MATLAB: Return value of rgb2gray

Image Processing Toolboxmatricesmatrixreturn valuergb2gray

Hi,

For a given image, does rgb2gray return a mxnx3 matrix or mxn when it eliminates hue and saturation? The documentation is not clear on this.

Thanks

Best Answer

It returns an MxN numeric array.

Related Solutions

MATLAB: Rgb2gray error

Convert to gray scale:

Filelist= dir('Clipboard*.png');
numberOfFiles = length(Filelist);
for k = 1 : numberOfFiles % Don't use i (the imaginary variable).
    thisImage = imread(Filelist(k).name);
    [rows, columns, numberOfColorChannels] = size(thisImage);
    if k == 1
        % Instantiate I with the size of the first image.
        I = zeros(rows, columns, numberOfFiles, class(thisImage));
    end
    if numberOfColorChannels > 1
        % It's color.  Need to convert to gray scale before putting it into the 3D image as the k'th slice.
        I(:,:, k) = rgb2gray(thisImage);
    else
        % Already grayscale.  No need to convert.  Just put in directly as the k'th slice.
        I(:,:, k) = thisImage;
    end
end

MATLAB: Color array to grayscale, images

% Read the image
img1 = imread('photo1.jpg');
% Convert it to double
img1Double = im2double(img1);
% Convert from RGB to grayscale
img1Gray = rgb2gray(img1);
% Display the results
figure
imshowpair(img1, img1Gray, 'montage')

You can do the same for 'photo2.jpg'

Best Answer

Related Solutions

MATLAB: Rgb2gray error

MATLAB: Color array to grayscale, images

Related Question