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Convert and analyze image data in a spreadsheet.


Dennis,
Thanks for your ideas. The researcher I am working with just told me the
data is wrong and needs to send me new data and there are other problems
with exactly what their research questions is. So this goes nowhere for now.

Thanks
Vincent Davis
720-301-3003
*Want to get a hold of me?*


*SMS: awesome.phone: ok...*
*email: bad!*


On Thu, Jun 11, 2020 at 1:17 PM Dennis Lee Bieber <wlfraed at ix.netcom.com>
wrote:

>
>         My previous response hasn't made it through the
> gmane<>list<>usenet<>back cycle so I can't "talk to myself"...
>
> On Thu, 11 Jun 2020 07:44:25 -0600, Vincent Davis
> <vincent at vincentdavis.net> declaimed the following:
>
> >Looking for a little advise.
> >I have 6x6 color (CIELAB <
> https://en.wikipedia.org/wiki/CIELAB_color_space>)
> >data in a spreadsheet (color samples of clothing). I would like to
> >visualize this as an image on a per channel (l,a,b) and as a color image.
> I
> >can read the data from the spreadsheet. I am not sure the path a should
> >choose from there. I think the path is to read this data into a numpy
> array
> >and use scikit-image.
> >
>
>         I'm going to speak blasphemy and mention the R statistics package.
> It
> has
>
> https://stat.ethz.ch/R-manual/R-devel/library/grDevices/html/convertColor.html
> which includes L*a*b* as a color space. Though it does not seem to have
> Adobe RGB...
> """
> "XYZ", "sRGB", "Apple RGB", "CIE RGB", "Lab", "Luv".
> """
>
>         Also links to the main page of a source of the math used in
> converting
>
>         It also mentions something that wasn't obvious in other references:
> """
> The Lab and Luv spaces describe colors of objects, and so require the
> specification of a reference ?white light? color. Illuminant D65 is a
> standard indirect daylight, Illuminant D50 is close to direct sunlight, and
> Illuminant A is the light from a standard incandescent bulb. Other standard
> CIE illuminants supported are B, C, E and D55. RGB colour spaces are
> defined relative to a particular reference white, and can be only
> approximately translated to other reference whites.
> """
>
> ... hence conversions from L*a*b* to, say, sRGB, will differ based upon
> what illumination reference is used!
>
>
>
> --
>         Wulfraed                 Dennis Lee Bieber         AF6VN
>         wlfraed at ix.netcom.com
> http://wlfraed.microdiversity.freeddns.org/
>
> --
> https://mail.python.org/mailman/listinfo/python-list
>