Right, sorry Alex, I forgot those steps that you explained them in the documentation of the C++ API.
Nonetheless I don't understand what is "imgdata.colordata.black" , it is defined in the documentation as just "unsigned black", but "unsigned what??" is that another way to say void*? (a pointer to any type?). Or is "black" an actual structure? So, i'm confused with all the "unsigned" not followed by a usual type (like in "unsigned int") but by "black" , "maximum" etc...
I only understand that calling subtract_black() will subtrack black level "values" and black level "data", yet I don't understand the difference between "black level values" and "black level data", as written in http://www.libraw.org/docs/API-CXX-eng.html#subtract_black.
Could you shed some light on this "dark-ness"... ?
Indeed, my app is for astrophotography, we do take so-called stacks of "dark images" and subtract them from the raw images. I wonder if using black, cblack... would be redundant, or even worse, inconsistent with using calibration dark images taken ourselves. Understanding this dark, cblack, levels, data, ... will help to decide what I shall (not) use.
Right, sorry Alex, I forgot those steps that you explained them in the documentation of the C++ API.
Nonetheless I don't understand what is "imgdata.colordata.black" , it is defined in the documentation as just "unsigned black", but "unsigned what??" is that another way to say void*? (a pointer to any type?). Or is "black" an actual structure? So, i'm confused with all the "unsigned" not followed by a usual type (like in "unsigned int") but by "black" , "maximum" etc...
I only understand that calling subtract_black() will subtrack black level "values" and black level "data", yet I don't understand the difference between "black level values" and "black level data", as written in http://www.libraw.org/docs/API-CXX-eng.html#subtract_black.
Could you shed some light on this "dark-ness"... ?
Indeed, my app is for astrophotography, we do take so-called stacks of "dark images" and subtract them from the raw images. I wonder if using black, cblack... would be redundant, or even worse, inconsistent with using calibration dark images taken ourselves. Understanding this dark, cblack, levels, data, ... will help to decide what I shall (not) use.
And merry christmas to you!! (it's Dec, 25th...)