Reconstruct single branch from 2-D wavelet coefficients

`X = wrcoef2(`

* 'type'*,C,S,

`'wname'`

X = wrcoef2(

`'type'`

X = wrcoef2(

`'type'`

`'wname'`

X = wrcoef2(

`'type'`

`wrcoef2`

is a two-dimensional
wavelet analysis function. `wrcoef2`

reconstructs
the coefficients of an image.

`X = wrcoef2(`

computes
the matrix of reconstructed coefficients of level * 'type'*,C,S,

`'wname'`

`N`

,
based on the wavelet decomposition structure `[C,S]`

(see `wavedec2`

for more information). * 'wname'* is a string containing the
name of the wavelet (see

`wfilters`

for
more information). If `'type'`

```
=
'a'
```

, approximation coefficients are reconstructed; otherwise
if `'type'`

`= 'h'`

(`'v'`

or `'d'`

,
respectively), horizontal (vertical or diagonal, respectively) detail
coefficients are reconstructed.Level `N`

must be an integer such that `0`

≤ `N`

≤ `size(S,1)-2`

if `'type'`

```
=
'a'
```

and such that `1`

≤` N `

≤` size(S,1)-2`

if `'type'`

```
=
'h'
```

, `'v'`

, or `'d'`

.

Instead of giving the wavelet name, you can give the filters.

For `X = wrcoef2(`

, * 'type'*,C,S,Lo_R,Hi_R,N)

`Lo_R`

is
the reconstruction low-pass filter and `Hi_R`

is
the reconstruction high-pass filter. `X = wrcoef2(`

or * 'type'*,C,S,

`'wname'`

```
X
= wrcoef2(
````'type'`

,C,S,Lo_R,Hi_R)

reconstruct
coefficients of maximum level `N = size(S,1)-2`

.% The current extension mode is zero-padding (see dwtmode). % Load an image. load woman; % X contains the loaded image. % Perform decomposition at level 2 % of X using sym5. [c,s] = wavedec2(X,2,'sym5'); % Reconstruct approximations at % levels 1 and 2, from the wavelet % decomposition structure [c,s]. a1 = wrcoef2('a',c,s,'sym5',1); a2 = wrcoef2('a',c,s,'sym5',2); % Reconstruct details at level 2, % from the wavelet decomposition % structure [c,s]. % 'h' is for horizontal, % 'v' is for vertical, % 'd' is for diagonal. hd2 = wrcoef2('h',c,s,'sym5',2); vd2 = wrcoef2('v',c,s,'sym5',2); dd2 = wrcoef2('d',c,s,'sym5',2); % All these images are of same size sX. sX = size(X) sX = 256 256 sa1 = size(a1) sa1 = 256 256 shd2 = size(hd2) shd2 = 256 256

Was this topic helpful?