sane-bh.5



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


NAME

       sane-bh  -  SANE  backend  for  Bell+Howell Copiscan II series document
       scanners


DESCRIPTION

       The sane-bh library implements a SANE (Scanner Access Now Easy) backend
       that  provides  access to Bell+Howell Copiscan II series document scan‐
       ners.  The Copiscan II 6338 has been the  primary  scanner  model  used
       during development and testing, but since the programming interface for
       the entire series is consistent the backend should work for the follow‐
       ing scanner models.

              COPISCAN II 6338 Duplex Scanner with ACE
              COPISCAN II 2135 Simplex Scanner
              COPISCAN II 2137(A) Simplex Scanner (with ACE)
              COPISCAN II 2138A Simplex Scanner with ACE
              COPISCAN II 3238 Simplex Scanner
              COPISCAN II 3338(A) Simplex Scanner (with ACE)

       If  you  have  a  Bell+Howell scanner and are able to test it with this
       backend, please  contact  sane-devel@alioth-lists.debian.net  with  the
       model    number    and    testing    results.    Have    a    look   at
       http://www.sane-project.org/mailing-lists.html concerning  subscription
       to sane-devel. Additionally, the author is curious as to the likelihood
       of using this backend with the newer 4000 and 8000 series scanners.  If
       you have such a beast, please let me know.

       The  Bell+Howell  Copiscan II series document scanners are high volume,
       high throughput scanners designed for document  scanning  applications.
       As  such, they are lineart/grayscale scanners supporting a fixed number
       of fairly low resolutions (e.g. 200/240/300dpi).  However, they do have
       a number of interesting and useful features suited to needs of document
       imaging applications.  This backend attempts  to  support  as  many  of
       these features as possible.

       The  main  technical reference used in writing this backend is the Bell
       and Howell Copiscan II Remote SCSI Controller (RSC) OEM Technical  Man
       ual  Version 1.5.  The Linux SCSI programming HOWTO, the SANE API docu‐
       mentation, and SANE source code were also extremely valuable resources.

       The latest backend release, additional information  and  helpful  hints
       are available from the backend homepage:
              http://www.martoneconsulting.com/sane-bh.html


DEVICE NAMES

       This backend expects device names of the form:

              special

       Where  special is the path-name for the special device that corresponds
       to a SCSI scanner. For SCSI scanners, the special device name must be a
       generic SCSI device or a symlink to such a device.  Under Linux, such a
       device name takes a format such as /dev/sga or /dev/sg0,  for  example.
       See sane-scsi(5) for details.


CONFIGURATION

       The  contents of the bh.conf file is a list of device names that corre‐
       spond to Bell+Howell scanners.  See sane-scsi(5)  on  details  of  what
       constitutes  a  valid device name.  Additionally, options can be speci‐
       fied; these lines  begin  with  the  word  "option".   Each  option  is
       described  in detail below.  Empty lines and lines starting with a hash
       mark (#) are ignored.


OPTIONS

       The following options can be specified in the bh.conf file.

       disable-optional-frames
              This option prevents  the  backend  from  sending  any  optional
              frames.   This  option may be useful when dealing with frontends
              which do not support these optional frames.  When this option is
              in  effect,  the  data  is sent in a SANE_FRAME_GRAY frame.  The
              optional frames  sent  by  this  backend  are:  SANE_FRAME_G31D,
              SANE_FRAME_G32D,  SANE_FRAME_G42D  and  SANE_FRAME_TEXT.   These
              frames are  generated  based  on  the  compression  and  barcode
              options.  These frames are never sent in preview mode.

       fake-inquiry
              This  option  is  used for debugging purposes and its use is not
              encouraged.  Essentially, it allows the backend to initialize in
              the  absence  of  a scanner.  This is useful for development and
              not much else.  This option must be  specified  earlier  in  the
              configuration file than the devices which are to be "faked".


FILES

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

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

       /usr/local/lib/sane/libsane-bh.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_BH
              If the library was compiled with  debug  support  enabled,  this
              environment  variable controls the debug level for this backend.
              E.g., a value of 255 requests all debug output  to  be  printed.
              Smaller levels reduce verbosity.


SUPPORTED FEATURES

       ADF support
              With  document scanners, automatic document feeder (ADF) support
              is a key feature.  The backend supports the ADF by  default  and
              returns  SANE_STATUS_NO_DOCS  when the out-of-paper condition is
              detected.  The SANE frontend scanadf is a command line  frontend
              that  supports  multi-page scans.  It has been used successfully
              with this backend.  The SANE frontend xsane is an  improved  GUI
              frontend  by  Oliver  Rauch.   Support  for  multi-page scans is
              included in xsane version 0.35 and above.

       Duplex scanning
              Some models, such as the COPISCAN II 6338, support duplex  scan‐
              ning.   That  is,  they scan both sides of the document during a
              single pass through the scanner (the scanner has  two  cameras).
              This   backend  supports  duplex  scanning  (with  the  --duplex
              option).  The front and back page images are delivered  consecu‐
              tively as if they were separately scanned pages.

       Hardware compression
              The  scanner  is  capable  of  compressing the data into several
              industry standard formats (CCITT G3,  CCITT  G3-2D,  CCITT  G4).
              This  results  in  increased  performance as less data is passed
              from the scanner to the host over the  SCSI  bus.   The  backend
              supports  these  compression  formats  via  the  --g31d, --g32d,
              --g42d options,  respectively.   Many  SANE  frontends  are  not
              equipped to deal with these formats, however.  The SANE frontend
              scanadf supports these optional frame formats.   The  compressed
              image  data  is  written directly to a file and can then be pro‐
              cessed by a scan-script using the --scan-script  option.   Exam‐
              ples of this are given on the scanadf homepage.

       Automatic Border Detection
              The  scanner  can automatically detect the paper size and adjust
              the scanning window geometry appropriately.   The  backend  sup‐
              ports  this  useful feature with the --autoborder option.  It is
              enabled by default.

       Batch Mode Scanning
              The batch scan mode allows for maximum throughput.  The Set Win‐
              dow parameters must remain constant during the entire batch.

       Icon Generation
              The  Icon function generates a thumbnail of the full page image,
              that can be transferred as if it were  a  separate  page.   This
              allows  the  host  to quickly display a thumbnail representation
              during the scanning operation.  Perhaps this would  be  a  great
              way  of  implementing a preview scan, but since a normal scan is
              so quick, it might not be worth the trouble.

       Multiple Sections
              Multiple sections (scanning sub-windows) can be defined for  the
              front  and  back pages.  Each section can have different charac‐
              teristics  (e.g.  geometry,  compression).   The  sections   are
              returned  as  if they were separately scanned images.  Addition‐
              ally sections can be used to greatly enhance  the  accuracy  and
              efficiency of the barcode/patchcode decoding process by limiting
              the search area to a small subset of the page.  Most Copiscan II
              series scanners support up to 8 user-defined sections.

       Support Barcode/Patchcode Decoding
              The  RSC unit can recognize Bar and Patch Codes of various types
              embedded in the scanned image.  The codes are  decoded  and  the
              data  is  returned to the frontend as a text frame.  The text is
              encoded in xml and contains a great deal  of  information  about
              the  decoded  data  such as the location where it was found, its
              orientation, and the time it took to find.  Further  information
              on the content of this text frame as well as some barcode decod‐
              ing examples can be found on the backend homepage.


LIMITATIONS

       Decoding a single barcode type per scan
              The RSC unit can search for up to six different barcode types at
              a  time.   While  the  code generally supports this as well, the
              --barcode-search-bar option only allows the user  to  specify  a
              single  barcode  type.   Perhaps  another  option which allows a
              comma separated list of barcode type codes  could  be  added  to
              address this.

       Scanning a fixed number of pages in batch mode
              The  separation  of  front  and  back  end functionality in SANE
              presents a problem in supporting the 'cancel batch'  functional‐
              ity in the scanner.  In batch mode, the scanner is always a page
              ahead of the host.  The host, knowing ahead of time  which  page
              will  be the last, can cancel batch mode prior to initiating the
              last scan command.  Currently, there is no  mechanism  available
              for  the  frontend  to  pass  this knowledge to the backend.  If
              batch mode is enabled and the --end-count terminates  a  scanadf
              session,  an  extra page will be pulled through the scanner, but
              is neither read nor delivered to the frontend.  The issue can be
              avoided by specifying --batch=no when scanning a fixed number of
              pages.

       Revision 1.2 Patch detector
              There is an enhanced patchcode detection algorithm available  in
              the  RSC  with  revision  1.2  or higher that is faster and more
              reliable than the standard Bar/Patch code decoder.  This is  not
              currently supported.


OPTIONS

       Scan Mode Options:

       --preview[=(yes|no)] [no]
              Request  a  preview-quality  scan.   When  preview is set to yes
              image compression is disabled and the image is  delivered  in  a
              SANE_FRAME_GRAY frame.

       --mode lineart|halftone [lineart]
              Selects the scan mode (e.g., lineart,monochrome, or color).

       --resolution 200|240|300dpi [200]
              Sets  the  resolution  of the scanned image.  Each scanner model
              supports a list of standard resolutions; only these  resolutions
              can be used.

       --compression none|g31d|g32d|g42d [none]
              Sets  the  compression mode of the scanner.  Determines the type
              of data returned from the scanner.  Values are:
              none - uncompressed data - delivered in a SANE_FRAME_GRAY frame
              g31d  -  CCITT  G3  1  dimension   (MH)   -   delivered   in   a
              SANE_FRAME_G31D frame
              g32d  -  CCITT  G3  2  dimensions  (MR,  K=4)  -  delivered in a
              SANE_FRAME_G32D frame
              g42d - CCITT G4 (MMR) - delivered in a SANE_FRAME_G42D frame
              NOTE: The use of g31d, g32d, and g42d compression values  causes
              the  backend to generate optional frame formats which may not be
              supported by all SANE frontends.

       Geometry Options:

       --autoborder[=(yes|no)] [yes]
              Enable/Disable automatic image border detection.  When  enabled,
              the  RSC  unit automatically detects the image area and sets the
              window geometry to match.

       --paper-size Custom|Letter|Legal|A3|A4|A5|A6|B4|B5 [Custom]
              Specify the scan window geometry by specifying the paper size of
              the documents to be scanned.

       --tl-x 0..297.18mm [0]
              Top-left x position of scan area.

       --tl-y 0..431.8mm [0]
              Top-left y position of scan area.

       --br-x 0..297.18mm [297.18]
              Bottom-right x position of scan area.

       --br-y 0..431.8mm [431.8]
              Bottom-right y position of scan area.

       Feeder Options:

       --source Automatic Document Feeder|Manual Feed Tray [Automatic Document
       Feeder]
              Selects the scan source  (such  as  a  document  feeder).   This
              option  is provided to allow multiple image scans with xsane; it
              has no other purpose.

       --batch[=(yes|no)] [no]
              Enable/disable batch mode scanning.  Batch mode allows  scanning
              at  maximum  throughput  by buffering within the RSC unit.  This
              option is recommended when performing multiple pages scans until
              the feeder is emptied.

       --duplex[=(yes|no)] [no]
              Enable duplex (dual-sided) scanning.  The scanner takes an image
              of each side of the document during a single  pass  through  the
              scanner.  The front page is delivered followed by the back page.
              Most options, such as compression, affect  both  the  front  and
              back pages.

       --timeout-adf 0..255 [0]
              Sets  the  timeout  in seconds for the automatic document feeder
              (ADF).  The value 0 specifies the hardware default  value  which
              varies based on the scanner model.

       --timeout-manual 0..255 [0]
              Sets  the  timeout  in  seconds  for semi-automatic feeder.  The
              value 0 specifies the hardware default value which varies  based
              on the scanner model.

       --check-adf[=(yes|no)] [no]
              Check  ADF  Status prior to starting scan using the OBJECT POSI‐
              TION command.  Note that  this  feature  requires  RSC  firmware
              level 1.5 or higher and dip switch 4 must be in the on position.
              NOTE: This option has not been tested extensively and  may  pro‐
              duce undesirable results.

       Enhancement:

       --control-panel[=(yes|no)] [yes]
              Enables the scanner's control panel for selecting image enhance‐
              ment parameters.  When the option is set  to  no  the  following
              options   are  used  to  control  image  enhancement.   See  the
              Bell+Howell scanner users' guide for complete information on ACE
              functionality.

       --ace-function -4..4 [3]
              Specify the Automatic Contrast Enhancement (ACE) Function.

       --ace-sensitivity 0..9 [5]
              Specify the Automatic Contrast Enhancement (ACE) Sensitivity.

       --brightness 0..255 [0]
              Controls  the brightness of the acquired image.  Ignored for ACE
              capable scanners.

       --threshold 0..255 [0]
              Select minimum-brightness to get a white point.  Ignored for ACE
              capable scanners.

       --contrast 0..255 [inactive]
              Controls the contrast of the acquired image.  This option is not
              currently used by the scanner (and perhaps never will be).

       --negative[=(yes|no)] [no]
              Swap black and white, yielding a reverse-video image.

       Icon:

       --icon-width 0..3600pel (in steps of 8) [0]
              Width of icon (thumbnail) image in pixels.

       --icon-length 0..3600pel (in steps of 8) [0]
              Length of icon (thumbnail) image in pixels.

       Barcode Options:

       --barcode-search-bar <see list> [none]
              Specifies the barcode type to search for.  If this option is not
              specified,  or  specified with a value of none, then the barcode
              decoding feature is completely disabled.  The valid barcode type
              are:
              none
              ean-8
              ean-13
              reserved-ean-add
              code39
              code2-5-interleaved
              code2-5-3lines-matrix
              code2-5-3lines-datalogic
              code2-5-5lines-industrial
              patchcode
              codabar
              codabar-with-start-stop
              code39ascii
              code128
              code2-5-5lines-iata

       --barcode-search-count 1..7 [3]
              Number  of  times  that the RSC performs the decoding algorithm.
              Specify the smallest number possible  to  increase  performance.
              If  you are having trouble recognizing barcodes, it is suggested
              that you increase this option to its maximum value (7).

       --barcode-search-mode <see list> [horiz-vert]
              Chooses the orientation of barcodes to be searched.   The  valid
              orientations are:
              horiz-vert
              horizontal
              vertical
              vert-horiz

       --barcode-hmin 0..1660mm [5]
              Sets  the  barcode  minimum height in millimeters (larger values
              increase recognition speed).  Of course the actual  barcodes  in
              the document must be of sufficient size.

       --barcode-search-timeout 20..65535us [10000]
              Sets  the  timeout  for barcode searching in milliseconds.  When
              the timeout expires, the decoder will stop trying to decode bar‐
              codes.

       --section <string> []
              Specifies  a series of image sections.  A section can be used to
              gather a subset image or to provide a  small  area  for  barcode
              decoding.   Each  section  is  specified in the following format
              (units are in millimeters):

       <width>x<height>+<top-left-x>+<top-left-y>[:functioncode...]

       Multiple sections can be specified by separating them with commas.

       For example 76.2x25.4+50.8+0:frontbar identifies an area 3 inches  wide
       and  1  inch  high  with  a  top left corner at the top of the page two
       inches from the left hand edge of the page.  This section will be  used
       for barcode decoding on the front page only.

       For  example  50.8x25.4+25.4+0:frontbar:front:g42d identifies an area 2
       inches wide and 1 inch high with a top left corner at the  top  of  the
       page  one  inch from the left hand edge of the page.  This section will
       be used for barcode decoding on the front page as well as generating an
       image compressed in g42d format.

       Ordinarily  barcodes  are  searched in the entire image.  However, when
       you specify sections all barcode searching is done within the  specific
       sections  identified.   This  can  significantly  speed up the decoding
       process.

       The following functioncodes are available:
              front - generate an image for the front page section
              back - generate an image for the back page section
              frontbar - perform barcode search in front page section
              backbar - perform barcode search in back page section
              frontpatch - perform patchcode search in front page section
              backpatch - perform patchcode search in back page section
              none - use no image compression
              g31d - use Group 3 1 dimension image compression
              g32d - use Group 3 2 dimensions image compression
              g42d - use Group 4 2 dimensions image compression

       If you omit a compression functioncode, the full page compression  set‐
       ting  is used.  If you specify multiple compression functioncodes, only
       the last one is used.

       --barcode-relmax 0..255 [0]
              Specifies the maximum relation from the widest to  the  smallest
              bar.

       --barcode-barmin 0..255 [0]
              Specifies the minimum number of bars in Bar/Patch code.

       --barcode-barmax 0..255 [0]
              Specifies the maximum number of bars in a Bar/Patch code.

       --barcode-contrast 0..6 [3]
              Specifies  the image contrast used in decoding.  Use higher val‐
              ues when there are more white pixels in the code.

       --barcode-patchmode 0..1 [0]
              Controls Patch Code detection.


BUGS

       This is a new backend; detailed bug reports are welcome -- and expected
       ;)

       If  you have found something that you think is a bug, please attempt to
       recreate it with the SANE_DEBUG_BH environment variable set to 255, and
       send   a  report  detailing  the  conditions  surrounding  the  bug  to
       sane-devel@alioth-lists.debian.net.


SEE ALSO

       sane(7), sane-scsi(5), scanimage(1), scanadf(1)


AUTHOR

       The sane-bh backend was written by Tom Martone, based on the sane-ricoh
       backend by Feico W. Dillema and the bnhscan program by Sean Reifschnei‐
       der of tummy.com ltd.  Some 8000 enhancements added by Mark Temple.

                                  10 Jul 2008                       sane-bh(5)

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