if i break a RGB image into lab image and then for each channel if i have done haftoning using BGA algorithm and filter and minimized its error.then i how to combine 3 channel to see the whole image to compare it with its original image????

i got halftone channel image say I_a_bl_ht for l channel I_b_bl_ht for a channel and I_c_bl_ht for b channel so how can i combine three and able to see the whole image??