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I have a large set of imagery that I created a mosaic from in ArcMap 10.1. I want to use GDAL to create the overviews because arcmap has issues building the pyramids and never seems to complete. I have experimented with using the GDAL command line utilities specifically:

gdaladdo image.png 2 4

The image alone is about 4gb. When creating the overviews using the above command, it generated and overview file over 60 gb in size.

What levels should I include in the command to mimic what ArcMap would create by default?

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    I would create compressed overviews gdal.org/gdaladdo.html gdaladdo -ro --config COMPRESS_OVERVIEW DEFLATE But you make a major mistake by creating a 4 GB mosaic in png format. Create tiled GeoTIFF instead using DEFLATE compression or JPEG compression if you have satellite or aerial images and you do not need lossless quality. – user30184 Sep 1 '15 at 21:18
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    PNG images are DEFLATE compressed so I'm not surprised the overviews come out larger than the original image. Personally I'd use a Mosaic Dataset of the tiled images rather than a single image mosaic and if needed as a single image use the advice of @user30184 and go GeoTIFF with LZ77. As for the pyramids, Esri builds 'appropriate' overviews depending on the size of the image (max 7) which would be 2 4 8 16 32 64 128 and 4 8 16 32 64 128 with the 'skip first' option. Your build pyramids could be struggling trying to decompress and average, you wouldn't have the same problem with a tiled TIFF. – Michael Stimson Sep 2 '15 at 1:42
  • Thanks a lot for the valuable info. I would agree with you on using a mosaic dataset, however in this particular case the person who needs the imagery wants a single file mosaiced image. Either way, I am curious why exactly you both do not recommend PNG format. It is about 1/3 the size of the tiff format, and after incorporating compression into the overviews I am getting a much more reasonable sized overview, however I did only end up using levels 4 8 16 32 64 128. – Michael B Sep 2 '15 at 11:52
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I have worked with external and internal to the large extent . External pyramids are little bit slow then internal one's because the data has to be ready from the external file . GDAL has to read .ovr file.

Pros of external overview:-

  1. Less space to store.
  2. Handy and can be deelte anytime if not required.

Cons of external overview:-

  1. Less Speed 2. takes 15% more size w.r.t. actual data size on hard disk.

Cons of internal overview:-

  1. takes 35% more size w.r.t. actual data size on hard disk.
  2. once created you can remove internal pyramids but space used for internal pyramids will not come back. Ex:- if 300 MB original dataset , we build internal it becomes 415MB , when we remove internal pyramids, size of raster will remains 415MB.
  3. can only be build if data set size don't exceed 4 GB

Pros of internal overview:-

  1. Faster Speed.
  • I think you've mixed your pros and cons for internal overviews – AWGIS Jul 4 '18 at 7:44

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