HI All ,Here i want to Reshape 2D images into 1D image vectors , why i get this error ? Error using '?? Transpose on ND array is not defined. Error in testauto (line 14) temp = reshape(img',r*c,1); .please help its urgent Thanks.

clear all close all clc

path = dir('e:\testImage\*.png'); X = [];

 n = length(path);
for i = 1 : n
    file = strcat('e:\testImage\',path(i).name);
    img = imread(file);
%     figure,imshow(img);
    [r,c] = size(img);
    temp = reshape(img',r*c,1);
    X = [X temp]; 
end

[Jan]

• Please format your code properly. It is not difficult. See instructions
• Omit the brute clearing header clear all close all clc. It is inefficient and a bad habit. As soon as you will work with different GUIs, you will hate this darn auto-closing.
• Do not use "path" as a name of a variable. This is an importanmt function of Matlab and it is hard to predict what might happen during debugging.
• Use fullfile instead of strcat to join path names.
• When you write in the forum, that you get an error message, post a complete copy of the message.
• Use the debugger to examine the problems: The error message is clear: you try to transpose a multi-dimensional array. With the debugger you can find out the dimensions of img. Most likely it is a 3D RGB image.

[Enayat Ansari]

Thanks @Jan_Simon your instruction is helpful

[Walter Roberson]

http://www.mathworks.com/matlabcentral/answers/29922-why-your-question-is-not-urgent-or-an-emergency

Answer 1

[Ahmet Cecen]

Not enough information, but it is likely that the image you are reading is a color image and is actually r by c by 3. I will also speculate you probably want to do:

img = rgb2gray(img);

[Enayat Ansari]

Thanks @Ahmet_Cecen for your answer.but there is new error with this Error using horzcat Dimensions of matrices being concatenated are not consistent.

[Enayat Ansari]

i just want to compare test image with all database images by applying Principal Components (eigenvectors)

[Jan]

When this is your purpose, "[X temp]" might not be useful. When the images have different sizes, this command must fail in addition.

[Enayat Ansari]

so what is the right way to store temp(which is now 1D array) into a matrix.help me i am pretty beginner

Answer 2

[Greg]

The error tells you exactly where the problem is: transposing an ND array on line 14. More specifically, the single tick (') operator is matrix transpose. Replace "img'" with "img". temp = reshape(img',r*c,1);

Better way to convert ANYTHING into a single column vector is "temp = img(:);"

[Enayat Ansari]

Thanks @Greg