sane-dmc.5

sane-dmc(5)              SANE Scanner Access Now Easy              sane-dmc(5)

NAME

       sane-dmc - SANE backend for the Polaroid Digital Microscope Camera

DESCRIPTION

       The  sane-dmc library implements a SANE (Scanner Access Now Easy) back-
       end that provides access to the Polaroid Digital Microscope Camera.

DEVICE NAMES

       This backend expects device names of the form:

              special

       Where special is the UNIX path-name for the special device that  corre-
       sponds  to the scanner.  The special device name must be a generic SCSI
       device or a symlink to such a device.  Under Linux, such a device  name
       could be /dev/sga or /dev/sge, for example.

IMAGING MODES

       The  Polaroid DMC supports a number of imaging modes.  This driver sup-
       ports five of the imaging modes:

       Full Frame
              This mode corresponds to the 801-by-600 pixel  full-color  full-
              frame image.

       Viewfinder
              This   mode  corresponds  to  the  270-by-201  pixel  grey-scale
              viewfinder image.  This image is acquired very quickly.

       Raw    This mode corresponds to the 1599-by-600 pixel "raw" image  from
              the CCD.  It is grey-scale, with pixels alternating horizontally
              between red, green and blue stripes.  The pixels  are  twice  as
              high as they are wide, so the image is distorted.

       Thumbnail
              This mode corresponds to the 80-by-60 pixel full-color thumbnail
              image.

       Super Resolution
              This image is a 1599-by-1200 pixel full-color image  constructed
              by  filtering  and interpolating the "raw" image.  The filtering
              and interpolation is done in software,  so  this  mode  is  very
              slow.   Also,  this mode places restrictions on how the image is
              read which means that the "preview" mode of xscanimage does  not
              work  in Super Resolution mode.  (xcam and the non-preview modes
              of scanimage and xscanimage work fine, however.)

OTHER SETTINGS

       ASA Setting
              This setting adjusts the camera's sensitivity.  You  can  choose
              one of 25, 50, or 100 "equivalent" ASA.

       Shutter Speed
              You can select a shutter speed from 8 to 1000 milliseconds.  The
              shutter speed is quantized in units of 32 microseconds.

       White Balance
              You can choose one of "Daylight",  "Incandescent"  or  "Fluores-
              cent"  white balances.  This setting more-or-less corresponds to
              the "Color Temperature" settings on Polaroid's Windows  and  Mac
              software.

CONFIGURATION

       The contents of the dmc.conf file is a list of device names that corre-
       spond to DMC scanners.  Empty lines and lines starting with a hash mark
       (#) are ignored.  A sample configuration file is shown below:

              /dev/scanner
              # this is a comment
              /dev/sge

FILES

       /usr/local/etc/sane.d/dmc.conf
              The   backend   configuration  file  (see  also  description  of
              SANE_CONFIG_DIR below).

       /usr/local/lib/sane/libsane-dmc.a
              The static library implementing this backend.

       /usr/local/lib/sane/libsane-dmc.so
              The shared library implementing this backend (present on systems
              that support dynamic loading).

ENVIRONMENT

       SANE_CONFIG_DIR
              This environment variable specifies the list of directories that
              may contain the configuration file.  Under UNIX, the directories
              are  separated  by a colon (`:'), under OS/2, they are separated
              by a semi-colon (`;').  If this variable is not set, the config-
              uration  file is searched in two default directories: first, the
              current    working    directory    (".")     and     then     in
              /usr/local/etc/sane.d.  If the value of the environment variable
              ends with the directory separator character,  then  the  default
              directories are searched after the explicitly specified directo-
              ries.  For example, setting  SANE_CONFIG_DIR  to  "/tmp/config:"
              would    result    in   directories   "tmp/config",   ".",   and
              "/usr/local/etc/sane.d" being searched (in this order).

       SANE_DEBUG_DMC
              If the library was compiled with  debug  support  enabled,  this
              environment  variable controls the debug level for this backend.
              E.g., a value of 128 requests all debug output  to  be  printed.
              Smaller levels reduce verbosity.

BUGS

       In  the  "Full  Frame" and "Raw" modes, images must be read in units of
       entire lines.  The driver performs no buffering in these modes; if  you
       ask  sane_read to read a non-integral number of lines, it may read less
       than you ask for.  If you ask sane_read to  read  less  than  a  single
       line, it returns SANE_STATUS_INVAL.

       In  the  "Super  Resolution"  mode, images must be read in units of two
       lines (3198 pixels or 9594 bytes.)  If you try to read  less  than  two
       lines,  you  get  SANE_STATUS_INVAL.  The Super Resolution mode is very
       slow.

       In the "Viewfinder" and "Thumbnail" modes, the  entire  image  must  be
       read in one SCSI transfer.  In this case, the driver performs buffering
       and you can read the image in as small an increment as you like.

SEE ALSO

       sane(7), sane-scsi(5)

AUTHOR

       David F. Skoll

       The backend is derived from sane-hp by David Mosberger

sane-backends 1.0.18              13 May 1998                      sane-dmc(5)