Get coordinates (x, y) all pixels of a particular column in the area above the boundary line ?

I have extracted the NFL layer of retina OCT image as shown below: Now I am doing macular hole depth mining, but in depth extraction algorithm I need to get coordinates (x, y) all pixels of a particular column in the area above the red boundary line. So how to do that? Help me please

This is the algorithm I'm working on:

% Initialization Steps.
clc;    % Clear the command window.
close all;  % Close all figures (except those of imtool.)
clear;  % Erase all existing variables. Or clearvars if you want.
workspace;  % Make sure the workspace panel is showing.
format long g;
format compact;
fontSize = 15;
markerSize = 4;

%[filename, pathname] = uigetfile({'*.*'},'File Selector');
%if ~isequal(filename,0)
%fullname = strcat(pathname,filename);
I=imread('MH2.jpeg');
%else
% msgbox('Ban chua chon anh?')
%end
Id = size(I);
if length(Id) == 3
    B0 = rgb2gray(I);
else
    B0 = I;
end
B0 = imadjust(B0);
k1 = fspecial('gaussian', [5 5], 2.5);
Ic = imfilter(B0,k1);
figure(1),subplot(3,3,1), imshow(I);
title('anh goc');
figure(1), subplot(3,3,2), imshow(B0);
title('anh tang tuong phan');
figure(1), subplot(3,3,3), imshow(Ic);
title('anh loc gaussian');

%loc trung vi
I_m = medfilt2(B0,[3 3]);
figure(1),subplot(3,3,4), imshow(Ic);
title('anh loc trung vi');

%anh nhi phan
thresholdValue = 60;
bw = Ic > thresholdValue;
bw = bwareafilt(bw, 1);
figure(1),subplot(3,3,5), imshow(bw);
title('anh nhi phan');

%dong hinh thai
se = strel("disk",10);
C1 = imclose(bw, se);
figure(1),subplot(3,3,6), imshow(C1);
title('dong hinh thai');

%khai thac ranh gioi
[A,L,N] = bwboundaries(C1);
figure(1);
subplot(3,3,7); 
imshow(C1); hold on;
title('khai thac ranh gioi');
for k=1:length(A)
    boundary = A{k};
    len(k) = (max(boundary(:,2))-min(boundary(:,2))).^2+(max(boundary(:,1))-min(boundary(:,1))).^2;
    if(k > N)
        plot(boundary(:,2), boundary(:,1), 'g','LineWidth',1.5);
    else
        plot(boundary(:,2), boundary(:,1), 'r','LineWidth',1.5);
    end
end

%lựa chon ranh gioi
[~,ind] = max(len);
Boundary = A{ind};
figure(1);
subplot(3,3,8); 
imshow(C1); hold on;
plot(Boundary(:,2), Boundary(:,1), 'r','LineWidth',1.5);
title('Lua chon ranh gioi dai nhat');

%trich xuat lop NFL
b1 = bwperim(C1);
b1(:,[1:2 end-2:end]) = 0;
b1 = logical(b1);
[B,M,N] = bwboundaries(b1);
for k=1:length(B)
    boundary = B{k};
    len(k) = (max(boundary(:,2))-min(boundary(:,2))).^2+(max(boundary(:,1))-min(boundary(:,1))).^2;
end
[~,ind] = max(len);
Boundary = B{ind};
figure(1);
subplot(3,3,9); 
imshow(C1); hold on;
plot(Boundary(:,2), Boundary(:,1), 'r','LineWidth',1.5);
title('trich xuat lop NFL');
%trich xuat dac trung do sau

[Image Analyst]

OK, but do you have a specific question? Or error message? Anything wrong with your code?

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