I am working on a scientific application where I would like to evaluate luminance in an image, however I am unsure if what I receive from my setup is luminance (Y) or luma (Y'). I use a camera with a TOSH IK CU51 (PAL) control unit which is connected via S-Video to a Canopus ADVC-300 analog to digital converter. The digitized data are streamed to a computer and presented in YUV2 format.
Now the problem: I read into luminance and luma and realized that I do not know if gamma compression is applied somewhere on the way between the camera and the computer, so that really I am getting Y'UV2 instead of YUV2, is there e.g. a definition for a PAL signal to be gamma compressed and for an S-Video signal not to be corrected?
Edit: As there are no answers yet, I think I should be more specific: Is there any flexibility in the PAL or S-Video standard or in how a device is generally expected to work where I would have to take gamma correction into account? A little more background: luminance is proportional to energy per spatial area. If gamma correction were applied then I'd get a somewhat distorted value. If I knew gamma, I could adjust for this.