17.8 GB for a mosaic of an area of 800km2? Isn't it too big?

[MLOPEZ]

Hello,

Why does a mosaic of an area of 800km2 with the information of only 5 bands 10m resolution occupy 17.8GB, ten times more than one original image?? Shouldn’t be smaller??

We also found that the memory needed for a mask of an area of 200km2 with 5 bands was bigger than the original image (2.24 GB vs 1.5 GB). Why??

Why do the products when using Sentinel 2 images occupy more than the original images if the area and the information they contain are much smaller?? We have problems with the space in our computer and need to optimize all the products.

Any help will be much appreciated. Thank you,

[ABraun]

could it be that this is caused by data type and data format?

If the output is GeoTiff file size increases drastically. Sentinel-2 is originally compressed as Integer JPEG2000.
If you convert it to float GeoTiff the increase in file size would make sense.

[marpet]

I’ve calculated some time ago the size of an uncompressed Sentinel-2 L2A product in GeoTiff format.
This explains the huge amount of data you observe.

Resampling L2A products

Running it from the command line will not help. I've calculated the raw size of a L2A product in GeoTiff. It is 243 GB. The reason for this is that we have to use a common data type for all bands. [image] You can reduce the size for example by removing all the view bands for the specific bands and keep only the mean bands. Also you can split your product into 2 products. One for the sun/view bands and one for the other bands. Then the sun/view bands are stored as float32 data type and the othe…

[mengdahl]

Out of curiosity I’d like to know what the size of a global S-2 L2A mosaic would be in GeoTiff

[MLOPEZ]

I saved the mosaic and the mask in SNAP format (.dim). Still don’t undersant why they occupy so much memory. Any idea??