Hi Olaf, sorry for not being clear about my suggestion. I am aware that various options exist for the user to select hardware gamma correction, and that software gamma correction is discouraged.
However, this is exactly the problem. Without software gamma correction, a frontend is unable to request a certain gamma correction, and cannot choose a gamma correction value suitable for the current operating system, and the current device, or user preferences transferred from a different device. So my suggestion would be to prescribe a software gamma correction option with the values 0 to 2.2, 0 standing for "off". Alternatively, a read-only option "HardwareGamma" could provide the frontend with enough information to implement software gamma correction by itself. Regards, Juergen > Am 13.10.2020 um 10:45 schrieb Olaf Meeuwissen <[email protected]>: > > Hi Jürgen, > > Jürgen Mellinger writes: > >> Specifying a gamma value for acquired scan data would greatly add to >> usability as well. > > That's already in the version 2 draft. See > > https://sane-project.gitlab.io/standard/draft-2/api.html#gamma-table-options > https://sane-project.gitlab.io/standard/draft-2/api.html#analog-gamma > > Both are for device-side gamma support and the standard discourages > emulation in the backend of the former and forbids for the latter. > > Hope this helps, > -- > Olaf Meeuwissen, LPIC-2 FSF Associate Member since 2004-01-27 > GnuPG key: F84A2DD9/B3C0 2F47 EA19 64F4 9F13 F43E B8A4 A88A F84A 2DD9 > Support Free Software https://my.fsf.org/donate > Join the Free Software Foundation https://my.fsf.org/join
