adjust the image quality and color via ISP IPIPE or H3A?

hi,

I want to know how to adjust theimage quality and color, via ISP IPIPE or H3A?the H3A must be required?(I use CMOS sensor),there is a configure value:

struct preview_wb wb_defaults = {
    .ofst_r = 0,
    .ofst_gr = 0,
    .ofst_gb = 0,
    .ofst_b = 0,
    .gain_r = { 1 , 511 },
    .gain_gr = { 1, 511 },
    .gain_gb = { 1, 511 },
    .gain_b = { 1, 511 }

},

Associated Registers:

IPIPE_WB2_OFT_R
IPIPE_WB2_OFT_GR
IPIPE_WB2_OFT_GB
IPIPE_WB2_OFT_B
IPIPE_WB2_WGN_R
IPIPE_WB2_WGN_GR
IPIPE_WB2_WGN_GB
IPIPE_WB2_WGN_B

but I don't know how to configure the value and have a good effect,there aremany combinations,,canyougive me somegood advice?