[sane-devel] Option not active

[stef]

On Wed, Aug 13, 2003 at 05:03:47PM +0530, aneesh m raj wrote:
> Hi all,
> Im trying to set the red-gamma-table option for a UMAX 2000p scanner but SANE_OPTION_IS_ACTIVE return false,I have changed the mode to Color. what will be the problem.
> Thanks
> Aneesh

	As given by 'scanimage --help -d umax_pp:/dev/parport0'  :

Options specific to device `umax_pp:/dev/parport0':
  Scan mode:
    -- 
        
    --mode Lineart|Grayscale|Color [Grayscale]
        Selects the scan mode (e.g., lineart,monochrome, or color).
    --resolution 75..1200dpi [75]
        Sets the resolution of the scanned image.
    --preview[=(yes|no)] [no]
        Request a preview-quality scan.
    --preview-in-gray[=(yes|no)] [no]
        Request that all previews are done in monochrome mode.  On a
        three-pass scanner this cuts down the number of passes to one and on a
        one-pass scanner, it reduces the memory requirements and scan-time of
        the preview.
  Geometry:
    -- 
        
    -l 0..5100pel [0]
        Top-left x position of scan area.
    -t 0..7000pel [0]
        Top-left y position of scan area.
    -x 0..5100pel [5100]
        Width of scan-area.
    -y 0..7000pel [7000]
        Height of scan-area.
  Enhancement:
    -- 
        
    --lamp-control[=(yes|no)] [yes]
        Sets lamp on/off
    --UTA-control[=(yes|no)] [inactive]
        Sets UTA on/off
    --custom-gamma[=(yes|no)] [inactive]
        Determines whether a builtin or a custom gamma-table should be used.
    --gamma-table 0..255,...
        Gamma-correction table.  In color mode this option equally affects the
        red, green, and blue channels simultaneously (i.e., it is an intensity
        gamma table).
    --red-gamma-table 0..255,...
        Gamma-correction table for the red band.
    --green-gamma-table 0..255,...
        Gamma-correction table for the green band.
    --blue-gamma-table 0..255,...
        Gamma-correction table for the blue band.
    --manual-channel-brightness[=(yes|no)] [no]
        Color channels brightness settings
    --gray-brightness 0..15 [inactive]
        Sets gray channel brightness
    --red-brightness 0..15 [inactive]
        Sets red channel brightness
    --green-brightness 0..15 [inactive]
        Sets green channel brightness
    --blue-brightness 0..15 [inactive]
        Sets blue channel brightness
    --manual-contrast[=(yes|no)] [no]
        Color channels contrast settings
    --gray-contrast 0..15 [inactive]
        Sets gray channel contrast
    --red-contrast 0..15 [inactive]
        Sets red channel contrast
    --green-contrast 0..15 [inactive]
        Sets green channel contrast
    --blue-contrast 0..15 [inactive]
        Sets blue channel contrast


	So --custom-gamma must be set to yes before setting gamma table.

Regards,
	Stef