Binarizing an image using mean gray value

Hi, I need to binarizing an image according to mean gray value.

The image i'm working in is the Y (Luiminance) Channel of YCbCr color space.

the function im2bw takes grayscale, so I need to convert the image to gray scale( I don't know how to do that because of working on Y channel of YCbCr image) OR getting another procedure.

The Code:

m1 = imread('car1.jpg');

m2 = rgb2ycbcr(m1); sample1=m2(:,:,1);

sample1_mean = mean(mean(sample1))

%Binarizing samples area

BINsample1 = im2bw(sample1, sample1_mean);

I hope if any one can help me.

Thanks in advance,

Eman

Answer 1

[Tallha Akram]

m1 = imread('peppers.png');

m2 = im2double(rgb2ycbcr(m1)); sample1=m2(:,:,1);

sample1_mean = mean(mean(sample1))

%Binarizing samples area

BINsample1 = im2bw(sample1, sample1_mean);

imshow(BINsample1);

[eman]

Thanks Tallha Akram .