How can plot pdf histogram or joint histogram of the low frequency curvelet coefficients?

See more:

MatLab

hi every body,

I have the code ,can u help me

x=imread('4.jpg');

x1=rgb2gray(x);

c=fdct_wrapping(x1,0);

img=fdct_wrapping_dispcoef(c);

plz ,How can plot pdf histogram or joint histogram of the low frequency curvelet coefficients?

thanks