Project file size - Orthophoto

[Costas]

I would like to ask about the file size of an Agisoft project.

I have noticed that when creating an Orthophoto in a project, the file size of the project gets way too big.
I calculated that the orthophoto itself it takes about 3.2 times bigger in size than the file size of the photos used.

For example:
1) I used 3.220 photos in a project. Their total file size is about 56.3 GB.
2) After i create an Orthomosaic the project's file size skyrockets. The total filesize of the project is 196GB out of which the Orthomosaic is 177GB. (the rest 19GB are the point clouds, Dems etc)

The orthomosaic folder alone is 3.14 times bigger than the photos used. So for this project i need about 196+56 = 252 GB + exports = 270 GB of drive space

The same logic carries on all the projects i make. Currently i have about 50TB of drive space on my PC for all my projects + another 50TB external for backups.
Now i run a project with 7.700 photos that are about 140GB and i expect to have an Orthomosaic folder about 450GB. If i consider point clouds, dems etc i will need about 700GB Drive space to save this project.


Why is that happening?
How Agisoft is tilling the photos to create the orthomosaic?
Can i do something to optimize drive space or it's just how it works?

[Bzuco]

I am not sure, but I think, that orthomosaic file is internaly in uncompressed format, like simple bitmap 8bits/channel.
For example 18Mpix jpeg from camera has around 10MB in highest JPEG quality, it's bitmap equivalent is 51MB... 5 times more. If you make some overlap when taking photos, then 3.2 times bigger orthomosaic seems to be correct and minimal size.

[Alexey Pasumansky]

Hello Costas,

By default not only orthomosaic itself is stored, but also the individually orthorectfied images in images##.zip archives of /orthomosaic/ folder. If you are not planning any manual orthomosaic patching, you can remove them from Metashape interface by right-clicking on the orthomosaic label in the Workspace pane and choosing Remove Orthophotos option from the context menu. Then save the project.

[Costas]

Thank you Alexey for your answer.

I understand that if i remove them before patching then it will be not possible to patch it but for projects that i already did some manual patching and then "Update the Orthomosaic", is it ok to remove the orthophotos as you described or do i lose the patching?

[Alexey Pasumansky]

Hello Costas,

Yes, both is correct:
- Assign Image tool will be available only if orthorectified images are present in the project folder structure.
- after using Update Orthomosaic command orthorectified images could be removed, as all the manual changes would be applied to the orthomosaic.