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I would like to make a comparison of mangrove health and cover, between 2008 and 2022, at the scale of a region. For this, I will use a satellite imagery, taken from the plugin : "QuickMapServices" And I'll georeference a Google Earth image (I hope it is feasible and accurate at this scale).

The area's extent is 6 000 000 ha. I have a shapefile with old mangroves patches. Since I cannot clip a WMS, I exported it using the Atlas, and creating a .tif image everywhere I have a mangrove patch. The size of folder with all the raster is 5.6Go.

Then I would like to clip all the rasters, through a shapefile mask (using the mangrove patches shapefile, with 100m buffer). This operation isn't possible, because I would need 1.6To of storage according to QGIS.

And, if I find a way to clip the rasters, I'm planning to use remote sensing to identify mangroves and their environment (I'm planning to use OTB that I know).

Do you think it is possible ? Do you have another approach ? Because for mine, my computer isn't able to do the calculation.

Here is a picture of how it looks like with all the cut Rasters:

Actuel

Giene
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    A WMS service returns a picture of the data you can not reliably extract meaningful information from it - if you require actual data you must use a WFS or WCS endpoint to fetch actual data. – Ian Turton Jan 29 '23 at 14:58
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    I'm saving basemaps from the Atlas, that I use for land analysis. The final goal is to delineate mangrove, using segmentation and other tools from Orfeo ToolBox. It worked on previous analysis (not perfectly, but good, and better than I could manually do). I would like to do the same here, but the amount of data is way larger, so I'm trying to reduce the size of the basemaps by clipping the parts that I need. – Giene Jan 29 '23 at 15:00
  • With GDAL it's possible to clip WMS/WMTS services as well: https://gis.stackexchange.com/questions/315637/qgis-data-frame-clipping-for-basemaps/417363#417363 – christoph Jan 31 '23 at 14:55

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