[GRASS-user] Matching Histograms for Aerial Photography?

[Moritz Lennert]

On 20/06/17 11:06, Jeshua Lacock wrote:
>
> Greetings,
>
> I am struggling to match histograms for various US states NAIP 1-meter
> aerial photography.
>
> It appears that each state shown here has been equalized for each
> individual state except for Nevada and Arizona.
>
> I have tried using r.rescale.eq with many different parameters but I
> cannot really get Nevada and Arizona to roughly match the intensities of
> the rest of the states. It is difficult to guess values that match
> because the images are quite large and when I attempt to use a thumbnail
> (say at 50m resolution), the parameters used for the 50m thumbnail don’t
> match when using the full resolution image.
>
> Can anyone recommend how I might be able to get the histograms to match?

You can try the addon: i.histo.match. You can install it with g.extension.

Moritz