How to delete every second pixel of each row from a photo?

Hi everyone,

I need to write a program which will take a photo as a input and then I want to delete every second pixel of each row from a photo.

How can i do this? Thank you very much.

regards

ferdows

Answer 1

[Image Analyst]

Try this for a gray scale image:

grayImage= grayImage(:, 1:2:end);

Or, if it's an RGB image:

rgbImage = rgbImage(:, 1:2:end, :);

You can assign it to a different image if you don't want to change your input image.

grayImage2 = grayImage(:, 1:2:end);
rgbImage2 = rgbImage(:, 1:2:end, :);

You can also start at column 2 if you want but using 2:2:end instead of 1:2:end.

[Image Analyst]

It's really easy to just do in a single line like I suggested above, but if really you need it as a function....

function outputImage = SubSampleImage(inputImage)
  [rows, columns, numberOfColorChannels] = size(inputImage);
  if numberOfColorChannels == 1
    outputImage = inputImage(:, 1:2:end);
  else
    outputImage = inputImage(:, 1:2:end, :);
  end

though when you call this function you'll still have a single line of code like you'd have if you used my first suggestion and didn't use a function, because you need to call the function. My function is robust enough to handle both gray scale and multispectral/RGB images.

Answer 2

[Rushikesh Tade]

Try following code:

function output_image=alternate_rows(input_image)  
  output_image=[];

    for i=1:size(input_image,1)

       output_image=[output_image input_image(i,1:2:size(input_image,2))]

    end

Answer 3

[Adam]

nCols = size( photo, 2 );
photo = photo( :, 1:2:nCols );