB mosaics in one piece this way, but I use ArcGIS to view the images. I've used Split in Blocks as well (you'll have to play with the pixel sizing, I've used 5000 or 10,000).