image.h

《Visual C++数字图像识别技术典型案例》之光学字符识别技术源码

/******************************************************************************
 * 光学字符识别程序
 * 文件名：image.h
 * 功能  ：图像处理相关函数定义
 * modified by [e-mail]
******************************************************************************/

#ifndef IMAGE_H
#define IMAGE_H

#include <vector>

#include <qpainter.h>
#include <qdialog.h>

#include "kognition.h"
#include "segimage.h"
#include "character.h"
#include "abstract_character.h"
#include "character_database.h"

class Image : public QDialog
{
	Q_OBJECT
	private:
		static const float cs_angle_treshold;
 		enum {
			max_iter       		= 5, 
			seq_min_inner_threshold = 2,
			seq_min_outer_threshold	= 4
		};

	public:
		Image( KognitionApp *parent = 0, const char *name = 0 );
		~Image();

		enum drawing_flags {
				draw_border_lists			= 0x00000001, 
				draw_border_angles			= 0x00000002, 
				draw_border_angles_smooth	= 0x00000004, 			
				draw_cross_sections			= 0x00000008, 
				draw_singular_regions		= 0x00000010, 
				draw_skeleton				= 0x00000020, 
				draw_directions				= 0x00000040, 
				draw_polygon_skeleton		= 0x00000080, 
				draw_grid					= 0x00000100, 
				draw_abstract_char			= 0x00000200, 
				draw_bw						= 0x00000400, 
				draw_guessed_lines			= 0x00000800, 
				draw_abstract_matching		= 0x00001000
		};	
		
		recognized_char_group recognize( const CharImage &char_scan, float base_line_pos, float reference_height, float angle );
		abstract_character vectorize( const CharImage &char_scan, float base_line_pos, float reference_height, float angle );
		float get_max_height( const CharImage &char_scan, float angle );
		void build_cssg();
		bool get_cross_point( const Segimage::point s, Segimage::point &e, float angle );
		void set_draw_flag( drawing_flags flag, bool state );
		void next_border_list( bool next );
		void mark_next_cs( bool next );
		void change_line_thickness( bool next );
		void makeSnapshot();
		void replace_char();
		void append_variant_char();

	protected:
		void paintEvent( QPaintEvent *e );
		void mouseMoveEvent( QMouseEvent *e );
		void keyPressEvent( QKeyEvent *e );
		
	private:
		Image( const Image & );				// 构造函数
		Image& operator=( const Image & );	// 复制操作符

		static void drawFilledCircle( QPainter &p, const QPen &pen, int x, int y, int diameter, bool save_state );
		static void setFillParameter( QPainter &p, const QPen &pen );
		static void drawFilledCircleFast( QPainter &p, int x, int y, int diameter );
		void drawRecognitionState( QPixmap &pix, float factor );
		double direction( Segimage::point p );
		double calc_dang( double prev, double curr );
		bool need_no_smoothing( ringlist_iterator< Segimage::point > it );
		void smooth_points( ringlist_iterator< Segimage::point > first, ringlist_iterator< Segimage::point > last, int num_points );
		bool opposite_same_direction( ringlist_iterator< Segimage::point > &start_point );
		int construct_sequence( ringlist_iterator< Segimage::point > &start_point, Segimage &simage, Segimage::cs_sequence &seq );
		void detect_singular_region( Segimage::cs_sequence_start &csss, Segimage &simage, list< Segimage::singularpoint > &spl );
		void clear();
		float get_ratio();
		int get_dpi_ratio( float dpi, float target_size_cm, bool is_height );
	
		// debug view parameters
		unsigned int draw_flags;	// 画图标识
		int border_list_number;		// 边界列表数目
		int match_char_pos;	
		int mark_cs;
		int pen_size;				// 画笔大小

		double avg_line_thickness;	// 字符线条的平均粗细
		CharImage scan;				// 扫描进的字符
		CharImage scan_bw;			// 二值化图像

		Segimage *segimage;			// 字符的分割和交叉部分
		Segimage::border_lists bl;			// 边界列表
		list<Segimage::cs_sequence> cssl;	// 交叉序列列表
		list<Segimage::singularpoint> spl;	// 孤立点列表

		character *skeleton;				// 细化后的字符
		abstract_character *abstract_char;	// 归一化后的骨架
		recognized_char_group char_group;	// 已经识别的字符组
		KognitionApp *app;
	signals:
		void setStatusMsg( const QString &str );
};

inline void Image::setFillParameter( QPainter &p, const QPen &pen )
{
	p.setPen( pen );
	p.setBrush( QBrush( pen.color() ) );
}

inline void Image::drawFilledCircleFast( QPainter &p, int x, int y, int diameter )
{
	p.drawEllipse( x - diameter/2, y - diameter/2, diameter, diameter );
}

inline bool Image::need_no_smoothing( ringlist_iterator< Segimage::point > it )
{
	Segimage::point &p = *it;
	Segimage::point &p_next = *( ++it );
	return ( p.dang <= 0 && p_next.dang <= 0 ) || ( p.dang >= 0 && p_next.dang >= 0 );
}

inline float Image::get_ratio()
{	
	float factor_x = static_cast<float>( width() ) / scan.width();
	float factor_y = static_cast<float>( height() ) / scan.height();
	return ( factor_x < factor_y ) ? factor_x : factor_y;
}

inline int Image::get_dpi_ratio( float dpi, float target_size_cm, bool is_height )
{
	int dots = static_cast< int >( target_size_cm*dpi / 2.54 );
	if ( is_height )
		return dots / scan.height();
	else
		return dots / scan.width();
}

#endif