Call to Extract Contents from Cell Array not Equal to Value in Cell Array

Hello,

I am trying to extract the contents of a cell array to implement in my code (pasted below); however, the extracted contents add one more value than there is in that index of my cell array,

Index 3 of my array, "offY1" pasted directly into my cell array yields 870 . . . 2405

While a call to extract the value from my cell array "offY1{3}"[ yields 870 . . . 2406

I am very confused because I don't understand how a call directly to my cell array can result in a value different than the value in my cell array.

*** Code Below intends to blend the intersection of four stitched images**

clearvars
clc
close all

I1 = imread('I3.png');
I1 = rgb2gray((I1));
I2 = imread('I2.png');
I2 = rgb2gray((I2));
I3 = imread('I4.png');
I3 = rgb2gray((I3));
I4 = imread('I1.png');
I4 = rgb2gray((I4));

figure; imagesc(I1);
figure; imagesc(I2);
figure; imagesc(I3);
figure; imagesc(I4);

offsetY1 = 4;
offsetX1 = 732;
offsetY2 = 870;
offsetX2 = 1099;
offsetY3 = 773;
offsetX3 = 289;

% Unblended Full Image (2308, 3010)
fullIm = zeros(size(I1,1) + offsetY3 -1, size(I4,2) + 963 - 1, 'uint16');
% (4:1536, 732:2779)
fullIm(offsetY1:size(I1,1) + offsetY1 -1, offsetX1:size(I1,2) + offsetX1 - 1) = I2;
% (1:1536,1:2048)
fullIm(1:size(I1,1), 1:size(I1,2)) = I1;
% (870:2405,963:3010)
fullIm(offsetY2:size(I4,1) + offsetY2 -1, 963:size(I4,2) + 963 - 1) = I4;
% (773:2308,289:2336)
fullIm(offsetY3: size(I1,1) + offsetY3 -1, offsetX3:size(I3,2) + offsetX3 - 1) = I3;
figure; imagesc(fullIm);

% *** Need to edit from video tutorial below ***

% Blended Full Image (2308, 3010)
blendedFullIm = zeros(size(I4,1) + offsetY2 -1, size(I4,2) + 963 - 1, 'uint16');
blendedFullImNum = nan(size(I4,1) + offsetY2 -1, size(I4,2) + 963 - 1);
blendedFullImDen = nan(size(I4,1) + offsetY2 -1, size(I4,2) + 963 - 1);

% Averaging Mask
avgImFill = ones(size(I1));

I = {I1, I2, I3, I4};

offY1 = {offsetY1:size(I1,1) + offsetY1 - 1, 1:size(I1,1), offsetY2:size(I4,1) + offsetY2 -1, offsetY3: size(I1,1) + offsetY3 -1};
offX1 = {offsetX1:size(I1,2) + offsetX1 - 1, 1:size(I1,2), 963:size(I4,2) + 963 - 1, offsetX3:size(I3,2) + offsetX3 - 1};
for ti = 1:length(I)
    % Blending Mask
    BW = false(size(I{ti}) - 2);
    BW = padarray(BW, [1,1]);
    ED = bwdist(BW);
    %setting up numerator/denominator
    blendedFullImNum(offY1{ti},offX1{ti}) = nansum(cat(3, blendedFullImNum(offY1{ti},offX1{ti}),ED.*double(I{ti})),3);
    blendedFullImDen(offY1{ti},offX1{ti}) = nansum(cat(3, blendedFullImNum(offY1{ti},offX1{ti}),ED),3);
end
blendedFullIm = blendedFullImNum / blendedFullImDen;
figure; imagesc(blendedFullIm);

Answer 1

[DGM]

Oof. I didn't expect this. Can you find the tiny change I made here (other than line wrapping)?

offY1 = {offsetY1:size(I1,1) + offsetY1 - 1, ...
    1:size(I1,1), ...
    offsetY2:size(I4,1) + offsetY2 - 1, ...
    offsetY3:size(I1,1) + offsetY3 - 1};
offX1 = {offsetX1:size(I1,2) + offsetX1 - 1, ...
    1:size(I1,2), ...
    963:size(I4,2) + 963 - 1, ...
    offsetX3:size(I3,2) + offsetX3 - 1};

All I did was add some extra spaces. Consider the example

{1:10 -1}

ans = 1×2 cell array
    {[1 2 3 4 5 6 7 8 9 10]}    {[-1]}

{1:10 - 1}

ans = 1×1 cell array
    {[1 2 3 4 5 6 7 8 9]}