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davidfrantz
Masked blocks in TSS are assigned 0 instead of nodata value
Maybe related to #26:
When producing TSS with masks in v3.7.8, there are some masked areas that are assigned 0 instead of the nodata value. The issue does not occur when using v3.7.7. We also didn't observe this when Landsat was processed for the same 30x30km tile - same block size (3000) but 30m res instead of 10m.
I wonder what I changed... I guess I will need to implement the CSO fix in each sub-module
Hey @ernstste, did https://github.com/davidfrantz/force/issues/26 ever work? I just made a small test, and it doesn't work for TSA and CSO.
I tried to pin down the issue, and problem is, that data for this chunk are neither read, computed, nor written. I guess that the GeoTiff is sparse, though I do not understand yet why this worked in the past.
This bug was introduced when implementing the custom GDAL options where you can define your own output format and choose your own driver.
Not every driver supports "creating" a dataset, some need to create by copying an existing one. This can be an in-memory dataset, however. And to be most flexible and simplify the code, I followed that strategy for all drivers, i.e.
- create dataset in-memory
- copy dataset to disk
Apparently, this does not work with sparse files somehow... ugh.
I guess I will need to check if the driver can create files, and then work around this by either directly creating or create/copying only if needed.
Ouch. Custom GDAL options come back to bite you again.
I'm pretty sure #26 did work back then. I tried it right after you implemented the fix and the results looked ok.
It might be, that the problem does not consistently surface - you also mentioned that you did not see that issue with Landsat data.
I worked on a fix: https://github.com/davidfrantz/force/commit/d9759f64204a563723ec39f63970928267a77751
I think it solves this issue.
The only thing to mention (and I believe this already did not work before) is that I could not make create/copy drivers work for block-output (like in HLPS). If full files are written, it works, however (like the OVV images in L2PS).