本文實例講述了基于Directx MMX 編寫的實現圖像灰度處理的方法，要編譯此程序需DirectX SDK5.0，代碼中所需要的ddutil.h與ddutil.cpp文件,請自行下載加入工程。在WindowNT4.0+SP3環境中編譯通過，代碼已經過整理，包含有注釋。如下所示：
#include <windows.h>#include <windowsx.h>#include <stdio.h>#include <ddraw.h>#include <math.h>#include "ddutil.h"#define MEAN_GRAY 0//平均值法#define MAXIMUM_GRAY 1//最大值法#define WEIGHT_GRAY 2//加權平均值法#define TITLE "灰度轉換" //窗口標題#define CLASSNAME "Gray" //窗口類名#define WIDTH 640#define HEIGHT 480#define COLORS 8#define STEP 1#define SCANLINE 16HINSTANCE hInst; //應用程序實例句柄HWND hWndMain; //主窗口句柄LPDIRECTDRAW lpDD; // DirectDraw對象LPDIRECTDRAWSURFACE lpDDSPrimary; // 主頁面LPDIRECTDRAWSURFACE lpDDSBack; // 后臺緩沖區LPDIRECTDRAWSURFACE lpDDSPic1; // 離屏頁面1LPDIRECTDRAWPALETTE lpDDPal; // 調色板BOOL bActive; // 應用程序是否活躍?int Key=0;bool Contrast=false;bool Gray=false;//函數聲明void FreeObjects( void );BOOL InitDDraw(void);BOOL InitPalette(void);BOOL InitSurfaces(void);void UpdateFrame(void);void MakeRect(RECT *rect, long left, long top, long right, long bottom);void IncreaseContrast(BYTE *pByte,const int Low,const int Hight, const float Grad){ if(*pByte<=Low) *pByte=0; else if((Low<*pByte)&&(*pByte<Hight)) *pByte=(BYTE)((*pByte-Low)/Grad); else *pByte=255;}void ChangeContrast(int nDelta){ LPPALETTEENTRY Pal = (LPPALETTEENTRY) LocalAlloc( LPTR, sizeof( PALETTEENTRY ) * 256 ); //獲取調色板 lpDDPal->GetEntries(0,0,256,Pal); int Low,High; float Grad; for(int i=0; i<256; i++) { if(nDelta>=0) { Low=0+nDelta; High=255-nDelta; Grad=((float)(High-Low))/255; IncreaseContrast(&Pal[i].peRed ,Low,High,Grad); IncreaseContrast(&Pal[i].peGreen ,Low,High,Grad); IncreaseContrast(&Pal[i].peBlue ,Low,High,Grad); } else { Pal[i].peRed=(BYTE)((int)(Pal[i].peRed/Grad))-nDelta; Pal[i].peGreen=(BYTE)((int)(Pal[i].peGreen/Grad))-nDelta; Pal[i].peBlue=(BYTE)((int)(Pal[i].peBlue/Grad))-nDelta; } } //更新調色板 lpDDPal->SetEntries(0,0,256,Pal);}//灰度轉換函數--本程序的關鍵//函數：ConvertToGrayScale//參數：Method為轉換灰度的方式，值可為：// MAXIMUM_GRAY=最大值法,MEAN_GRAY=平均值法,// WEIGHT_GRAY=加權平均值法// Color目前只能為8即只能處理8位調色板方式//返值：無void ConvertToGrayScale(unsigned short Method,unsigned short Color){ BYTE Convert; int i; switch(Color) { case 8: LPPALETTEENTRY Pal = (LPPALETTEENTRY) LocalAlloc( LPTR, sizeof( PALETTEENTRY ) * 256 ); //獲取調色板 lpDDPal->GetEntries(0,0,256,Pal); switch(Method) { case MAXIMUM_GRAY: //最大值法轉換 for(i=0; i<256; i++) { //計算的公式為：R=G=B=max(R,G,B) Convert=( max(max(Pal[i].peRed ,Pal[i].peGreen),Pal[i].peBlue)); Pal[i].peRed=Pal[i].peGreen=Pal[i].peBlue=Convert; } break; case MEAN_GRAY: //平均值法轉換 for(i=0; i<256; i++) { //計算的公式為：R=G=B=(R+G+B)/3 Convert=((Pal[i].peRed +Pal[i].peGreen+Pal[i].peBlue)/3); Pal[i].peRed=Pal[i].peGreen=Pal[i].peBlue=Convert; } break; case WEIGHT_GRAY: //加權平均值法轉換 for(i=0; i<256; i++) { //計算的公式為：R=G=B=(R*0.3+G*0.59+B*0.11) //為不使用浮點乘法，現公式為： //R=G=B=(R*3+G*6+B)/10 //些許的誤差可以不計 Convert=( Pal[i].peRed * 3 + Pal[i].peGreen *6 + Pal[i].peBlue ) / 10; Pal[i].peRed=Pal[i].peGreen=Pal[i].peBlue=Convert; } break; } //更新調色板 lpDDPal->SetEntries(0,0,256,Pal); break; }}//**********************************//函數：FreeObject//功能：釋放所有DirectDraw對象void FreeObjects( void ){ if( lpDD != NULL )//釋放DirectDraw對象 { if( lpDDSPrimary != NULL )//釋放主頁面 { lpDDSPrimary->Release(); lpDDSPrimary = NULL; } if( lpDDSPic1 != NULL )//釋放離屏頁面1 { lpDDSPic1->Release(); lpDDSPic1 = NULL; } if( lpDDPal != NULL )//釋放調色板 { lpDDPal->Release(); lpDDPal = NULL; } lpDD->Release(); lpDD = NULL; }} //************************************//函數：RestoreAll//功能：頁面丟失后，恢復頁面內存HRESULT RestoreAll( void ){ HRESULT ddrval; //恢復主頁面，這也將恢復換頁鏈中的所有頁面 ddrval = lpDDSPrimary->Restore(); //恢復離屏頁面 ddrval = lpDDSPic1->Restore(); //重新繪制頁面圖象 InitSurfaces(); return ddrval;}//**************************************//函數：WindowProc//功能：主窗口的消息處理過程LRESULT CALLBACK WinProc( HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam ){ switch( message ) { case WM_SETCURSOR: SetCursor(NULL); return TRUE; case WM_ACTIVATEAPP://應用程序激活消息 bActive = wParam; break; case WM_KEYDOWN://擊鍵消息 switch( wParam ) { case VK_ESCAPE: PostMessage(hWnd, WM_CLOSE, 0, 0); break; case VK_F1: Gray=true; Key=MEAN_GRAY; InitPalette(); break; case VK_F2: Gray=true; Key=MAXIMUM_GRAY; InitPalette(); break; case VK_F3: Gray=true; Key=WEIGHT_GRAY; InitPalette(); break; case VK_F4: Gray=false; Key=0; InitPalette(); break; case VK_F5: Contrast=!Contrast; if(false==Contrast) { InitPalette(); } break; case VK_F6: break; } break; case WM_DESTROY://銷毀窗口消息 FreeObjects(); PostQuitMessage(0); break; } //調用缺省的過程處理過程 return DefWindowProc(hWnd, message, wParam, lParam);}//*********************************//函數：InitWindow()//功能：創建主窗口。BOOL InitWindow( HINSTANCE hInstance, int nCmdShow ){ WNDCLASS wc; //窗口類結構 //填充窗口類結構 wc.style = 0; wc.lpfnWndProc = WinProc; wc.cbClsExtra = 0; wc.cbWndExtra = 0; wc.hInstance = hInstance; wc.hIcon = LoadIcon( hInstance, IDI_APPLICATION ); wc.hCursor = LoadCursor( NULL, IDC_ARROW ); wc.hbrBackground = (HBRUSH)GetStockObject(BLACK_BRUSH);//選擇黑色刷做為窗口背景 wc.lpszMenuName = NULL; wc.lpszClassName = CLASSNAME; //注冊窗口類 RegisterClass( &wc ); //創建主窗口 hWndMain= CreateWindowEx( 0, CLASSNAME, //窗口的類名稱，必須與上面的wc.lpszClassName一致 TITLE, //窗口的標題名 WS_POPUP, 0, 0, GetSystemMetrics( SM_CXSCREEN ), GetSystemMetrics( SM_CYSCREEN ), NULL, NULL, hInstance, NULL ); if( !hWndMain ) return FALSE; //顯示并更新窗口 ShowWindow( hWndMain, nCmdShow ); return TRUE;}//*********************************//函數：InitDDraw()//功能：初始化DirectDraw環境，創建換頁鏈（主頁面，一個后臺緩沖區）// 以及創建一個定時器。BOOL InitDDraw(void){ DDSURFACEDESC ddsd; DDSCAPS ddscaps; HRESULT ddrval; //創建DirectDraw對象 ddrval = DirectDrawCreate( NULL, &lpDD, NULL ); if( ddrval != DD_OK ) return FALSE; //取得全屏獨占模式 ddrval = lpDD->SetCooperativeLevel( hWndMain, DDSCL_EXCLUSIVE | DDSCL_FULLSCREEN ); if( ddrval != DD_OK ) return FALSE; //設置顯示器顯示模式為640x480x8 ddrval = lpDD->SetDisplayMode( WIDTH, HEIGHT, COLORS); if( ddrval != DD_OK ) return FALSE; //填充換頁鏈結構 ddsd.dwSize = sizeof( ddsd ); ddsd.dwFlags = DDSD_CAPS | DDSD_BACKBUFFERCOUNT; ddsd.ddsCaps.dwCaps = DDSCAPS_PRIMARYSURFACE | DDSCAPS_FLIP | DDSCAPS_COMPLEX; //后臺緩沖區數量為1 ddsd.dwBackBufferCount = 1; //創建換頁鏈，包括了主頁面及其后臺緩沖區 ddrval = lpDD->CreateSurface( &ddsd, &lpDDSPrimary, NULL ); if( ddrval != DD_OK ) return FALSE; //獲得指向后臺緩沖區的頁面指針 ddscaps.dwCaps = DDSCAPS_BACKBUFFER; ddrval = lpDDSPrimary->GetAttachedSurface(&ddscaps, &lpDDSBack); if( ddrval != DD_OK ) return FALSE; //創建離屏頁面 ZeroMemory(&ddsd, sizeof(ddsd)); ddsd.dwSize = sizeof(ddsd); ddsd.dwFlags = DDSD_CAPS | DDSD_HEIGHT |DDSD_WIDTH; ddsd.ddsCaps.dwCaps = DDSCAPS_OFFSCREENPLAIN; ddsd.dwWidth = WIDTH; ddsd.dwHeight = HEIGHT; if (lpDD->CreateSurface(&ddsd, &lpDDSPic1, NULL) != DD_OK) return FALSE; //調用頁面初始化函數 if( !InitSurfaces() ) return FALSE; return TRUE;}//**********************************//函數：WinMain()//功能：應用程序入口int PASCAL WinMain( HINSTANCE hInstance, HINSTANCE hPrevInstance,LPSTR lpCmdLine, int nCmdShow){ MSG msg; hInst=hInstance; //初始化主窗口 if (!InitWindow( hInstance, nCmdShow)) return FALSE; //初始化DirectDraw環境 if (!InitDDraw()) { MessageBox(hWndMain, "初始化DirectDraw過程中出錯！", "Error", MB_OK); FreeObjects(); DestroyWindow(hWndMain); return FALSE; } //進入消息循環 while(1) { if(PeekMessage(&msg, NULL, 0, 0, PM_NOREMOVE)) { if(!GetMessage(&msg, NULL, 0, 0 )) return msg.wParam; TranslateMessage(&msg); DispatchMessage(&msg); } else if(bActive) { UpdateFrame(); } else WaitMessage(); } return msg.wParam;} BOOL InitPalette(void){ //從磁盤文件中載入調色板 lpDDPal = DDLoadPalette(lpDD, "back.bmp"); //將調色板設置給主頁面 if (lpDDPal) { lpDDSPrimary->SetPalette( lpDDPal ); return TRUE; } return FALSE;}//****************************//函數：InitSurfaces()//功能：初始化頁面圖象BOOL InitSurfaces( void ){ HBITMAP hbm; InitPalette(); //從磁盤文件中將我們所需要的圖象載入到一個hbm位圖對象中 hbm = (HBITMAP)LoadImage(hInst, "back.bmp", IMAGE_BITMAP, 0, 0, LR_CREATEDIBSECTION|LR_LOADFROMFILE); if (hbm == NULL) return FALSE; DDCopyBitmap(lpDDSPic1, hbm, 0, 0, WIDTH, HEIGHT); //釋放hbm位圖對象 DeleteObject(hbm); return TRUE;}//更新屏幕void UpdateFrame( void ){ HRESULT ddrval; //計算刷新率 static int fps=0, frame=0, nt=0, ot=0; frame++; nt=timeGetTime(); if (nt > ot+1000) { ot=nt; fps=frame; frame=0; } //清屏后臺緩沖區 DDBLTFX ddBltFx; ddBltFx.dwSize = sizeof(DDBLTFX); ddBltFx.dwFillColor = DDColorMatch(lpDDSBack, RGB(0,0,0)); lpDDSBack->Blt(NULL, NULL, NULL, DDBLT_WAIT | DDBLT_COLORFILL, &ddBltFx); //調用灰度的實現函數 if(true==Gray) { ConvertToGrayScale(Key,COLORS); Gray=false; } //增加對比度 if(true==Contrast) { ChangeContrast(2); } RECT srect, drect; MakeRect(&srect, 0, 0, WIDTH, HEIGHT); MakeRect(&drect, 0, 0, WIDTH, HEIGHT); //將背景圖象Blit到后臺緩沖區 lpDDSBack->Blt(&drect, lpDDSPic1, &srect, DDBLT_WAIT, NULL); //打印刷新率fps HDC hdc; char temp[50]; lpDDSBack->GetDC(&hdc); SetBkMode(hdc, TRANSPARENT); SetTextColor(hdc, RGB(0,255,255)); sprintf(temp, "fps=%d", fps); TextOut(hdc, 0, 0, temp, strlen(temp)); sprintf(temp,"圖象特效----灰度轉換"); TextOut(hdc, 30, 400, temp, strlen(temp)); lpDDSBack->ReleaseDC(hdc); // 換頁 while( 1 ) { ddrval = lpDDSPrimary->Flip( NULL, DDFLIP_WAIT );//調用換頁函數 if( ddrval == DD_OK )//成功則退出while循環 break; else if( ddrval == DDERR_SURFACELOST )//如果頁面丟失，則恢復頁面，再繼續while循環 RestoreAll(); else break; }}void MakeRect(RECT *rect, long left, long top, long right, long bottom){ rect->left=left; rect->top=top; rect->right=right; rect->bottom=bottom;}感興趣的朋友可以調試運行一下本文實例，相信會對大家進行C++項目開發起到一定的幫助作用。
新聞熱點
疑難解答
圖片精選
