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

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

       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  with  the
       model	number	  and	 testing    results.	Have	a    look   at 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:

       This backend expects device names of the	form:


       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.

       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  de-
       scribed	in  detail  below.  Empty lines	and lines starting with	a hash
       mark (#)	are ignored.

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

	      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 op-
	      tional  frames  sent  by	this  backend  are:   SANE_FRAME_G31D,
	      frames are generated based on the	compression  and  barcode  op-
	      tions.  These frames are never sent in preview mode.

	      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".

	      The   backend   configuration  file  (see	 also  description  of
	      SANE_CONFIG_DIR below).

	      The static library implementing this backend.

	      The shared library implementing this backend (present on systems
	      that support dynamic loading).

	      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/lo-
	      cal/etc/sane.d.	If  the	value of the environment variable ends
	      with the 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 re-
	      sult   in	  directories	"tmp/config",	".",   and   "/usr/lo-
	      cal/etc/sane.d" being searched (in this order).

	      If the library was compiled with debug support enabled, this en-
	      vironment	 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.

       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 in-
	      cluded 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 op-
	      tion).  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 in-
	      dustry 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 op-
	      tions, 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 processed by
	      a	scan-script using the --scan-script option.  Examples 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 al-
	      lows the host to quickly display a thumbnail representation dur-
	      ing 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  re-
	      turned  as if they were separately scanned images.  Additionally
	      sections can be used to greatly enhance the accuracy  and	 effi-
	      ciency of	the barcode/patchcode decoding process by limiting the
	      search area to a small subset of the page.  Most Copiscan	II se-
	      ries 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.

       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 ad-
	      dress 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

       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 re-
	      liable than the standard Bar/Patch code decoder.	 This  is  not
	      currently	supported.

       Scan Mode Options:

       --preview[=(yes|no)] [no]
	      Request  a preview-quality scan.	When preview is	set to yes im-
	      age 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
	      Selects the scan source (such as a document feeder).   This  op-
	      tion  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.


       --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 op-
	      tions  are used to control image enhancement.  See the Bell+How-
	      ell scanner users' guide for complete information	on  ACE	 func-

       --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-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

       --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:

       --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-

       --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 de-
	      coding.	Each  section  is  specified  in  the following	format
	      (units are in millimeters):


       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

       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

       --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.

       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-de-

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

       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	ltd.  Some 8000	enhancements added by Mark Temple.

				  10 Jul 2008			    sane-bh(5)


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