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I am dealing with some very large geotiff files (the whole of Canada at a 250m resolution) and is having trouble to extract the pixels value as I need to do some calculations for mapping ecosystem services (carbon,timber volume, biodiversity etc.). To do so, I need all the pixel value and we have around 4.37 billion raster pixels across Canada. I have tried Python code or convert from raster point but could not success. Then I tried to clip the raster by provenance but it only convert ~ 1/6 part of BC afterward it stopped working.

Can anyone help me to resolve this problem?

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    Do you need to extract pixel values with certain polygon zones? Have you tried Zonal Statistics as Table?: resources.arcgis.com/en/help/main/10.2/index.html#//… – Aaron Sep 23 '15 at 19:57
  • Maybe try Raster to ASCII file? – Pete Sep 23 '15 at 20:58
  • Do you have the spatial analyst extension? – jbosq Sep 23 '15 at 22:19
  • Aaron: Thanks for your suggestion. I tried but it did not work, gave a error and saying only single band integer raster dataset is a valid input. Our pixel type is floating point. It would be highly appreciated if you could give some other idea. – Amalesh Dhar Sep 23 '15 at 22:46
  • Pete: Thanks for your comments but it did not work either. When I convert from raster to ACSII got 0.9999 value for all cells. – Amalesh Dhar Sep 23 '15 at 22:49
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First of all I would copy the raster data to a file geodatabase, assuming it is a geotiff or something comparable. ArcGIS a lot faster using a geodatabase.

In a second step I would use map algebra to multiply the raster with 1000.

In a third step you can now save the raster as 16 bit integer (or other integer format needed for you data precision).

By using step 2 and 3 you can get rid of float and keep the precision. Additionally you will be able to use the extract values by point tool.

  • Generic Militzer: Thank you very much for your suggestion. I can go up to 2nd steps. In third steps, when I wanted to save the raster as 16 bit integer but I could not find it (16 bit integer). I am using ArcGIS 10.1. Could you please give me bit details suggestion about it. – Amalesh Dhar Sep 28 '15 at 22:58
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If you need the value of each single pixel then you could try to create a fishnet with the cell size equal to the pixel extent and then use "Zonal Statistics as Table" to give you only the sum.

This may take a while though.

  • M.Wong: Thanks for your suggestion. I have tried but it did not work. – Amalesh Dhar Sep 28 '15 at 22:54

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