MATLAB: Decompose an image in YIQ.

yiq

Could someone tell me how i could go about decomposing an RGB image into YIQ? So far i have

I = imread('imagefile') R = I(:,:,1) G = I(:,:,2) B = I(:,:,3)

I also need to display the Y component of YIQ.

Thanks,

Best Answer

The rgb2ntsc that you used in your earlier question is fine. How to display the image was already discussed in http://www.mathworks.com/matlabcentral/answers/321816-how-do-i-correctly-display-the-y-component-of-a-yiq-image#answer_251914 which is waiting for your response.

Related Solutions

MATLAB: Pixel decomposition

What output representation do you want?

You have

B(n,t)={Pn/2^t}

but that is not going to be a single bit except in the special case where Pn == 2^t exactly. Suppose for example that Pn is 3 and t is 1, then B(n,t) would be 3/2^1 which would be 1 1/2 .

Notice too that when defining MSB and LSB you go down to B(n,1) but not to B(n,0) . Thus you are always dividing by at least 2^1 and therefor have no mechanism to get at the bit with the least value (the one that contributes 0 or 2^0 to Pn)

Your notation

Pn=(B(n,t). 2t)

does not make any sense to me. Pn = Sum(B(n,t) * 2^t, t=1..8) would make more sense to me.

If my guess is correct about your desired output representation, then my suspicion is that the desired output can be produced in one expression. On the other hand, I suspect that your talk about B(n,t) is an indication of how you are being directed to code this.

MATLAB: How do i correctly display the Y component of a YIQ image

imshow(Y) is correct. The data you get will be in the range 0 to 1; imshow will detect that, and will automatically add in a grayscale colormap.

You can also use

Y8 = im2uint8(Y);

and now if you

Z = rgb2gray(RGB);

then Y8 and Z should be identical (or nearly so -- identical in the test I did.)

Best Answer

Related Solutions

MATLAB: Pixel decomposition

MATLAB: How do i correctly display the Y component of a YIQ image

Related Question