I'm not sure, that margins are also multiple of 6 in 0.19. Extra effort is needed to analyze (source inspection, may be debugger session), so I won’t do it,
If not, xtrans[][] is for visible area, xtrans_abs[][] is for entire sensor (make sure you use LibRaw-provided margins).
0 is 'channel #0', 1 is 'channel #1', etc. Index to name mapping is in imgdata.idata.cdesc[] string.
I'm not sure, that margins are also multiple of 6 in 0.19. Extra effort is needed to analyze (source inspection, may be debugger session), so I won’t do it,
If not, xtrans[][] is for visible area, xtrans_abs[][] is for entire sensor (make sure you use LibRaw-provided margins).
0 is 'channel #0', 1 is 'channel #1', etc. Index to name mapping is in imgdata.idata.cdesc[] string.