[Gdal-dev] using gdaladdo with tiled tifs

[Jeff Hoffmann]

I have a question about the best way to create overviews in tiled tifs. 
    I've created my tifs with a block size of 512x512 with the 
understanding that this should help with performance if I'm pulling 
small blocks (say 500 x 500 pixels) from much larger images (say 20k x 
20k pixels).  So when I created that tif, I passed a bunch of command 
line configuration options to gdal_translate to get the tiling I 
selected, but when I did overviews, I just did a plain "gdaladdo my.tif 
2 4 8 16 32" without any options.  Should I be telling gdaladdo all of 
the same tiling options as when I created the tif?  Or does it just know 
to use the same configuration as when it was created?  Or doesn't it 
matter?  Also, I've chosen to compress the original tif because most of 
the usage will come from the overviews.  Do I need to tell it not to 
compress the overviews or is that the default and I actually have to 
tell it to compress the overviews?

-- 
Jeff Hoffmann
Head Plate Spinner
PropertyKey.com