How do I go about generating a colormap from a matlab file containing RGB values

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Saba Malik
Saba Malik 2016-5-13
评论： Walter Roberson 2016-5-16
Hi all !
I'm really stuck on a problem I would appreciate help with :
I have a matlab file containing 359 variables where each variable consists of a 360 x 3 matrix of double RGB values . For example , variable 1 looks like this :
1 1 1
1 1 1
1 1 1
1 1 1
1 0.73 1
1 0.76 1
.
.
.
.
.
and so on until row 360 .
My question is how can I go about loading these values into a matrix from which I can generate a colormap?
I have loaded values from a structure into a matrix and represented it as a colormap pretty easily before but my issue here is that I have three RGB values for each row and I don't know how to 'combine' them to get a number which represents a color (if it is even necessary for me to do that).
Many thanks in advance !
Saba

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采纳的回答

Walter Roberson
Walter Roberson 2016-5-13
cmap = unique(YourArray, 'rows');
or, better,
cmap = uniquetol(YourArray, 1, 'ByRows', true, 'DataScale', 0.004);
cmap is now your colormap.
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Walter Roberson
Walter Roberson 2016-5-16
0.004 is slightly less than 1/255. I was aiming to have a change of less than 1/255 be recognized as being the same color.

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更多回答（1 个）

Image Analyst
Image Analyst 2016-5-13
Use the colormap() function after you've displayed your grayscale or indexed image
imshow(grayImage);
colormap(variable1); % variable1 is a 360 by 1 colormap matrix.
colorbar; % Show a colored ramp showing what intensities map to what RGB color.
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Saba Malik
Saba Malik 2016-5-13
Hi - thanks for your reply
My issue is actually getting to the image stage from the values I have in the matlab file . You said 'display your grayscale image' but I wouldn't be able to do that until I generate a colormap from the RGB values in the file
Image Analyst
Image Analyst 2016-5-14
You said you have "a 360 x 3 matrix of double RGB values" - well, that is the exact format that a colormap would take. Is the matrix not a colormap? If no, then what is it?

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