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GOCR(1) 			  User's Manual 			 GOCR(1)

NAME
     gocr - command line text recognition tool

SYNOPSIS
     gocr [OPTION] [-i] pnm-file

DESCRIPTION
     gocr  is an optical character recognition program that can be used from the
     command line.  It takes input in PNM, PGM, PBM, PPM,  or  PCX  format,  and
     writes  recognized  text  to stdout.  If the pnm file is a single dash, PNM
     data is read from stdin.  If gzip, bzip2 and netpbm-progs are installed and
     your system supports popen(3) also pnm.gz, pnm.bz2, png, jpg,  jpeg,  tiff,
     gif,  bmp, ps (only single pages) and eps are supported as input files (not
     as input stream), where pnm can be replaced by one of ppm, pgm and pbm.

OPTIONS
     -h     show usage information

     -V     show version information

     -i file
	    read input from file (or stdin if file is a single dash)

     -o file
	    send output to file instead of stdout

     -e file
	    send errors to file instead of stderr or to stdout if file is a dash

     -x file
	    progress output to file (file can be a file name, a fifo name  or  a
	    file descriptor 1...255), this is useful for GUI developpers to show
	    the OCR progress, the file descriptor argument is only available, if
	    compiled with __USE_POSIX defined

     -p path
	    database  path,  a	final  slash must be included, default is ./db/,
	    this path will be populated with images of learned characters

     -f format
	    output format of the recognized text (ISO8859_1 TeX  HTML  XML  UTF8
	    ASCII), XML will also output position and probability data

     -l level
	    set  grey  level  to  level (0<160<=255, default: 0 for autodetect),
	    darker pixels belong to characters, brighter pixels are  interpreted
	    as background of the input image

     -d size
	    set  dust size in pixels (clusters smaller than this are removed), 0
	    means no clusters are removed, the default is -1 for auto detection

     -s num
	    set spacewidth between words in units of dots (default:  0	for  au-
	    todetect),	wider  widths are interpreted as word spaces, smaller as
	    character spaces

     -v verbosity
	    be verbose to stderr; verbosity is a bitfield

     -c string
	    only verbose output of characters from string to stderr, more output
	    is generated for all characters within the	string,  the  underscore
	    stands  for  unknown  chars, this function is usefull to limit debug
	    information to the necessary one

     -C string
	    only recognise characters from string, this is a filter function  in
	    cases  where  the interest is only to a part of the character alpha-
	    bet, you can use 0-9 or a-z to specify ranges, use -- to detect  the
	    minus sign

     -a certainty
	    set  value for certainty of recognition (0..100; default: 95), char-
	    acters with a higher certainty are accepted, characters with a lower
	    certainty are treated as unknown (not recognized); set  higher  val-
	    ues, if you want to have only more certain recognized characters

     -u string
	    output this string for every unrecognized character (default is "_")

     -m mode
	    set oprational mode; mode is a bitfield (default: 0)

     -n bool
	    if	bool  is non-zero, only recognise numbers (this is now obsolete,
	    use -C "0123456789")

     The verbosity is specified as a bitfield:

     1	       print more info

     2	       list shapes of boxes (see -c) to stderr

     4	       list pattern of boxes (see -c) to stderr

     8	       print pattern after recognition for debugging

     16        print debug information about recognition of lines to stderr

     32        create outXX.png with boxes and lines marked on each general OCR-
	       step

     The operation modes are:

     2	       use database to recognize characters which are not recognized  by
	       other algorithms, (early development)

     4	       switching on layout analysis or zoning (development)

     8	       don't compare unrecognized characters to recognized one

     16        don't try to divide overlapping characters to two or three single
	       characters

     32        don't do context correction

     64        character  packing, before recognition starts, similar characters
	       are searched and only one of this characters will be send to  the
	       recognition engine (development)

     130       extend database, prompts user for unidentified characters and ex-
	       tends the database with users answer (128+2, early development)

     256       switch  off  the recognition engine (makes sense together with -m
	       2)

AUTHOR
     Joerg  Schulenburg  (see  http://www-e.uni-magdeburg.de/jschulen/ocr/   for
     EMAIL)
     First version of man page by Tim Waugh <twaugh@redhat.com>

VERSION INFORMATION
     This man page documents gocr, version 0.52.

REPORTING BUGS
     Report bugs to Joerg Schulenburg

SEE ALSO
     More details can be found at /usr/share/doc/gocr-X.XX/gocr.html.  Also read
     /usr/share/doc/gocr-X.XX/README to learn, how to improve results.

EXAMPLES
     gocr -v 33 text1.pbm
	    output  verbose  information, out30.png is created to see details of
	    recognition process

     gocr -v 7 -c _YV text1.pbm
	    verbose output for unknown chars and chars Y and V

     djpeg -pnm -gray text.jpg | gocr -
	    convert a jpeg file to pnm format and input via pipe

Linux				   20 Sep 2018				 GOCR(1)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=gocr&sektion=1&manpath=FreeBSD+Ports+15.1.quarterly>

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