Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.graphics.apps.gnuplot > #3461

Re: Overlapping/Merge two density plot red and green scale using gnuplot

Show all headers | View raw

On 11/14/2016 2:59 PM, Graziani Candiotto wrote:
> Hello People,	
>
> I would like to ask the follow question.
>
> How can I overlap/merge two density plot (in attach) using gnuplot. One image is in red scale and the other is in green scale.
>
> Density plot in red and green scale
>
> In theses two images the lowest value is white (background) and the highest values are represented by pure red [ RGB (255,0,0) ] and green [ RGB (0,255,0) ] scale.
>
>
> I looking for a way two overlap this two images, such that intersections are a combination of red and green to give a yellow intensity dependent on the "red" and "green" values.
>
> In summary I need that resultant image had red, green and yellow colors.
>
> I've tried some methods to interpolate the two images, but the resultant image is:
>
> interpolation
>
> I was expecting a light yellow [ RGB (255,255,0) ] color resultant but I get a dark yellow [ RGB (127,127,0) ]. How can I solve this problem using gnuplot.
>
> The data files and gnuplot script for the red and green images are available in the link below
>
> www.dropbox.com/s/teucom4uco283gp/overflow_example.tar.gz?dl=0
>
> Thanks for attention.
>

not really into downloading stuff ...

assuming a perfect additive RGB device/colorant system

R=R
G=G
B=B

simple mixing
(R,G,B)= R/(R+G+B) + G/(R+G+B) + B/(R+G+B)

round to nearest drive value, etc..
infinite drive is 255, have to catch this in code

to get complementary colors
cyan=255/R
magenta=255/G
yellow=255/B

round to nearest drive value, etc..
infinite drive is 255, have to catch this in code

if you want to device independence or device "consideration" you will 
need to add CIE, ICC, CIECAM, etc. calculations



-- 
dale | http://www.dalekelly.org

Back to comp.graphics.apps.gnuplot | Previous | Next — Previous in thread | Next in thread | Find similar

Thread

Overlapping/Merge two density plot red and green scale using gnuplot Graziani Candiotto <graz13@gmail.com> - 2016-11-14 11:59 -0800
  Re: Overlapping/Merge two density plot red and green scale using gnuplot dale <dale@dalekelly.org> - 2016-11-15 21:13 -0500
    Re: Overlapping/Merge two density plot red and green scale using gnuplot dale <dale@dalekelly.org> - 2016-11-15 21:45 -0500
      Re: Overlapping/Merge two density plot red and green scale using gnuplot dale <dale@dalekelly.org> - 2016-11-16 00:51 -0500
        Re: Overlapping/Merge two density plot red and green scale using gnuplot dale <dale@dalekelly.org> - 2016-11-16 07:41 -0500
  Re: Overlapping/Merge two density plot red and green scale using gnuplot dale <dale@dalekelly.org> - 2016-11-17 21:32 -0500
    Re: Overlapping/Merge two density plot red and green scale using gnuplot dale <dale@dalekelly.org> - 2016-11-18 00:42 -0500
      Re: Overlapping/Merge two density plot red and green scale using gnuplot dale <dale@dalekelly.org> - 2016-11-18 00:46 -0500
      Re: Overlapping/Merge two density plot red and green scale using gnuplot dale <dale@dalekelly.org> - 2016-11-18 21:57 -0500

csiph-web