Calculating mean for lines generated from Hough Transform

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Hello everyone,
I'm trying to determine the average RGB colour of lines detected in an image through a Hough transform. I have calcuated the mean of each individual line successful, but I want the mean of all of the lines that are found. The amount of lines could change each time.
for k = 1:length(lines)
xy = [lines(k).point1; lines(k).point2];
plot(xy(:,1),xy(:,2),'LineWidth',2,'Color','green');
% Plot beginnings and ends of lines
plot(xy(1,1),xy(1,2),'x','LineWidth',2,'Color','yellow');
plot(xy(2,1),xy(2,2),'x','LineWidth',2,'Color','red');
% find average road colour - get all co-ords between endpoints
[x, y]=bresenham(xy(1,1),xy(1,2),xy(2,1),xy(2,2));
LineCoOrds{k}=[x, y];
% Get RGB values for these points & their mean
P{k} = impixel(I,x,y);
Meanpix{k}=mean(P{k});
end
I have tried methods such as below, but havent got it quite right.
TotalMeanPixel=cellfun(@mean, Meanpix);
I'm fairly new to Matlab so any help is appreciated a lot.
EDIT - Just to clarify, I want the mean of each individual column, e.g. first column, for all the cells in Meanpix, so I ended up with one value for RGB. I need the average colour of all the lines detected.
Many thanks!
Liz

Accepted Answer

Paul
Paul on 12 Feb 2014
Edited: Paul on 12 Feb 2014
Maybe something like this is what you need:
mean_vec=[];
for ii=1:length(Meanpix)
x=cell2mat(Meanpix{ii});
col1 = x(:,1);
mean_vec=[mean_vec; col1];
end
TotalMeanPixel=mean(mean_vec)
  4 Comments
Paul
Paul on 13 Feb 2014
You can do this too which is easier:
mean_mat=[];
for ii=1:length(Meanpix)
x=cell2mat(Meanpix(ii));
mean_mat=[mean_mat; x];
end
TotalMeanPixel=mean(mean_mat);
R_mean=TotalMeanPixel(1);
G_mean=TotalMeanPixel(2);
B_mean=TotalMeanPixel(3);

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