sane-dmc(5)               (13 Jul 2008)               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) backend 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 corresponds 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 supports 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

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               work in Super Resolution mode.  (xcam(1) and the non-
               preview modes of scanimage(1) and xscanimage(1) 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 millisec-
               onds.  The shutter speed is quantized in units of 32
               microseconds.

          White Balance
               You can choose one of "Daylight", "Incandescent" or
               "Fluorescent" 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 correspond to DMC scanners.  Empty lines and lines
          starting with a hash mark (#) are ignored.  A sample config-
          uration file is shown below:

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

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

          /usr/lib/x86_64-linux-gnu/sane/libsane-dmc.a
               The static library implementing this backend.

          /usr/lib/x86_64-linux-gnu/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 direc-
               tories 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 configuration file is
               searched in two default directories: first, the current
               working directory (".") and then in /etc/sane.d. If the
               value of the environment variable ends with the

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               directory separator character, then the default direc-
               tories are searched after the explicitly specified
               directories.  For example, setting SANE_CONFIG_DIR to
               "/tmp/config:" would result in directories tmp/config,
               ., and /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(5) by David Mosberger

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