Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages


home | help
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.

       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

       --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 function codes 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.

       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. On *NIX systems, the	direc-
	      tories are separated by a	colon (`:'), under OS/2, they are sep-
	      arated  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 /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/local/etc/sane.d be-
	      ing 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(1) is a command line	front-
	      end that supports	multi-page scans.  It has been	used  success-
	      fully  with  this	backend.  The SANE frontend xsane(1) is	an im-
	      proved 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  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(1)
	      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(1) 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.

       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),	xsane(1)

       The sane-bh backend was written by Tom Martone, based on	 the  sane-ri-
       coh(5)  backend	by  Feico  W.  Dillema and the bnhscan program by Sean
       Reifschneider of ltd.	Some 8000 enhancements added  by  Mark

				  10 Jul 2008			    sane-bh(5)


Want to link to this manual page? Use this URL:

home | help