Extracting decomposed images from wpdec2

Hello,

I am trying to extract decomposed images, such as LL, LH, HL and HH, after using wpdec2.

The result of wpdec2 comes to 'wptree' type and I cannot use this data type for further process.

What I need is only data of a certain node to use as an image to save in JPG, TIFF and so on.

please refer the image attached.

I want to extract and save the data in each node after decomposed by wpdec2.

please help me solve this problem. Thank you.