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How to rewind the curve by 180 degrees?

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Veronika
Veronika on 24 Apr 2017
Commented: Veronika on 24 Apr 2017
Dear all,
I created curve by fourier_fit function in figure, but I would like to opposite direction (Rotate the curve by 180 degrees). I don´t know, why is curve plotted like this. I attach original image and also Model.m, which I created fourier_fit function. This is my code:
fontSize = 15;
% baseFileName = '110.jpg';
baseFileName = 'thorax-mdl.jpg';
folder = pwd
fullFileName = fullfile(folder, baseFileName);
% Načtení obrazu.
grayImage = imread(fullFileName);
grayImage_pater = imread (fullFileName);
% ***
[rows, columns, numberOfColorChannels] = size(grayImage);
if numberOfColorChannels > 1
% Máme barevný obraz, musíme ho převést na černobílý = vybereme zelený kanál
grayImage = grayImage(:, :, 2); % zelený kanál
end
eq_grayImage = histeq(grayImage);%ekvalizace pomocí histogramu obrazu
[rows, columns, numberOfColorChannels] = size(grayImage_pater);
if numberOfColorChannels > 1
% Máme barevný obraz, musíme ho převést na černobílý = vybereme zelený kanál
grayImage_pater = grayImage_pater(:, :, 2); % zelený kanál
grayImage_pater(425:end, :) = 0;
end
eq_grayImage_pater = histeq(grayImage_pater);
thresholdValue = 170;
binaryImage = grayImage < thresholdValue;
% Odstranění okolí.
binaryImage = imclearborder(binaryImage);
% Vyplnění otvorů.
binaryImage = imfill(binaryImage, 'holes');
se = strel('line',5,100);
%binaryImage= imdilate(binaryImage,se);
% Práh pro vytvoření binárního obrazu páteře.
bodyMask = grayImage > 128;
% Get rid of white surround.
bodyMask = imclearborder(bodyMask);
% Extract the largest blob only.
bodyMask = bwareafilt(bodyMask, 1);
binaryImage_pater = bodyMask & (grayImage > 220);
% Fill holes.
binaryImage_pater= imfill(binaryImage_pater, 'holes');
binaryImage_pater = bwareaopen(binaryImage_pater,197);
%Find areas.
labeledImage = bwlabel(binaryImage_pater);
se = strel('line',5,100);
%binaryImage_pater= imdilate(binaryImage_pater,se);
%Práh pro vytvoření binárního obrazu okolí
thresholdValue = 180;
binaryImage_okoli = eq_grayImage > thresholdValue;
% Odstranění okolí.
binaryImage_okoli = imclearborder(binaryImage_okoli);
% Vyplnění otvorů.
binaryImage_okoli = imfill(binaryImage_okoli, 'holes');
% Vymazání menších otvorů.
binaryImage_okoli = bwareaopen(binaryImage_okoli, 750);
se = strel('line',5,100);
Npts1 = 20; % počet bodů interpolovaných hranic
Ncomps = 20; % počet fourierových komponentů
shape.thorax=Model(binaryImage_okoli,Ncomps,100);
figure()
tmp=shape.thorax{1};
se = strel('square',5);
erodedBW = imerode(binaryImage_okoli,se);
shape.thorax=Model(erodedBW,Ncomps ,30);
tmp = shape.thorax{1};
plot(tmp(:,2), tmp(:,1), 'o-b')
Can you advice me? Thank you for your answers.

  4 Comments

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Veronika
Veronika on 24 Apr 2017
I think, that imrotate is the right choice, but I don´t know how to use it for curves. Can you advice me?
Rik
Rik on 24 Apr 2017
You can't, unless you convert the figure to an image (DON'T do that).
Think really hard about what you want on each axis, and you will be fine. Look at the differences between the output for the lines below.
plot(tmp(:,1), tmp(:,2), 'o-b')
plot(tmp(:,2), tmp(:,1), 'o-b')
plot(tmp(:,1),-tmp(:,2), 'o-b')
plot(tmp(:,2),-tmp(:,1), 'o-b')
plot(-tmp(:,1), tmp(:,2), 'o-b')
plot(-tmp(:,2), tmp(:,1), 'o-b')
plot(-tmp(:,1),-tmp(:,2), 'o-b')
plot(-tmp(:,2),-tmp(:,1), 'o-b')
Veronika
Veronika on 24 Apr 2017
Thank you it helps me so much!

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