Decomposition of EEG signal using wavelet packet transform?

Hi all, I'm having a bit of a trouble breaking down an EEG signal into these bands using wavelet packet decomposition. I tried dwptand for inverse idwpt. But it decreasing the sampling points. I need to recostruct after decomposition. That when I don't understand. Should I use modwt?

delta(0-4Hz)
theta(4-8Hz) 
alpha(8-12)
beta(12-24)

Here is the 10 channel EEG data. Can anyone help me with band separation using wavelet packet decomposition? the sampling frequency is 128 Hz. And each channel has 640 data points which means 640/128=5 sec data.

Thank you all.