sbpassemble reads a series of ICP-format image files and assembles them into a multi-level subband pyramid subband_pyramid (SBP format with L >= 1 in the header). It is assumed that the low-resolution baseband image comes first in the list icpfiles; the subsequent high-resolution subbands are input in order horizontal, vertical, and diagonal, starting at level L of the pyramid (low resolution, low frequency) and ending with level 1 (high resolution, high frequency).
The number of icpfiles must be exact--for a subband pyramid of L levels, there must be (L*3+1) icpfiles given.