Two-Dimensional Wavelet Analysis Using the Command Line

I have a RGB image and I wanna implement 2D wavelet on it without using wavelet toolbox and just using command line:

• X = imread('hslc_L8.jpg');
• [cA1,cH1,cV1,cD1] = dwt2(X,'bior3.7');
• A1 = upcoef2('a',cA1,'bior3.7',1);
• H1 = upcoef2('h',cH1,'bior3.7',1);
• V1 = upcoef2('v',cV1,'bior3.7',1);
• D1 = upcoef2('d',cD1,'bior3.7',1);
• sx = size(X);
• A1 = idwt2(cA1,[],[],[],'bior3.7',sx);
• H1 = idwt2([],cH1,[],[],'bior3.7',sx);
• V1 = idwt2([],[],cV1,[],'bior3.7',sx);
• D1 = idwt2([],[],[],cD1,'bior3.7',sx);
• .....
• subplot(2,5,2);image(wcodemat(A1,192));title('Approximation A1')
• axis off

In the highlighted line this error pops up: Error using image TrueColor CData contains element out of range 0.0 <= value <= 1.0

What should I do????