#include <string.h>
#include "allheaders.h"
#include "readbarcode.h"

Macros
#define	DEBUG_CODES 0

Functions
static l_int32	barcodeFindFormat (char *barstr)

static l_int32	barcodeVerifyFormat (char barstr, l_int32 format, l_int32 pvalid, l_int32 *preverse)

static char *	barcodeDecode2of5 (char *barstr, l_int32 debugflag)

static char *	barcodeDecodeI2of5 (char *barstr, l_int32 debugflag)

static char *	barcodeDecode93 (char *barstr, l_int32 debugflag)

static char *	barcodeDecode39 (char *barstr, l_int32 debugflag)

static char *	barcodeDecodeCodabar (char *barstr, l_int32 debugflag)

static char *	barcodeDecodeUpca (char *barstr, l_int32 debugflag)

static char *	barcodeDecodeEan13 (char *barstr, l_int32 first, l_int32 debugflag)

char *	barcodeDispatchDecoder (char *barstr, l_int32 format, l_int32 debugflag)

l_int32	barcodeFormatIsSupported (l_int32 format)

Detailed Description


     Dispatcher
         char            *barcodeDispatchDecoder()

     Format Determination
         static l_int32   barcodeFindFormat()
         l_int32          barcodeFormatIsSupported()
         static l_int32   barcodeVerifyFormat()

     Decode 2 of 5
         static char     *barcodeDecode2of5()

     Decode Interleaved 2 of 5
         static char     *barcodeDecodeI2of5()

     Decode Code 93
         static char     *barcodeDecode93()

     Decode Code 39
         static char     *barcodeDecode39()

     Decode Codabar
         static char     *barcodeDecodeCodabar()

     Decode UPC-A
         static char     *barcodeDecodeUpca()

     Decode EAN 13
         static char     *barcodeDecodeEan13()

Definition in file bardecode.c.

Macro Definition Documentation

◆ DEBUG_CODES

#define DEBUG_CODES 0

Definition at line 82 of file bardecode.c.

Function Documentation

◆ barcodeDecode2of5()

static char * barcodeDecode2of5	(	char *	barstr,
		l_int32	debugflag
	)

static

barcodeDecode2of5()

Parameters

[in]	barstr	of widths, in set {1, 2}
[in]	debugflag

Returns: data string of digits, or NULL if none found or on error

Notes:
     (1) Ref: http://en.wikipedia.org/wiki/Two-out-of-five_code (Note:
                the codes given here are wrong!)
              http://morovia.com/education/symbology/code25.asp
     (2) This is a very low density encoding for the 10 digits.
         Each digit is encoded with 5 black bars, of which 2 are wide
         and 3 are narrow.  No information is carried in the spaces
         between the bars, which are all equal in width, represented by
         a "1" in our encoding.
     (3) The mapping from the sequence of five bar widths to the
         digit is identical to the mapping used by the interleaved
         2 of 5 code.  The start code is 21211, representing two
         wide bars and a narrow bar, and the interleaved "1" spaces
         are explicit.  The stop code is 21112.  For all codes
         (including start and stop), the trailing space "1" is
         implicit -- there is no reason to represent it in the
         Code2of5[] array.

Definition at line 378 of file bardecode.c.

References barcodeVerifyFormat(), lept_stderr(), stringNew(), and stringReverse().

Referenced by barcodeDispatchDecoder().

◆ barcodeDecode39()

static char * barcodeDecode39	(	char *	barstr,
		l_int32	debugflag
	)

static

barcodeDecode39()

Parameters

[in]	barstr	of widths, in set {1, 2}
[in]	debugflag

Returns: data string of digits, or NULL if none found or on error

Notes:
     (1) Ref:  http://en.wikipedia.org/wiki/Code39
               http://morovia.com/education/symbology/code39.asp
     (2) Each symbol has 5 black and 4 white bars.
         The start and stop codes are 121121211 (the asterisk)
     (3) This decoder was contributed by Roger Hyde.

Definition at line 672 of file bardecode.c.

References barcodeVerifyFormat(), lept_stderr(), stringNew(), and stringReverse().

Referenced by barcodeDispatchDecoder().

◆ barcodeDecode93()

static char * barcodeDecode93	(	char *	barstr,
		l_int32	debugflag
	)

static

barcodeDecode93()

Parameters

[in]	barstr	of widths, in set {1, 2, 3, 4}
[in]	debugflag

Returns: data string of digits, or NULL if none found or on error

Notes:
     (1) Ref:  http://en.wikipedia.org/wiki/Code93
               http://morovia.com/education/symbology/code93.asp
     (2) Each symbol has 3 black and 3 white bars.
         The start and stop codes are 111141; the stop code then is
         terminated with a final (1) bar.
     (3) The last two codes are check codes.  We are checking them
         for correctness, and issuing a warning on failure.  Should
         probably not return any data on failure.

Definition at line 555 of file bardecode.c.

References barcodeVerifyFormat(), lept_stderr(), stringNew(), and stringReverse().

Referenced by barcodeDispatchDecoder().

◆ barcodeDecodeCodabar()

static char * barcodeDecodeCodabar	(	char *	barstr,
		l_int32	debugflag
	)

static

barcodeDecodeCodabar()

Parameters

[in]	barstr	of widths, in set {1, 2}
[in]	debugflag

Returns: data string of digits, or NULL if none found or on error

Notes:
     (1) Ref:  http://en.wikipedia.org/wiki/Codabar
               http://morovia.com/education/symbology/codabar.asp
     (2) Each symbol has 4 black and 3 white bars.  They represent the
         10 digits, and optionally 6 other characters.  The start and
         stop codes can be any of four (typically denoted A,B,C,D).

Definition at line 755 of file bardecode.c.

References barcodeVerifyFormat(), lept_stderr(), stringNew(), and stringReverse().

Referenced by barcodeDispatchDecoder().

◆ barcodeDecodeEan13()

static char * barcodeDecodeEan13	(	char *	barstr,
		l_int32	first,
		l_int32	debugflag
	)

static

barcodeDecodeEan13()

Parameters

[in]	barstr	of widths, in set {1, 2, 3, 4}
[in]	first	first digit: 0 - 9
[in]	debugflag

Returns: data string of digits, or NULL if none found or on error

Notes:
     (1) Ref:  http://en.wikipedia.org/wiki/UniversalProductCode
               http://morovia.com/education/symbology/ean-13.asp
     (2) The encoding is essentially the same as UPC-A, except
         there are 13 digits in total, of which 12 are encoded
         by bars (as with UPC-A) and the 13th is a leading digit
         that determines the encoding of the next 6 digits,
         selecting each digit from one of two tables.
         encoded in the bars (as with UPC-A).  If the first digit
         is 0, the encoding is identical to UPC-A.
     (3) As with UPC-A, the last digit is a check digit.
     (4) For now, we assume the first digit is input to this function.
         Eventually, we will read it by pattern matching.

   TODO: fix this for multiple tables, depending on the value of first

Definition at line 960 of file bardecode.c.

References barcodeVerifyFormat(), lept_stderr(), stringNew(), and stringReverse().

Referenced by barcodeDispatchDecoder().

◆ barcodeDecodeI2of5()

static char * barcodeDecodeI2of5	(	char *	barstr,
		l_int32	debugflag
	)

static

barcodeDecodeI2of5()

Parameters

[in]	barstr	of widths, in set {1, 2}
[in]	debugflag

Returns: data string of digits, or NULL if none found or on error

Notes:
     (1) Ref: http://en.wikipedia.org/wiki/Interleaved_2_of_5
     (2) This always encodes an even number of digits.
         The start code is 1111; the stop code is 211.

Definition at line 458 of file bardecode.c.

References barcodeVerifyFormat(), lept_stderr(), stringNew(), and stringReverse().

Referenced by barcodeDispatchDecoder().

◆ barcodeDecodeUpca()

static char * barcodeDecodeUpca	(	char *	barstr,
		l_int32	debugflag
	)

static

barcodeDecodeUpca()

Parameters

[in]	barstr	of widths, in set {1, 2, 3, 4}
[in]	debugflag

Returns: data string of digits, or NULL if none found or on error

Notes:
     (1) Ref:  http://en.wikipedia.org/wiki/UniversalProductCode
               http://morovia.com/education/symbology/upc-a.asp
     (2) Each symbol has 2 black and 2 white bars, and encodes a digit.
         The start and stop codes are 111 and 111.  There are a total of
         30 black bars, encoding 12 digits in two sets of 6, with
         2 black bars separating the sets.
     (3) The last digit is a check digit.  We check for correctness, and
         issue a warning on failure.  Should probably not return any
         data on failure.

Definition at line 843 of file bardecode.c.

References barcodeVerifyFormat(), lept_stderr(), stringNew(), and stringReverse().

Referenced by barcodeDispatchDecoder().

◆ barcodeDispatchDecoder()

char * barcodeDispatchDecoder	(	char *	barstr,
		l_int32	format,
		l_int32	debugflag
	)

barcodeDispatchDecoder()

Parameters

[in]	barstr	string of integers in set {1,2,3,4} of bar widths
[in]	format	L_BF_ANY, L_BF_CODEI2OF5, L_BF_CODE93, ...
[in]	debugflag	use 1 to generate debug output

Returns: data string of decoded barcode data, or NULL on error

Definition at line 97 of file bardecode.c.

References barcodeDecode2of5(), barcodeDecode39(), barcodeDecode93(), barcodeDecodeCodabar(), barcodeDecodeEan13(), barcodeDecodeI2of5(), barcodeDecodeUpca(), and barcodeFindFormat().

◆ barcodeFindFormat()

static l_int32 barcodeFindFormat ( char * barstr )

static

barcodeFindFormat()

Parameters

[in] barstr of barcode widths, in set {1,2,3,4}

Returns: format for barcode, or L_BF_UNKNOWN if not recognized

Definition at line 144 of file bardecode.c.

References barcodeVerifyFormat().

Referenced by barcodeDispatchDecoder().

◆ barcodeFormatIsSupported()

l_int32 barcodeFormatIsSupported ( l_int32 format )

barcodeFormatIsSupported()

Parameters

[in] format

Returns: 1 if format is one of those supported; 0 otherwise

Definition at line 174 of file bardecode.c.

Referenced by pixProcessBarcodes(), and pixReadBarcodes().

◆ barcodeVerifyFormat()

static l_int32 barcodeVerifyFormat	(	char *	barstr,
		l_int32	format,
		l_int32 *	pvalid,
		l_int32 *	preverse
	)

static

barcodeVerifyFormat()

Parameters

[in]	barstr	of barcode widths, in set {1,2,3,4}
[in]	format	L_BF_CODEI2OF5, L_BF_CODE93, ...
[out]	pvalid	0 if not valid, 1 and 2 if valid
[out]	preverse	[optional] 1 if reversed; 0 otherwise

Returns: 0 if OK, 1 on error

Notes:
     (1) If valid == 1, the barcode is of the given format in the
         forward order; if valid == 2, it is backwards.
     (2) If the barcode needs to be reversed to read it, and &reverse
         is provided, a 1 is put into reverse.
     (3) Require at least 12 data bits, in addition to format identifiers.
         (TODO) If the barcode has a fixed length, this should be used
         explicitly, as is done for L_BF_UPCA and L_BF_EAN13.
     (4) (TODO) Add to this as more formats are supported.

Definition at line 208 of file bardecode.c.

References stringReverse().

Referenced by barcodeDecode2of5(), barcodeDecode39(), barcodeDecode93(), barcodeDecodeCodabar(), barcodeDecodeEan13(), barcodeDecodeI2of5(), barcodeDecodeUpca(), and barcodeFindFormat().

Macros

Functions

Detailed Description

Macro Definition Documentation

◆ DEBUG_CODES

Function Documentation

◆ barcodeDecode2of5()

◆ barcodeDecode39()

◆ barcodeDecode93()

◆ barcodeDecodeCodabar()

◆ barcodeDecodeEan13()

◆ barcodeDecodeI2of5()

◆ barcodeDecodeUpca()

◆ barcodeDispatchDecoder()

◆ barcodeFindFormat()

◆ barcodeFormatIsSupported()

◆ barcodeVerifyFormat()