Hi Alex,

Thank you for the quick reply! Appreciate it!

I understand there are several steps if dcraw_process () is called. Since I am interested in getting the image data that is very close to the "demosaic RAW", I manually set some parameter to "avoid" unnecessary processing on the RGB code values. For example, I did the following:

-----------------------------------------
use_camera_matrix = 0;
highlight = 0;
use_camera_wb = 0;
output_color = 0;
gamm[0] = 1.0; gamm[1] = 1.0;
no_auto_bright = 1;
user_mul[0] = 1.0; user_mul[1] = 1.0; user_mul[2] = 1.0;
-----------------------------------------

If the setting sounds reasonable, when I add "half_size=1", the converted image looks like a channel is missing.

Thanks a lot!