Ryo Hagimoto / zbar_010

ZBar bar code reader . http://zbar.sourceforge.net/ ZBar is licensed under the GNU LGPL 2.1 to enable development of both open source and commercial projects.

Dependents:   GR-PEACH_Camera_in_barcode levkov_ov7670

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zbar.h File Reference
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zbar.h File Reference

ZBar Barcode Reader C API definition. More...

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Namespaces

namespace  zbar
 

C++ namespace for library interfaces.


Global library interfaces

enum  zbar_color_e { ZBAR_SPACE = 0, ZBAR_BAR = 1 }
 

"color" of element: bar or space.

More...
enum  zbar_symbol_type_e {
  ZBAR_NONE = 0, ZBAR_PARTIAL = 1, ZBAR_EAN8 = 8, ZBAR_UPCE = 9,
  ZBAR_ISBN10 = 10, ZBAR_UPCA = 12, ZBAR_EAN13 = 13, ZBAR_ISBN13 = 14,
  ZBAR_I25 = 25, ZBAR_CODE39 = 39, ZBAR_PDF417 = 57, ZBAR_QRCODE = 64,
  ZBAR_CODE128 = 128, ZBAR_SYMBOL = 0x00ff, ZBAR_ADDON2 = 0x0200, ZBAR_ADDON5 = 0x0500,
  ZBAR_ADDON = 0x0700
}
 

decoded symbol type.

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enum  zbar_error_e {
  ZBAR_OK = 0, ZBAR_ERR_NOMEM, ZBAR_ERR_INTERNAL, ZBAR_ERR_UNSUPPORTED,
  ZBAR_ERR_INVALID, ZBAR_ERR_SYSTEM, ZBAR_ERR_LOCKING, ZBAR_ERR_BUSY,
  ZBAR_ERR_XDISPLAY, ZBAR_ERR_XPROTO, ZBAR_ERR_CLOSED, ZBAR_ERR_WINAPI,
  ZBAR_ERR_NUM
}
 

error codes.

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enum  zbar_config_e {
  ZBAR_CFG_ENABLE = 0, ZBAR_CFG_ADD_CHECK, ZBAR_CFG_EMIT_CHECK, ZBAR_CFG_ASCII,
  ZBAR_CFG_NUM, ZBAR_CFG_MIN_LEN = 0x20, ZBAR_CFG_MAX_LEN, ZBAR_CFG_POSITION = 0x80,
  ZBAR_CFG_X_DENSITY = 0x100, ZBAR_CFG_Y_DENSITY
}
 

decoder configuration options.

More...
typedef enum zbar::zbar_color_e zbar_color_t
 "color" of element: bar or space.
typedef enum
zbar::zbar_symbol_type_e 		zbar_symbol_type_t
 decoded symbol type.
typedef enum zbar::zbar_error_e zbar_error_t
 error codes.
typedef enum zbar::zbar_config_e zbar_config_t
 decoder configuration options.
int zbar_version (unsigned *major, unsigned *minor)
 retrieve runtime library version information.
void zbar_set_verbosity (int verbosity)
 set global library debug level.
void zbar_increase_verbosity (void)
 increase global library debug level.
const char * zbar_get_symbol_name (zbar_symbol_type_t sym)
 retrieve string name for symbol encoding.
const char * zbar_get_addon_name (zbar_symbol_type_t sym)
 retrieve string name for addon encoding.
int zbar_parse_config (const char *config_string, zbar_symbol_type_t *symbology, zbar_config_t *config, int *value)
 parse a configuration string of the form "[symbology.]config[=value]".
int _zbar_error_spew (const void *object, int verbosity)
const char * _zbar_error_string (const void *object, int verbosity)
zbar_error_t _zbar_get_error_code (const void *object)

Symbol interface

decoded barcode symbol result object.

stores type, data, and image location of decoded symbol. all memory is owned by the library


typedef struct zbar_symbol_s zbar_symbol_t
 opaque decoded symbol object.
void zbar_symbol_ref (const zbar_symbol_t *symbol, int refs)
 symbol reference count manipulation.
zbar_symbol_type_t zbar_symbol_get_type (const zbar_symbol_t *symbol)
 retrieve type of decoded symbol.
const char * zbar_symbol_get_data (const zbar_symbol_t *symbol)
 retrieve data decoded from symbol.
unsigned int zbar_symbol_get_data_length (const zbar_symbol_t *symbol)
 retrieve length of binary data.
int zbar_symbol_get_quality (const zbar_symbol_t *symbol)
 retrieve a symbol confidence metric.
int zbar_symbol_get_count (const zbar_symbol_t *symbol)
 retrieve current cache count.
unsigned zbar_symbol_get_loc_size (const zbar_symbol_t *symbol)
 retrieve the number of points in the location polygon.
int zbar_symbol_get_loc_x (const zbar_symbol_t *symbol, unsigned index)
 retrieve location polygon x-coordinates.
int zbar_symbol_get_loc_y (const zbar_symbol_t *symbol, unsigned index)
 retrieve location polygon y-coordinates.
const zbar_symbol_t * zbar_symbol_next (const zbar_symbol_t *symbol)
 iterate the set to which this symbol belongs (there can be only one).
const zbar_symbol_set_t * zbar_symbol_get_components (const zbar_symbol_t *symbol)
 retrieve components of a composite result.
const zbar_symbol_t * zbar_symbol_first_component (const zbar_symbol_t *symbol)
 iterate components of a composite result.
char * zbar_symbol_xml (const zbar_symbol_t *symbol, char **buffer, unsigned *buflen)
 print XML symbol element representation to user result buffer.

Symbol Set interface

container for decoded result symbols associated with an image or a composite symbol.

Since:
0.10

typedef struct zbar_symbol_set_s zbar_symbol_set_t
 opaque symbol iterator object.
void zbar_symbol_set_ref (const zbar_symbol_set_t *symbols, int refs)
 reference count manipulation.
int zbar_symbol_set_get_size (const zbar_symbol_set_t *symbols)
 retrieve set size.
const zbar_symbol_t * zbar_symbol_set_first_symbol (const zbar_symbol_set_t *symbols)
 set iterator.

Image interface

stores image data samples along with associated format and size metadata


typedef struct zbar_image_s zbar_image_t
 opaque image object.
typedef void( zbar_image_cleanup_handler_t )(zbar_image_t *image)
 cleanup handler callback function.
typedef void( zbar_image_data_handler_t )(zbar_image_t *image, const void *userdata)
 data handler callback function.
zbar_image_t * zbar_image_create (void)
 new image constructor.
void zbar_image_destroy (zbar_image_t *image)
 image destructor.
void zbar_image_ref (zbar_image_t *image, int refs)
 image reference count manipulation.
zbar_image_t * zbar_image_convert (const zbar_image_t *image, unsigned long format)
 image format conversion.
zbar_image_t * zbar_image_convert_resize (const zbar_image_t *image, unsigned long format, unsigned width, unsigned height)
 image format conversion with crop/pad.
unsigned long zbar_image_get_format (const zbar_image_t *image)
 retrieve the image format.
unsigned zbar_image_get_sequence (const zbar_image_t *image)
 retrieve a "sequence" (page/frame) number associated with this image.
unsigned zbar_image_get_width (const zbar_image_t *image)
 retrieve the width of the image.
unsigned zbar_image_get_height (const zbar_image_t *image)
 retrieve the height of the image.
const void * zbar_image_get_data (const zbar_image_t *image)
 return the image sample data.
unsigned long zbar_image_get_data_length (const zbar_image_t *img)
 return the size of image data.
const zbar_symbol_set_t * zbar_image_get_symbols (const zbar_image_t *image)
 retrieve the decoded results.
void zbar_image_set_symbols (zbar_image_t *image, const zbar_symbol_set_t *symbols)
 associate the specified symbol set with the image, replacing any existing results.
const zbar_symbol_t * zbar_image_first_symbol (const zbar_image_t *image)
 image_scanner decode result iterator.
void zbar_image_set_format (zbar_image_t *image, unsigned long format)
 specify the fourcc image format code for image sample data.
void zbar_image_set_sequence (zbar_image_t *image, unsigned sequence_num)
 associate a "sequence" (page/frame) number with this image.
void zbar_image_set_size (zbar_image_t *image, unsigned width, unsigned height)
 specify the pixel size of the image.
void zbar_image_set_data (zbar_image_t *image, const void *data, unsigned long data_byte_length, zbar_image_cleanup_handler_t *cleanup_hndlr)
 specify image sample data.
void zbar_image_free_data (zbar_image_t *image)
 built-in cleanup handler.
void zbar_image_set_userdata (zbar_image_t *image, void *userdata)
 associate user specified data value with an image.
void * zbar_image_get_userdata (const zbar_image_t *image)
 return user specified data value associated with the image.
int zbar_image_write (const zbar_image_t *image, const char *filebase)
 dump raw image data to a file for debug.
zbar_image_t * zbar_image_read (char *filename)
 read back an image in the format written by zbar_image_write()

Processor interface

high-level self-contained image processor. processes video and images for barcodes, optionally displaying images to a library owned output window


typedef struct zbar_processor_s zbar_processor_t
 opaque standalone processor object.
zbar_processor_t * zbar_processor_create (int threaded)
 constructor.
void zbar_processor_destroy (zbar_processor_t *processor)
 destructor.
int zbar_processor_init (zbar_processor_t *processor, const char *video_device, int enable_display)
 (re)initialization.
int zbar_processor_request_size (zbar_processor_t *processor, unsigned width, unsigned height)
 request a preferred size for the video image from the device.
int zbar_processor_request_interface (zbar_processor_t *processor, int version)
 request a preferred video driver interface version for debug/testing.
int zbar_processor_request_iomode (zbar_processor_t *video, int iomode)
 request a preferred video I/O mode for debug/testing.
int zbar_processor_force_format (zbar_processor_t *processor, unsigned long input_format, unsigned long output_format)
 force specific input and output formats for debug/testing.
zbar_image_data_handler_t * zbar_processor_set_data_handler (zbar_processor_t *processor, zbar_image_data_handler_t *handler, const void *userdata)
 setup result handler callback.
void zbar_processor_set_userdata (zbar_processor_t *processor, void *userdata)
 associate user specified data value with the processor.
void * zbar_processor_get_userdata (const zbar_processor_t *processor)
 return user specified data value associated with the processor.
int zbar_processor_set_config (zbar_processor_t *processor, zbar_symbol_type_t symbology, zbar_config_t config, int value)
 set config for indicated symbology (0 for all) to specified value.
static int zbar_processor_parse_config (zbar_processor_t *processor, const char *config_string)
 parse configuration string using zbar_parse_config() and apply to processor using zbar_processor_set_config().
int zbar_processor_is_visible (zbar_processor_t *processor)
 retrieve the current state of the ouput window.
int zbar_processor_set_visible (zbar_processor_t *processor, int visible)
 show or hide the display window owned by the library.
int zbar_processor_set_active (zbar_processor_t *processor, int active)
 control the processor in free running video mode.
const zbar_symbol_set_t * zbar_processor_get_results (const zbar_processor_t *processor)
 retrieve decode results for last scanned image/frame.
int zbar_processor_user_wait (zbar_processor_t *processor, int timeout)
 wait for input to the display window from the user (via mouse or keyboard).
int zbar_process_one (zbar_processor_t *processor, int timeout)
 process from the video stream until a result is available, or the timeout (in milliseconds) expires.
int zbar_process_image (zbar_processor_t *processor, zbar_image_t *image)
 process the provided image for barcodes.
static int zbar_processor_error_spew (const zbar_processor_t *processor, int verbosity)
 display detail for last processor error to stderr.
static const char * zbar_processor_error_string (const zbar_processor_t *processor, int verbosity)
 retrieve the detail string for the last processor error.
static zbar_error_t zbar_processor_get_error_code (const zbar_processor_t *processor)
 retrieve the type code for the last processor error.

Video interface

mid-level video source abstraction. captures images from a video device


typedef struct zbar_video_s zbar_video_t
 opaque video object.
zbar_video_t * zbar_video_create (void)
 constructor.
void zbar_video_destroy (zbar_video_t *video)
 destructor.
int zbar_video_open (zbar_video_t *video, const char *device)
 open and probe a video device.
int zbar_video_get_fd (const zbar_video_t *video)
 retrieve file descriptor associated with open *nix video device useful for using select()/poll() to tell when new images are available (NB v4l2 only!!).
int zbar_video_request_size (zbar_video_t *video, unsigned width, unsigned height)
 request a preferred size for the video image from the device.
int zbar_video_request_interface (zbar_video_t *video, int version)
 request a preferred driver interface version for debug/testing.
int zbar_video_request_iomode (zbar_video_t *video, int iomode)
 request a preferred I/O mode for debug/testing.
int zbar_video_get_width (const zbar_video_t *video)
 retrieve current output image width.
int zbar_video_get_height (const zbar_video_t *video)
 retrieve current output image height.
int zbar_video_init (zbar_video_t *video, unsigned long format)
 initialize video using a specific format for debug.
int zbar_video_enable (zbar_video_t *video, int enable)
 start/stop video capture.
zbar_image_t * zbar_video_next_image (zbar_video_t *video)
 retrieve next captured image.
static int zbar_video_error_spew (const zbar_video_t *video, int verbosity)
 display detail for last video error to stderr.
static const char * zbar_video_error_string (const zbar_video_t *video, int verbosity)
 retrieve the detail string for the last video error.
static zbar_error_t zbar_video_get_error_code (const zbar_video_t *video)
 retrieve the type code for the last video error.

Window interface

mid-level output window abstraction. displays images to user-specified platform specific output window


typedef struct zbar_window_s zbar_window_t
 opaque window object.
zbar_window_t * zbar_window_create (void)
 constructor.
void zbar_window_destroy (zbar_window_t *window)
 destructor.
int zbar_window_attach (zbar_window_t *window, void *x11_display_w32_hwnd, unsigned long x11_drawable)
 associate reader with an existing platform window.
void zbar_window_set_overlay (zbar_window_t *window, int level)
 control content level of the reader overlay.
int zbar_window_get_overlay (const zbar_window_t *window)
 retrieve current content level of reader overlay.
int zbar_window_draw (zbar_window_t *window, zbar_image_t *image)
 draw a new image into the output window.
int zbar_window_redraw (zbar_window_t *window)
 redraw the last image (exposure handler).
int zbar_window_resize (zbar_window_t *window, unsigned width, unsigned height)
 resize the image window (reconfigure handler).
static int zbar_window_error_spew (const zbar_window_t *window, int verbosity)
 display detail for last window error to stderr.
static const char * zbar_window_error_string (const zbar_window_t *window, int verbosity)
 retrieve the detail string for the last window error.
static zbar_error_t zbar_window_get_error_code (const zbar_window_t *window)
 retrieve the type code for the last window error.
int zbar_negotiate_format (zbar_video_t *video, zbar_window_t *window)
 select a compatible format between video input and output window.

Image Scanner interface

mid-level image scanner interface. reads barcodes from 2-D images


typedef struct zbar_image_scanner_s zbar_image_scanner_t
 opaque image scanner object.
zbar_image_scanner_t * zbar_image_scanner_create (void)
 constructor.
void zbar_image_scanner_destroy (zbar_image_scanner_t *scanner)
 destructor.
zbar_image_data_handler_t * zbar_image_scanner_set_data_handler (zbar_image_scanner_t *scanner, zbar_image_data_handler_t *handler, const void *userdata)
 setup result handler callback.
int zbar_image_scanner_set_config (zbar_image_scanner_t *scanner, zbar_symbol_type_t symbology, zbar_config_t config, int value)
 set config for indicated symbology (0 for all) to specified value.
static int zbar_image_scanner_parse_config (zbar_image_scanner_t *scanner, const char *config_string)
 parse configuration string using zbar_parse_config() and apply to image scanner using zbar_image_scanner_set_config().
void zbar_image_scanner_enable_cache (zbar_image_scanner_t *scanner, int enable)
 enable or disable the inter-image result cache (default disabled).
void zbar_image_scanner_recycle_image (zbar_image_scanner_t *scanner, zbar_image_t *image)
 remove any previously decoded results from the image scanner and the specified image.
const zbar_symbol_set_t * zbar_image_scanner_get_results (const zbar_image_scanner_t *scanner)
 retrieve decode results for last scanned image.
int zbar_scan_image (zbar_image_scanner_t *scanner, zbar_image_t *image)
 scan for symbols in provided image.

Decoder interface

low-level bar width stream decoder interface. identifies symbols and extracts encoded data


typedef struct zbar_decoder_s zbar_decoder_t
 opaque decoder object.
typedef void( zbar_decoder_handler_t )(zbar_decoder_t *decoder)
 decoder data handler callback function.
zbar_decoder_t * zbar_decoder_create (void)
 constructor.
void zbar_decoder_destroy (zbar_decoder_t *decoder)
 destructor.
int zbar_decoder_set_config (zbar_decoder_t *decoder, zbar_symbol_type_t symbology, zbar_config_t config, int value)
 set config for indicated symbology (0 for all) to specified value.
static int zbar_decoder_parse_config (zbar_decoder_t *decoder, const char *config_string)
 parse configuration string using zbar_parse_config() and apply to decoder using zbar_decoder_set_config().
void zbar_decoder_reset (zbar_decoder_t *decoder)
 clear all decoder state.
void zbar_decoder_new_scan (zbar_decoder_t *decoder)
 mark start of a new scan pass.
zbar_symbol_type_t zbar_decode_width (zbar_decoder_t *decoder, unsigned width)
 process next bar/space width from input stream.
zbar_color_t zbar_decoder_get_color (const zbar_decoder_t *decoder)
 retrieve color of next element passed to zbar_decode_width().
const char * zbar_decoder_get_data (const zbar_decoder_t *decoder)
 retrieve last decoded data.
unsigned int zbar_decoder_get_data_length (const zbar_decoder_t *decoder)
 retrieve length of binary data.
zbar_symbol_type_t zbar_decoder_get_type (const zbar_decoder_t *decoder)
 retrieve last decoded symbol type.
zbar_decoder_handler_t * zbar_decoder_set_handler (zbar_decoder_t *decoder, zbar_decoder_handler_t *handler)
 setup data handler callback.
void zbar_decoder_set_userdata (zbar_decoder_t *decoder, void *userdata)
 associate user specified data value with the decoder.
void * zbar_decoder_get_userdata (const zbar_decoder_t *decoder)
 return user specified data value associated with the decoder.

Scanner interface

low-level linear intensity sample stream scanner interface. identifies "bar" edges and measures width between them. optionally passes to bar width decoder


typedef struct zbar_scanner_s zbar_scanner_t
 opaque scanner object.
zbar_scanner_t * zbar_scanner_create (zbar_decoder_t *decoder)
 constructor.
void zbar_scanner_destroy (zbar_scanner_t *scanner)
 destructor.
zbar_symbol_type_t zbar_scanner_reset (zbar_scanner_t *scanner)
 clear all scanner state.
zbar_symbol_type_t zbar_scanner_new_scan (zbar_scanner_t *scanner)
 mark start of a new scan pass.
zbar_symbol_type_t zbar_scanner_flush (zbar_scanner_t *scanner)
 flush scanner processing pipeline.
zbar_symbol_type_t zbar_scan_y (zbar_scanner_t *scanner, int y)
 process next sample intensity value.
static zbar_symbol_type_t zbar_scan_rgb24 (zbar_scanner_t *scanner, unsigned char *rgb)
 process next sample from RGB (or BGR) triple.
unsigned zbar_scanner_get_width (const zbar_scanner_t *scanner)
 retrieve last scanned width.
unsigned zbar_scanner_get_edge (const zbar_scanner_t *scn, unsigned offset, int prec)
 retrieve sample position of last edge.
zbar_color_t zbar_scanner_get_color (const zbar_scanner_t *scanner)
 retrieve last scanned color.

Detailed Description

ZBar Barcode Reader C API definition.

Definition in file zbar.h.

Generated on Tue Jul 12 2022 18:54:12 by  doxygen 1.7.2