Change Fractal Colors to nuances of red

Hello,

I have a series of fractals in RGB, such as the one uploaded here, and I would like to change their colors to only nuances of red, black and white. So that the structure of the image would remain in white or black and the filling will be only red. Any suggestions would be welcome.

[Adam Danz]

See colormap

https://www.mathworks.com/help/matlab/ref/colormap.html

[Walter Roberson]

Possibly rgb2ind() followed by using a different colormap() with ind2rgb()

Answer 1

[Subhadeep Koley]

Building a custom colormap might solve your issue. Similar question can be found here.

Tweaking the "hex" vector as shown below could help solve the issue.

a=imread('image0006v1.bmp');
%modify the sample points inside vec and put the hex code for as many different shades of red you want
vec = [      100;       83;       68;       44;       30;       15;        0];
hex = ['#FF6347';'#DC143C';'#FF0000';'#B22222';'#B22222';'#8B0000';'#800000'];
raw = sscanf(hex','#%2x%2x%2x',[3,size(hex,1)]).' / 255;
%N =100;
N = size(get(gcf,'colormap'),1) % size of the current colormap
map = interp1(vec,raw,linspace(100,0,N),'spline');
rgbImage = ind2rgb(a, map);
imshow(rgbImage);

[Adam Danz]

The RGB vectors may be easier to work with. For example, here's a colormap that fades from black to red.

colorMap = [linspace(0,1,256)', zeros(256,2)]
colormap(colorMap);