halftoning(ordered dithring)

i have a small problem in dithring code when i run the code i get this massage error:

??? Error using ==> gt Matrix dimensions must agree.

i chang the matrix size in repmat(d,128,128) but even of that i get the same message error also i search for alooong time but i could not find the solution for this problem

this is my code: f=imread('2.png'); f2=rgb2gray(f); imshow(f2) d=[0,128;192,64]; r=repmat(d,128,128) f3=f2>r;imshow(f3)

plz i need a small help

Answer 1

[Paulo Silva]

f2 and r don't have the same dimensions for sure, that gt in the error stands for greater than. try this:

isequal(size(f2),size(r))

if the answer is 0 they aren't of equal dimensions

[ram]

yes the answer is zero :(

how can i make matrix 2x2 has the same dimension as my image??

[Paulo Silva]

what's the image size?

[ram]

thx alot for answering my quastion

from where can i know the size of image??

>>... i am begginer in matlab

did u mean this?

cdata 512x512

colormap 265x3

[Paulo Silva]

by size I was referring to the number of pixels, usually it's one array like the cdata one, this should work:

r=repmat(d,256,256) %notice that 256 is 512/2 because d is two lines by two columns

[ram]

thax aloooot it works :)))

r=repmat(d,256,256) %notice that 256 is 512/2 because d is two lines by two columns

did u mean if i use matrix 4x4 like: D2 = [0 128 32 160; 192 64 224 96; 48 176 16 144; 240 112 208 80];

it should be like that: r2 = repmat(D2,128,128);??

[Paulo Silva]

yes

[ram]

thx alot i realy appreciate your help

i spend the whole week looking 4 the solution

u realy save my time

:)