[Gdal-dev] gdaladdo with .rrd ignoring compress overviews?

[Frank Warmerdam]

Matt Wilkie wrote:
> Hi gdal, I'm on roll today! Here's another one: Why does gdalinfo report 
> that overviews are compressed with RLC when I asked for LZW? Can only 
> one --config option be used at a time? Or does .rrd not support choice 
> of compression?

Matt,

Erdas Imagine files don't support LZW.  RLC is the only supported
compression (I think).  Frankly, I don't know why it even used the
RLC compression.  I don't see any support for the COMPRESS_OVERVIEW
config option in the HFA/.img/.aux code.

Best regards,

>    gdaladdo --config use_rrd yes --config compress_overview lzw -r 
> nearest 094M.tif 2 4 8 16 32
> 
>    gdalinfo 094M.aux
> 
> Driver: HFA/Erdas Imagine Images (.img)
> Size is 5817, 5714
> Coordinate System is `'
> Corner Coordinates:
> Upper Left  (    0.0,    0.0)
> Lower Left  (    0.0, 5714.0)
> Upper Right ( 5817.0,    0.0)
> Lower Right ( 5817.0, 5714.0)
> Center      ( 2908.5, 2857.0)
> Band 1 Block=64x64 Type=Byte, ColorInterp=Undefined
>   Description = Layer_1
>   Overviews: 2909x2857, 1455x1429, 728x715, 364x358, 182x179
>   Metadata:
>     LAYER_TYPE=athematic
>   Image Structure Metadata:
>     COMPRESSION=RLC




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