detector.c File Reference

JABCode detector. More...

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include "jabcode.h"
#include "detector.h"
#include "decoder.h"
#include "encoder.h"

Functions
jab_boolean	checkPatternCross (jab_int32 *state_count, jab_float *module_size)
	Check the proportion of layer sizes in finder pattern. More...
jab_boolean	checkModuleSize (jab_float size_r, jab_float size_g, jab_float size_b)
	Check if the input module sizes are the same. More...
jab_boolean	seekPattern (jab_bitmap *ch, jab_int32 row, jab_int32 col, jab_int32 *start, jab_int32 *end, jab_float *center, jab_float *module_size, jab_int32 *skip)
	Find a candidate scanline of finder pattern. More...
jab_boolean	seekPatternHorizontal (jab_byte *row, jab_int32 *startx, jab_int32 *endx, jab_float *centerx, jab_float *module_size, jab_int32 *skip)
	Find a candidate horizontal scanline of finder pattern. More...
jab_int32	crossCheckPatternDiagonal (jab_bitmap *image, jab_int32 type, jab_float module_size_max, jab_float *centerx, jab_float *centery, jab_float *module_size, jab_int32 *dir, jab_boolean both_dir)
	Crosscheck the finder pattern candidate in diagonal direction. More...
jab_boolean	crossCheckPatternVertical (jab_bitmap *image, jab_int32 module_size_max, jab_float centerx, jab_float *centery, jab_float *module_size)
	Crosscheck the finder pattern candidate in vertical direction. More...
jab_boolean	crossCheckPatternHorizontal (jab_bitmap *image, jab_float module_size_max, jab_float *centerx, jab_float centery, jab_float *module_size)
	Crosscheck the finder pattern candidate in horizontal direction. More...
jab_boolean	crossCheckPatternCh (jab_bitmap *ch, jab_int32 type, jab_int32 h_v, jab_float module_size_max, jab_float *module_size, jab_float *centerx, jab_float *centery, jab_int32 *dir, jab_int32 *dcc)
	Crosscheck the finder pattern candidate in one channel. More...
jab_boolean	crossCheckPattern (jab_bitmap *ch[], jab_finder_pattern *fp, jab_int32 h_v)
	Crosscheck the finder pattern candidate. More...
jab_int32	saveAlignmentPattern (jab_alignment_pattern *ap, jab_alignment_pattern *aps, jab_int32 *counter)
	Save a found alignment pattern into the alignment pattern list. More...
void	saveFinderPattern (jab_finder_pattern *fp, jab_finder_pattern *fps, jab_int32 *counter, jab_int32 *fp_type_count)
	Save a found finder pattern into the finder pattern list. More...
void	drawFoundFinderPatterns (jab_finder_pattern *fps, jab_int32 number, jab_int32 color)
void	removeBadPatterns (jab_finder_pattern *fps, jab_int32 fp_count, jab_float mean, jab_float threshold)
	Remove the finder patterns with greatly different module size. More...
jab_finder_pattern	getBestPattern (jab_finder_pattern *fps, jab_int32 fp_count)
	Find the finder pattern with most detected times. More...
jab_int32	selectBestPatterns (jab_finder_pattern *fps, jab_int32 fp_count, jab_int32 *fp_type_count)
	Select the best finder patterns out of the list. More...
void	scanPatternVertical (jab_bitmap *ch[], jab_int32 min_module_size, jab_finder_pattern *fps, jab_int32 *fp_type_count, jab_int32 *total_finder_patterns)
	Scan the image vertically. More...
jab_finder_pattern *	findMasterSymbol (jab_bitmap *ch[], jab_detect_mode mode)
	Find the master symbol in the image. More...
jab_float	crossCheckPatternDiagonalAP (jab_bitmap *image, jab_int32 ap_type, jab_int32 module_size_max, jab_point center, jab_int32 *dir)
	Crosscheck the alignment pattern candidate in diagonal direction. More...
jab_float	crossCheckPatternVerticalAP (jab_bitmap *image, jab_point center, jab_int32 module_size_max, jab_float *module_size)
	Crosscheck the alignment pattern candidate in vertical direction. More...
jab_float	crossCheckPatternHorizontalAP (jab_byte *row, jab_int32 channel, jab_int32 startx, jab_int32 endx, jab_int32 centerx, jab_int32 ap_type, jab_float module_size_max, jab_float *module_size)
	Crosscheck the alignment pattern candidate in horizontal direction. More...
jab_boolean	crossCheckPatternAP (jab_bitmap *ch[], jab_int32 y, jab_int32 minx, jab_int32 maxx, jab_int32 cur_x, jab_int32 ap_type, jab_float max_module_size, jab_float *centerx, jab_float *centery, jab_float *module_size, jab_int32 *dir)
	Crosscheck the alignment pattern. More...
jab_alignment_pattern	findAlignmentPattern (jab_bitmap *ch[], jab_float x, jab_float y, jab_float module_size, jab_int32 ap_type)
	Find alignment pattern around a given position. More...
jab_boolean	findSlaveSymbol (jab_bitmap *bitmap, jab_bitmap *ch[], jab_decoded_symbol *host_symbol, jab_decoded_symbol *slave_symbol, jab_int32 docked_position)
	Find a docked slave symbol. More...
jab_int32	getSideSize (jab_int32 size, jab_int32 *flag)
	Get the nearest valid side size to a given size. More...
jab_vector2d	calculateSideSize (jab_bitmap *ch[], jab_finder_pattern *fps, jab_float *module_size)
	Calculate the side sizes of master symbol. More...
jab_bitmap *	sampleSymbolByAlignmentPattern (jab_bitmap *bitmap, jab_bitmap *ch[], jab_decoded_symbol *symbol, jab_alignment_pattern *fps)
	Sample a symbol with help of alignment patterns. More...
jab_boolean	detectMaster (jab_bitmap *bitmap, jab_bitmap *ch[], jab_decoded_symbol *master_symbol)
	Detect and decode a master symbol. More...
jab_bitmap *	detectSlave (jab_bitmap *bitmap, jab_bitmap *ch[], jab_decoded_symbol *host_symbol, jab_decoded_symbol *slave_symbol, jab_int32 docked_position)
	Detect a slave symbol. More...
jab_boolean	decodeDockedSlaves (jab_bitmap *bitmap, jab_bitmap *ch[], jab_decoded_symbol *symbols, jab_int32 host_index, jab_int32 *total)
	Decode docked slave symbols around a host symbol. More...
void	preprocessImage (jab_bitmap *bitmap)
	Preprocess the image. More...
jab_data *	decodeJABCodeEx (jab_bitmap *bitmap, jab_int32 mode, jab_int32 *status, jab_decoded_symbol *symbols, jab_int32 max_symbol_number)
	Extended function to decode a JAB Code. More...
jab_data *	decodeJABCode (jab_bitmap *bitmap, jab_int32 mode, jab_int32 *status)
	Decode a JAB Code. More...

Detailed Description

JABCode detector.

libjabcode - JABCode Encoding/Decoding Library

Copyright 2016 by Fraunhofer SIT. All rights reserved. See LICENSE file for full terms of use and distribution.

Contact: Huajian Liu liu@s.nosp@m.it.f.nosp@m.raunh.nosp@m.ofer.nosp@m..de Waldemar Berchtold walde.nosp@m.mar..nosp@m.berch.nosp@m.told.nosp@m.@sit..nosp@m.frau.nosp@m.nhofe.nosp@m.r.de

Function Documentation

jab_vector2d calculateSideSize	(	jab_bitmap *	ch[],
		jab_finder_pattern *	fps,
		jab_float *	module_size
	)

Calculate the side sizes of master symbol.

Parameters

ch	the binarized color channels of the image
fps	the finder patterns
module_size	the module size

Returns

the horizontal and vertical side sizes

jab_boolean checkModuleSize	(	jab_float	size_r,
		jab_float	size_g,
		jab_float	size_b
	)

Check if the input module sizes are the same.

Parameters

size_r	the first module size
size_g	the second module size
size_b	the third module size

Returns

JAB_SUCCESS | JAB_FAILURE

jab_boolean checkPatternCross	(	jab_int32 *	state_count,
		jab_float *	module_size
	)

Check the proportion of layer sizes in finder pattern.

Parameters

state_count	the layer sizes in pixel
module_size	the module size

Returns

JAB_SUCCESS | JAB_FAILURE

jab_boolean crossCheckPattern	(	jab_bitmap *	ch[],
		jab_finder_pattern *	fp,
		jab_int32	h_v
	)

Crosscheck the finder pattern candidate.

Parameters

ch	the binarized color channels of the image
fp	the finder pattern
h_v	the direction of the candidate scanline, 0:horizontal 1:vertical

Returns

JAB_SUCCESS | JAB_FAILURE

jab_boolean crossCheckPatternAP	(	jab_bitmap *	ch[],
		jab_int32	y,
		jab_int32	minx,
		jab_int32	maxx,
		jab_int32	cur_x,
		jab_int32	ap_type,
		jab_float	max_module_size,
		jab_float *	centerx,
		jab_float *	centery,
		jab_float *	module_size,
		jab_int32 *	dir
	)

Crosscheck the alignment pattern.

Parameters

ch	the binarized color channels of the image
y	the y coordinate of the horizontal scanline
minx	the minimal coordinate of the horizontal scanline
maxx	the maximal coordinate of the horizontal scanline
cur_x	the start position of the horizontal scanline
ap_type	the alignment pattern type
max_module_size	the maximal allowed module size
centerx	the x coordinate of the alignment pattern center
centery	the y coordinate of the alignment pattern center
module_size	the module size in horizontal direction
dir	the alignment pattern direction

Returns

JAB_SUCCESS | JAB_FAILURE

jab_boolean crossCheckPatternCh	(	jab_bitmap *	ch,
		jab_int32	type,
		jab_int32	h_v,
		jab_float	module_size_max,
		jab_float *	module_size,
		jab_float *	centerx,
		jab_float *	centery,
		jab_int32 *	dir,
		jab_int32 *	dcc
	)

Crosscheck the finder pattern candidate in one channel.

Parameters

ch	the binarized color channel
type	the finder pattern type
h_v	the direction of the candidate scanline, 0:horizontal 1:vertical
module_size_max	the maximal allowed module size
module_size	the module size in all directions
centerx	the x coordinate of the finder pattern center
centery	the y coordinate of the finder pattern center
dir	the finder pattern direction
dcc	the diagonal crosscheck result

Returns

JAB_SUCCESS | JAB_FAILURE

jab_int32 crossCheckPatternDiagonal	(	jab_bitmap *	image,
		jab_int32	type,
		jab_float	module_size_max,
		jab_float *	centerx,
		jab_float *	centery,
		jab_float *	module_size,
		jab_int32 *	dir,
		jab_boolean	both_dir
	)

Crosscheck the finder pattern candidate in diagonal direction.

Parameters

image	the image bitmap
type	the finder pattern type
module_size_max	the maximal allowed module size
centerx	the x coordinate of the finder pattern center
centery	the y coordinate of the finder pattern center
module_size	the module size in diagonal direction
dir	the finder pattern direction
both_dir	scan both diagonal scanlines

Returns

the number of confirmed diagonal scanlines

jab_float crossCheckPatternDiagonalAP	(	jab_bitmap *	image,
		jab_int32	ap_type,
		jab_int32	module_size_max,
		jab_point	center,
		jab_int32 *	dir
	)

Crosscheck the alignment pattern candidate in diagonal direction.

Parameters

image	the image bitmap
ap_type	the alignment pattern type
module_size_max	the maximal allowed module size
center	the alignment pattern center
dir	the alignment pattern direction

Returns

the y coordinate of the diagonal scanline center | -1 if failed

jab_boolean crossCheckPatternHorizontal	(	jab_bitmap *	image,
		jab_float	module_size_max,
		jab_float *	centerx,
		jab_float	centery,
		jab_float *	module_size
	)

Crosscheck the finder pattern candidate in horizontal direction.

Parameters

image	the image bitmap
module_size_max	the maximal allowed module size
centerx	the x coordinate of the finder pattern center
centery	the y coordinate of the finder pattern center
module_size	the module size in horizontal direction

Returns

JAB_SUCCESS | JAB_FAILURE

jab_float crossCheckPatternHorizontalAP	(	jab_byte *	row,
		jab_int32	channel,
		jab_int32	startx,
		jab_int32	endx,
		jab_int32	centerx,
		jab_int32	ap_type,
		jab_float	module_size_max,
		jab_float *	module_size
	)

Crosscheck the alignment pattern candidate in horizontal direction.

Parameters

row	the bitmap row
channel	the color channel
startx	the start position
endx	the end position
centerx	the center of the candidate scanline
ap_type	the alignment pattern type
module_size_max	the maximal allowed module size
module_size	the module size in horizontal direction

Returns

the x coordinate of the horizontal scanline center | -1 if failed

jab_boolean crossCheckPatternVertical	(	jab_bitmap *	image,
		jab_int32	module_size_max,
		jab_float	centerx,
		jab_float *	centery,
		jab_float *	module_size
	)

Crosscheck the finder pattern candidate in vertical direction.

Parameters

image	the image bitmap
module_size_max	the maximal allowed module size
centerx	the x coordinate of the finder pattern center
centery	the y coordinate of the finder pattern center
module_size	the module size in vertical direction

Returns

JAB_SUCCESS | JAB_FAILURE

jab_float crossCheckPatternVerticalAP	(	jab_bitmap *	image,
		jab_point	center,
		jab_int32	module_size_max,
		jab_float *	module_size
	)

Crosscheck the alignment pattern candidate in vertical direction.

Parameters

image	the image bitmap
center	the alignment pattern center
module_size_max	the maximal allowed module size
module_size	the module size in vertical direction

Returns

the y coordinate of the vertical scanline center | -1 if failed

jab_boolean decodeDockedSlaves	(	jab_bitmap *	bitmap,
		jab_bitmap *	ch[],
		jab_decoded_symbol *	symbols,
		jab_int32	host_index,
		jab_int32 *	total
	)

Decode docked slave symbols around a host symbol.

Parameters

bitmap	the image bitmap
ch	the binarized color channels of the image
symbols	the symbol list
host_index	the index number of the host symbol
total	the number of symbols in the list

Returns

JAB_SUCCESS | JAB_FAILURE

jab_data* decodeJABCode	(	jab_bitmap *	bitmap,
		jab_int32	mode,
		jab_int32 *	status
	)

Decode a JAB Code.

Parameters

bitmap	the image bitmap
mode	the decoding mode(NORMAL_DECODE: only output completely decoded data when all symbols are correctly decoded COMPATIBLE_DECODE: also output partly decoded data even if some symbols are not correctly decoded
status	the decoding status code (0: not detectable, 1: not decodable, 2: partly decoded with COMPATIBLE_DECODE mode, 3: fully decoded)

Returns

the decoded data | NULL if failed

jab_data* decodeJABCodeEx	(	jab_bitmap *	bitmap,
		jab_int32	mode,
		jab_int32 *	status,
		jab_decoded_symbol *	symbols,
		jab_int32	max_symbol_number
	)

Extended function to decode a JAB Code.

Parameters

bitmap	the image bitmap
mode	the decoding mode(NORMAL_DECODE: only output completely decoded data when all symbols are correctly decoded COMPATIBLE_DECODE: also output partly decoded data even if some symbols are not correctly decoded
status	the decoding status code (0: not detectable, 1: not decodable, 2: partly decoded with COMPATIBLE_DECODE mode, 3: fully decoded)
symbols	the decoded symbols
max_symbol_number	the maximal possible number of symbols to be decoded

Returns

the decoded data | NULL if failed

jab_boolean detectMaster	(	jab_bitmap *	bitmap,
		jab_bitmap *	ch[],
		jab_decoded_symbol *	master_symbol
	)

Detect and decode a master symbol.

Parameters

bitmap	the image bitmap
ch	the binarized color channels of the image
master_symbol	the master symbol

Returns

JAB_SUCCESS | JAB_FAILURE

jab_bitmap* detectSlave	(	jab_bitmap *	bitmap,
		jab_bitmap *	ch[],
		jab_decoded_symbol *	host_symbol,
		jab_decoded_symbol *	slave_symbol,
		jab_int32	docked_position
	)

Detect a slave symbol.

Parameters

bitmap	the image bitmap
ch	the binarized color channels of the image
host_symbol	the host symbol
slave_symbol	the slave symbol
docked_position	the docked position

Returns

the sampled slave symbol matrix | NULL if failed

jab_alignment_pattern findAlignmentPattern	(	jab_bitmap *	ch[],
		jab_float	x,
		jab_float	y,
		jab_float	module_size,
		jab_int32	ap_type
	)

Find alignment pattern around a given position.

Parameters

ch	the binarized color channels of the image
x	the x coordinate of the given position
y	the y coordinate of the given position
module_size	the module size
ap_type	the alignment pattern type

Returns

the found alignment pattern

jab_finder_pattern* findMasterSymbol	(	jab_bitmap *	ch[],
		jab_detect_mode	mode
	)

Find the master symbol in the image.

Parameters

ch	the binarized color channels of the image
mode	the detection mode

Returns

the finder pattern list | NULL

jab_boolean findSlaveSymbol	(	jab_bitmap *	bitmap,
		jab_bitmap *	ch[],
		jab_decoded_symbol *	host_symbol,
		jab_decoded_symbol *	slave_symbol,
		jab_int32	docked_position
	)

Find a docked slave symbol.

Parameters

bitmap	the image bitmap
ch	the binarized color channels of the image
host_symbol	the host symbol
slave_symbol	the slave symbol
docked_position	the docked position

Returns

JAB_SUCCESS | JAB_FAILURE

jab_finder_pattern getBestPattern	(	jab_finder_pattern *	fps,
		jab_int32	fp_count
	)

Find the finder pattern with most detected times.

Parameters

fps	the finder pattern list
fp_count	the number of finder patterns in the list

jab_int32 getSideSize	(	jab_int32	size,
		jab_int32 *	flag
	)

Get the nearest valid side size to a given size.

Parameters

size	the input size
flag	the flag indicating the magnitude of error

Returns

the nearest valid side size

void preprocessImage

(

jab_bitmap *

bitmap

)

Preprocess the image.

Parameters

bitmap

the image bitmap

void removeBadPatterns	(	jab_finder_pattern *	fps,
		jab_int32	fp_count,
		jab_float	mean,
		jab_float	threshold
	)

Remove the finder patterns with greatly different module size.

Parameters

fps	the finder pattern list
fp_count	the number of finder patterns in the list
mean	the average module size
threshold	the tolerance threshold

jab_bitmap* sampleSymbolByAlignmentPattern	(	jab_bitmap *	bitmap,
		jab_bitmap *	ch[],
		jab_decoded_symbol *	symbol,
		jab_alignment_pattern *	fps
	)

Sample a symbol with help of alignment patterns.

Parameters

bitmap	the image bitmap
ch	the binarized color channels of the image
symbol	the symbol to be sampled
fps	the finder/alignment patterns

Returns

the sampled symbol matrix | NULL if failed

jab_int32 saveAlignmentPattern	(	jab_alignment_pattern *	ap,
		jab_alignment_pattern *	aps,
		jab_int32 *	counter
	)

Save a found alignment pattern into the alignment pattern list.

Parameters

ap	the alignment pattern
aps	the alignment pattern list
counter	the number of alignment patterns in the list

Returns

-1 if added as a new alignment pattern | the alignment pattern index if combined with an existing pattern

void saveFinderPattern	(	jab_finder_pattern *	fp,
		jab_finder_pattern *	fps,
		jab_int32 *	counter,
		jab_int32 *	fp_type_count
	)

Save a found finder pattern into the finder pattern list.

Parameters

fp	the finder pattern
fps	the finder pattern list
counter	the number of finder patterns in the list
fp_type_count	the number of finder pattern types in the list

void scanPatternVertical	(	jab_bitmap *	ch[],
		jab_int32	min_module_size,
		jab_finder_pattern *	fps,
		jab_int32 *	fp_type_count,
		jab_int32 *	total_finder_patterns
	)

Scan the image vertically.

Parameters

ch	the binarized color channels of the image
min_module_size	the minimal module size
fps	the found finder patterns
fp_type_count	the number of found finder patterns for each type
total_finder_patterns	the number of totally found finder patterns

jab_boolean seekPattern	(	jab_bitmap *	ch,
		jab_int32	row,
		jab_int32	col,
		jab_int32 *	start,
		jab_int32 *	end,
		jab_float *	center,
		jab_float *	module_size,
		jab_int32 *	skip
	)

Find a candidate scanline of finder pattern.

Parameters

ch	the image channel
row	the row to be scanned
col	the column to be scanned
start	the start position
end	the end position
center	the center of the candidate scanline
module_size	the module size
skip	the number of pixels to be skipped in the next scan

Returns

JAB_SUCCESS | JAB_FAILURE

jab_boolean seekPatternHorizontal	(	jab_byte *	row,
		jab_int32 *	startx,
		jab_int32 *	endx,
		jab_float *	centerx,
		jab_float *	module_size,
		jab_int32 *	skip
	)

Find a candidate horizontal scanline of finder pattern.

Parameters

row	the bitmap row
startx	the start position
endx	the end position
centerx	the center of the candidate scanline
module_size	the module size
skip	the number of pixels to be skipped in the next scan

Returns

JAB_SUCCESS | JAB_FAILURE

jab_int32 selectBestPatterns	(	jab_finder_pattern *	fps,
		jab_int32	fp_count,
		jab_int32 *	fp_type_count
	)

Select the best finder patterns out of the list.

Parameters

fps	the finder pattern list
fp_count	the number of finder patterns in the list
fp_type_count	the number of each finder pattern type

Returns

the number of missing finder pattern types