Translating tif rasters to asc taking a long time

Question

I need to use the 19 WorldClim variables in MAXENT, so I have to take the .tif files to .asc files using the translate tool. It's taking forever for me (2% after 2 hours). I've given up. I know its possible, and people use WorldClim for MAXENT, is there a trick I'm missing?

Edit to add: My rasters vary in size from 1 GB to 512 MB. Obviously these are large files, and I expected them to take some time, but maybe not upwards of an entire day. Curiously, when I clipped them to a smaller area of interest, the files came out larger than the untouched version.

Answer 1

As a test to see whether it is faster you can run gdal_translate from the OSGeo4W shell using the instructions here: http://www.gdal.org/gdal_translate.html

Essentially navigate to your directory within the shell and type:

gdal_translate -of AAIGrid  SourceDatasetName.tif OutputDatasetName.asc

This should be much faster than using the translate tool through QGIS. If it is then you can batch the tool using the instructions within this question: How to translate tens of images from a directory as a batch with gdal_translate?

If you don't want asc outputs then you need to change the -of (output format) tag depending on the gdal code (http://www.gdal.org/formats_list.html)

Answer 2

I have been using the translate tool and sometimes, I don't know why, is too slow. You have two options:

• If you can have access to a pc with arcgis, try the tool "from raster to ascii" (ArcToolbox/conversion tools/from raster to ascii). It works like a charm.

• If you have some notions of R (just basics needed) you can try this solution found on researchgate:

  #load library
  library(raster)
  
  #read your file 
  r <- raster(system.file("temp/bio1.grd", package="raster")) 
  
  #export it to asc (ESRI ASCII) 
  writeRaster(r, filename="bio1.asc", format = "ascii", datatype='INT4S', overwrite=TRUE)