[gdal-dev] Question regarding overviews

[Frank Warmerdam]

lee heng hock wrote:
> Hi,
> 
> I like to clarify my understanding on the concept of overviews.
> 
> Say if i have a geotif map 300 pix by 300 pix, then if i build a 
> overview giving a decimation factor of 2, I will get a map 150 pix by 
> 150 pix. This is so because 1/2 of the amount of pixels along its width 
> and 1/2 of it along its height are being thrown away, thus resulting in 
> a map with 1/4 the original map size in terms of total number of pixels.
> 
> Did I get my concept right?

Heng Hock,

Yes, this is correct.

Best regards,
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