Michael Chan

Hi Diógenes Diógenes,

Did you run the observeWaveletDecompositionBenchmark_N_levels.m file? As stated in the readme.txt, it is the main executing reference usage file.

For a single decomposition level, set

levelOfDecomposition = 1; % level N = 1

For the inquiries regarding the variables, in image wavelet decomposition, the segments are divided according to the (H)orizontal, (V)ertical, (A)pproximate and (D)iagonal regions.

Usually, the coefficients are represented in the form (in the example of 1 level wavelet decomposition):
        coeff_A1, coeff_H1;
        coeff_V1, coeff_D1;

I hope that helps.

That is true.
The intention though is to make it easier for people to translate by handcoding it to C/ C++ or Java by reducing the use of Matlab toolboxes.

However, I agree with you. I will provide 2 versions later on.

Hi Roy,

Here is an example:

IMG = 'lena.jpg'; % IMG : originalImage
IMG = imread(IMG);
IMG = rgb2gray(IMG);

thicknessOfBorderRimToPad = 5;
valueToPad = 0;

[rowSizeOfOrgImg colSizeOfOrgImg] = size(IMG);
framePadRowSize = rowSizeOfOrgImg + (2*thicknessOfBorderRimToPad);
framePadColSize = colSizeOfOrgImg + (2*thicknessOfBorderRimToPad);
framePad = zeros(framePadRowSize, framePadColSize);

offset = thicknessOfBorderRimToPad;
% position image in frame pad
framePad (offset:(rowSizeOfOrgImg+offset-1), offset:(colSizeOfOrgImg+offset-1)) = IMG;

IMG = framePad;

imshow(IMG, []);

I hope this is clear. You may wish to email me for further inquires, as it is easier to trace the comments in my inbox. I hope it helps.
Thank you.

hi, I am a new user of Matlab, I'm trying to use the function, but is returning the error:

?? Undefined function or variable 'H'.

What H and V represent and how they should be defined?

I'm trying to make a single decomposition level grayscale images. How can I make the decomposition into multiple images at once? Thank you!

That is true.
The intention though is to make it easier for people to translate by handcoding it to C/ C++ or Java by reducing the use of Matlab toolboxes.

However, I agree with you. I will provide 2 versions later on.