I have a standard jpeg image, which I use within some commercial software to colorize other data (by mapping the image's color onto the data). Then I export the colored data from this software to an XYRGB ascii file, i.e. I store the data information in the first two columns of each row and then the three RGB colors in the last three columns.
Since I need to convert the color to CIELab or CIELuv, it seems I need to know which exact colorspace (RGB, sRGB, gamma, whitepoint - you name it) my RGB values are in. But the question is: How can I find out? Or could I just assume a certain profile being a good approximation?
(Remark: The company of the commercial software I used was not able to tell me any specifics...)