漫谈WinCE的手写识别技术(二)
//========================================================================
//TITLE:
// 漫谈WinCE的手写识别技术(二)
//AUTHOR:
// norains
//DATE:
// Thursday 25-January -2007
//Environment:
// EVC4.0 + Standard SDK
//========================================================================
在第一章的时候,已经介绍了识别的一般性过程,对于实际运用来说,是完全可行的;但从便利性角度出发,却不免显得烦琐:每次输入笔画都需留意点阵是否屏幕坐标系,每次读取返回的字符总要分配内存然后获取等等,诸如总总,代码写一次还好,如果多处运用多次编写多方维护,实在不是一件快乐的事情.
而我,最讨厌做复杂又要花费脑筋的东东;所以,为了让自己感觉得写代码是一件快乐的事情,自己又很高兴地将识别过程封装为一个类.至于是否达到简便的效果,不敢祈求大家苟同,只愿自己舒坦即可.
//////////////////////////////////////////////////////////////////////
// Recognizer.h: interface for the CRecognizer class. ////////////////////////////////////////////////////////////////////////#ifndef RECOGNIZER_H#define RECOGNIZER_H//===========================================================================//Include file#include "recog.h"//=====================================================================================//Choose the build type for the recognizing function//--------------------------------------------------------------------------#define RECOGNIZE_FUNCTION_FROM_DLL//#define RECOGNIZE_FUNCTION_FROM_LIB#ifndef RECOGNIZE_FUNCTION_FROM_LIB #ifndef RECOGNIZE_FUNCTION_FROM_DLL #define RECOGNIZE_FUNCTION_FROM_DLL #endif#endif#ifdef RECOGNIZE_FUNCTION_FROM_DLL #define RECOGNIZE_DLL_PATH TEXT("/WINDOWS/hwxcht.dll")#endif//=====================================================================================//-----------------------------------------------------------------------------------//The data type//The scale type for the coordinateenum ScaleType{
SCALE_APPWND, SCALE_SCREEN
};//------------------------------------------------------------------------------class CRecognizer {public: BOOL InputStroke(POINT *lpPnt, int iCount, ScaleType scale); CRecognizer(); virtual ~CRecognizer(); int GetCharacter(WCHAR *pWchar, int iCount); BOOL EndRecognize(); BOOL BeginRecognize(); BOOL Initialize(HWND hWnd,const RECT *prcWnd,ScaleType scale);protected: HRC m_hrc; HWXGUIDE m_hwxGuide; HWND m_hWndRecog; ALC m_alc;#ifdef RECOGNIZE_FUNCTION_FROM_DLL typedef BOOL (WINAPI *DLL_HWXCONFIG)(void); typedef HRC (WINAPI *DLL_HWXCREATE)(HRC = NULL); typedef BOOL (WINAPI *DLL_HWXSETGUIDE)(HRC ,HWXGUIDE*); typedef BOOL (WINAPI *DLL_HWXALCVALID)(HRC,ALC); typedef BOOL (WINAPI *DLL_HWXALCPRIORITY)(HRC,ALC); typedef BOOL (WINAPI *DLL_HWXSETCONTEXT)(HRC,WCHAR); typedef BOOL (WINAPI *DLL_HWXINPUT)(HRC,POINT*,UINT, DWORD); typedef BOOL (WINAPI *DLL_HWXENDINPUT)(HRC); typedef BOOL (WINAPI *DLL_HWXPROCESS)(HRC); typedef INT (WINAPI *DLL_HWXRESULTSAVAILABLE)(HRC); typedef INT32 (WINAPI *DLL_HWXGETRESULTS)(HRC, UINT, UINT, UINT, HWXRESULTS*); typedef BOOL (WINAPI *DLL_HWXDESTROY)(HRC); DLL_HWXCONFIG HWXCONFIG; DLL_HWXCREATE HWXCREATE; DLL_HWXSETGUIDE HWXSETGUIDE; DLL_HWXALCVALID HWXALCVALID; DLL_HWXALCPRIORITY HWXALCPRIORITY; DLL_HWXSETCONTEXT HWXSETCONTEXT; DLL_HWXINPUT HWXINPUT; DLL_HWXPROCESS HWXPROCESS; DLL_HWXRESULTSAVAILABLE HWXRESULTSAVAILABLE; DLL_HWXGETRESULTS HWXGETRESULTS; DLL_HWXDESTROY HWXDESTROY; DLL_HWXENDINPUT HWXENDINPUT;#endif //RECOGNIZE_FUNCTION_FROM_DLL#ifdef RECOGNIZE_FUNCTION_FROM_LIB #define HWXCONFIG(void) HwxConfig(void) #define HWXCREATE(hrc) HwxCreate(hrc) #define HWXSETGUIDE(hrc,lpGuide) HwxSetGuide(hrc,lpGuide) #define HWXALCVALID(hrc,alc) HwxALCValid(hrc,alc) #define HWXALCPRIORITY(hrc,alc) HwxALCPriority(hrc,alc) #define HWXSETCONTEXT(hrc,wContext) HwxSetContext(hrc,wContext) #define HWXINPUT(hrc,lppnt,upoints,timestamp) HwxInput(hrc,lppnt,upoints,timestamp) #define HWXPROCESS(hrc) HwxProcess(hrc) #define HWXRESULTSAVAILABLE(hrc) HwxResultsAvailable(hrc) #define HWXGETRESULTS(hrc,cAlt,iFirst,cBoxRes,rgBoxResults) HwxGetResults(hrc,cAlt,iFirst,cBoxRes,rgBoxResults) #define HWXDESTROY(hrc) HwxDestroy(hrc) #define HWXENDINPUT(hrc) HwxEndInput(hrc)#endif //RECOGNIZE_FUNCTION_FROM_LIB};//============================================================================================#endif // !defined RECOGNIZER_H
//////////////////////////////////////////////////////////////////////// Recognizer.cpp: implementation of the CRecognizer class. ////////////////////////////////////////////////////////////////////////#include "stdafx.h"#include "Recognizer.h"//-------------------------------------------------------------------//Macro define//The default value of hwxGuide#define DEFAULT_HWXGUIDE_CHORZBOX 1#define DEFAULT_HWXGUIDE_CVERTBOX 1#define DEFAULT_HWXGUIDE_CXOFFSET 1#define DEFAULT_HWXGUIDE_CYOFFSET 1//The default value of ALC#define DEFAULT_ALC ALC_KANJI_ALL//--------------------------------------------------------------------//////////////////////////////////////////////////////////////////////// Construction/Destruction//////////////////////////////////////////////////////////////////////CRecognizer::CRecognizer(){ m_alc = NULL; m_hrc = NULL; m_hWndRecog = NULL; memset(&m_hwxGuide,0,sizeof(m_hwxGuide));}CRecognizer::~CRecognizer(){}//-----------------------------------------------------------------------//Descriptiong:// Initialize the recognizer////Parameter:// hWnd: [in] The handle of window to be recognized// rcWnd: [in] The window area to be recognized// scale: [in] The scale base of prcWnd point//-----------------------------------------------------------------------BOOL CRecognizer::Initialize(HWND hWnd,const RECT *prcWnd,ScaleType scale){ m_hWndRecog = hWnd; m_alc = DEFAULT_ALC;
RECT rcWnd = {0};
RECT rcWnd switch(scale) { case SCALE_APPWND: { rcWnd = *prcWnd; rcWnd.left *= 4; rcWnd.right *= 4; rcWnd.top *= 4; rcWnd.bottom *= 4; MapWindowPoints(hWnd,HWND_DESKTOP,(LPPOINT)(&rcWnd),(sizeof(RECT)/sizeof(POINT))); break;
} case SCALE_SCREEN: { rcWnd = *prcWnd; break; } } m_hwxGuide.cHorzBox = DEFAULT_HWXGUIDE_CHORZBOX; m_hwxGuide.cVertBox = DEFAULT_HWXGUIDE_CVERTBOX; m_hwxGuide.xOrigin = rcWnd.left; m_hwxGuide.yOrigin = rcWnd.top; m_hwxGuide.cxBox = rcWnd.right - rcWnd.left; m_hwxGuide.cyBox = rcWnd.bottom - rcWnd.top; m_hwxGuide.cxOffset = DEFAULT_HWXGUIDE_CXOFFSET; m_hwxGuide.cyOffset = DEFAULT_HWXGUIDE_CYOFFSET; m_hwxGuide.cxWriting = (rcWnd.right - rcWnd.left) - m_hwxGuide.cxOffset * 2; m_hwxGuide.cyWriting = (rcWnd.bottom - rcWnd.top) - m_hwxGuide.cyOffset * 2; m_hwxGuide.nDir = HWX_HORIZONTAL;#ifdef RECOGNIZE_FUNCTION_FROM_DLL HINSTANCE hInstDll; hInstDll = LoadLibrary(RECOGNIZE_DLL_PATH); if(hInstDll != NULL) { HWXCONFIG = (DLL_HWXCONFIG) GetProcAddress(hInstDll,TEXT("HwxConfig")); HWXCREATE = (DLL_HWXCREATE) GetProcAddress(hInstDll,TEXT("HwxCreate")); HWXSETGUIDE = (DLL_HWXSETGUIDE) GetProcAddress(hInstDll,TEXT("HwxSetGuide")); HWXALCVALID = (DLL_HWXALCVALID) GetProcAddress(hInstDll,TEXT("HwxALCValid")); HWXALCPRIORITY = (DLL_HWXALCPRIORITY) GetProcAddress(hInstDll,TEXT("HwxALCPriority")); HWXSETCONTEXT = (DLL_HWXSETCONTEXT) GetProcAddress(hInstDll,TEXT("HwxSetContext")); HWXINPUT = (DLL_HWXINPUT) GetProcAddress(hInstDll,TEXT("HwxInput")); HWXPROCESS = (DLL_HWXPROCESS) GetProcAddress(hInstDll,TEXT("HwxProcess")); HWXRESULTSAVAILABLE = (DLL_HWXRESULTSAVAILABLE) GetProcAddress(hInstDll,TEXT("HwxResultsAvailable")); HWXGETRESULTS = (DLL_HWXGETRESULTS) GetProcAddress(hInstDll,TEXT("HwxGetResults")); HWXDESTROY = (DLL_HWXDESTROY) GetProcAddress(hInstDll,TEXT("HwxDestroy")); HWXENDINPUT = (DLL_HWXENDINPUT) GetProcAddress(hInstDll,TEXT("HwxEndInput")); } else { return FALSE; }#endif //RECOGNIZE_FUNCTION_FROM_DLL if(HWXCONFIG() == FALSE) { return FALSE; } return TRUE;}//-----------------------------------------------------------------------//Descriptiong:// Begin recognizing//-----------------------------------------------------------------------BOOL CRecognizer::BeginRecognize(){ BOOL bRes = FALSE; m_hrc = HWXCREATE(); if(m_hrc == NULL) { goto END; } bRes = HWXSETGUIDE(m_hrc,&m_hwxGuide); if(bRes == FALSE) { goto END; } bRes = HWXALCVALID(m_hrc,m_alc); if(bRes == FALSE) { goto END; } bRes = TRUE;END: return bRes;}//-----------------------------------------------------------------------//Descriptiong:// End recognizing//-----------------------------------------------------------------------BOOL CRecognizer::EndRecognize(){ BOOL bRes = FALSE; //Destroy the recognizer if(HWXDESTROY(m_hrc) == FALSE) { goto END; } bRes = TRUE;END: return bRes;}//-----------------------------------------------------------------------//Descriptiong:// Get the character////Parameters:// pWchar: [out] The character get to be stored// iCount: [in] The number of pWchar ////Return Values:// 0: Failed// >0: The number of the characters to return//-----------------------------------------------------------------------int CRecognizer::GetCharacter(WCHAR *pWchar, int iCount){ int iGetNum = 0; int i = 0; HWXRESULTS *phwxResults; //Because each HWXRESULTS after the first one could store two characters, //so only allocate (iCount / 2 + 1) int iNum = iCount / 2 + 1; phwxResults = new HWXRESULTS[iNum]; memset(phwxResults,0,iNum * sizeof(HWXRESULTS)); //End the input if(HWXENDINPUT(m_hrc) == FALSE) { goto END; } //Analyze the information if(HWXPROCESS(m_hrc) == FALSE) { goto END; } //Get the character from recognizer if(HWXGETRESULTS(m_hrc,iCount,0,1,phwxResults) == FALSE) { goto END; } //Set the character to the stored buffer for(i = 0; i < iNum; i++) { if(i == 0) { if(phwxResults[i].rgChar[0] != 0) { pWchar[iGetNum ++] = phwxResults[i].rgChar[0]; } else { break; } } else { //The indxBox member also store the character if(phwxResults[i].indxBox != 0) { pWchar[iGetNum ++] = phwxResults[i].indxBox ; } else { break; } if(phwxResults[i].rgChar[0] != 0) { pWchar[iGetNum ++] = phwxResults[i].rgChar[0]; } else { break; } } }END: if(phwxResults != NULL) { delete [] phwxResults; } return iGetNum;}//-----------------------------------------------------------------------//Descriptiong:// Input the stroke////Parameter:// lpPnt: [in] Pointer to the stroke POINT// iCount: [in] The count of the lpPnt// scale: [in] The scale base of lpPnt//-----------------------------------------------------------------------BOOL CRecognizer::InputStroke(POINT *lpPnt, int iCount, ScaleType scale){ BOOL bRes = FALSE; int i = 0; POINT *pt; pt = new POINT[iCount]; if(pt == NULL) { goto END; } for(i = 0; i < iCount; i++) { pt[i] = lpPnt[i]; if(scale == SCALE_APPWND) { //Convert to the screen scale pt[i].x *= 4; pt[i].y *= 4; MapWindowPoints(m_hWndRecog, HWND_DESKTOP, &pt[i], 1); } } //Input stroke bRes = HWXINPUT(m_hrc,pt,iCount,0); if(bRes == FALSE) { goto END; } bRes = TRUE;END: if(pt != NULL) { delete [] pt; } return bRes;} 不知道大家看到这段代码有什么感觉,反正我是挺高兴的,因为让我从繁琐的识别过程中脱离出来.
关于代码,也许最让人疑惑的可能是这两个宏:RECOGNIZE_FUNCTION_FROM_DLL,RECOGNIZE_FUNCTION_FROM_LIB.
顾名思义,RECOGNIZE_FUNCTION_FROM_DLL表明识别函数调用是来源于动态链接库(DLL),同理,RECOGNIZE_FUNCTION_FROM_LIB则是编译的时候链接到lib库.为什么需要定义这两个宏呢?因为在标准的SDK下,如果直接包含"recog.h"后调用相关识别函数,是会报link错误.因为标准的SDK是不包含任何手写识别组件的.从调试的便利性来说,这时候如果只拷贝识别库到模拟器就可以顺利测试程序,绝对比重新定制一个包含手写识别引擎的系统要来得方便.
在示例代码中,因为是识别繁体中文,所以包含的动态链接库为:hwxcht.dll.如果需要识别其它文字,则只要更改该动态链接库名称即可.当然,还要更改DEFAULT_ALC宏,这个宏定义了识别的范围.
因为示例代码中的识别函数全部是宏定义,具体意义根据函数的来源而不同,所以RECOGNIZE_FUNCTION_FROM_DLL和RECOGNIZE_FUNCTION_FROM_LIB同一时间只能定义一个.如果两个都定义,毫无疑问,出错!^_^
最后,用伪代码做范例说明如何使用该封装类,以此做本章结尾:
CRecognizer recog; Rect rcWnd; /*rcWnd 获取应用窗口hWnd的大小*/ //初始化 //直接赋值窗口坐标,函数体内部会根据标志直接转换为屏幕坐标 recog.Initialize(hWnd,&rcWnd,SCALE_APPWND); //开始识别 recog.BeginRecognize(); POINT pt[200]; int iCount = 0; /*获取笔画坐标给pt,坐标的数量储存在iCount中*/ //将笔画点阵传送给识别引擎 //如果有多个笔画,则每个笔画都需要调用该函数进行传入 recog.InputStroke(pt,iCount,SCALE_APPWND); //获取十个最接近的字符,iReturn是实际返回的字符数 WCHAR wChar[10]; int iReturn = recog.GetCharacter(wChar,10); //结束识别 recog.EndRecognize(); /*如果
