PCwin: grayscale luminance

1
Is there a recromended method to normalize the luminance of several grayscale images to be used in an experiment? I imagine this might involve adjusting the mean or RMS of the clut values used for each grayscale image, however I thought that I would first ask in order to avoid possibly re-inventing the wheel.

Best,
Kevin Guise
2
Hi Kevin,

Typically, one can simply equalize the luminance and RMS contrast of
all the images by the following:

MyPic = (MyPic - mean2(MyPic))./std(MyPic);
MyPic = (MyPic .* DesiredLuminanceStd) + DesiredLuminanceMean;

You may have to do some range-clipping after this as well.

[Check my syntax above, as this is just quick and off the top of my
head...]

Charles.


On Thursday, Nov 18, 2004, at 11:35 America/Montreal, Kevin Guise wrote:

>
> Is there a recromended method to normalize the luminance of several
> grayscale images to be used in an experiment? I imagine this might
> involve adjusting the mean or RMS of the clut values used for each
> grayscale image, however I thought that I would first ask in order to
> avoid possibly re-inventing the wheel.
>
> Best,
> Kevin Guise
>
>
>
>
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----------------------------------------------------------------------
Charles A. Collin, Ph.D.
Université d' Ottawa
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