h = daubcqf(6); load lena;
noisyLena = lena + 25 * randn(size(lena));
figure; colormap(gray); imagesc(lena); title('Original Image');
figure; colormap(gray); imagesc(noisyLena); title('Noisy Image');
Denoise lena with the default method based on the DWT
[denoisedLena,xn,opt1] = denoise(noisyLena,h);
figure; colormap(gray); imagesc(denoisedLena); title('denoised Image');