- Visual C++數字圖像模式識別典型案例詳解
- 馮偉興 梁洪 王臣業編著
- 812字
- 2018-12-31 19:39:09
5.4.2 人臉識別與分割
編程實現
[1] 在視圖類里添加消息映射函數Onboundary()以實現輪廓提取。Onboundary()函數代碼如代碼5-5所示。
代碼5-5 Onboundary()函數
void CDemoView::Onboundary()
{
CDemoDoc ＊pDoc=GetDocument();
ImageDib ＊pDib=pDoc->GetPDib();
int i,j,thd;
CSize size=pDib->GetDimensions();
int lineByte=(size.cx+3)/4＊4;
long pixel_scales=0;
for(i=0;i<size.cx;i++){
for(j=0;j<size.cy;j++){
pixel_scales+=＊(pDib->m_pImgData+j＊lineByte+i);
}
}
thd=pixel_scales/(size.cx＊size.cy);
GrayTrans graytrans(size,pDib->m_nBitCount, pDib->m_lpColorTable, pDib->
m_pImgData);
graytrans.Binary(thd); //調用Binary()對圖像進行二值化
//建立一個新視圖，顯示分割結果
CMainFrame＊ pFrame = (CMainFrame ＊)(AfxGetApp()->m_pMainWnd);
pFrame->SendMessage(WM_COMMAND, ID_FILE_NEW);
CDemoView＊ pView=(CDemoView＊)pFrame->MDIGetActive()->GetActiveView();
CDemoDoc＊ pDocNew=pView->GetDocument();
ImageDib ＊dibNew=pDocNew->GetPDib();
dibNew->ReplaceDib(graytrans.GetDimensions(),graytrans.m_nBitCountOut,
graytrans.m_lpColorTableOut, graytrans.m_pImgDataOut);
pView->OnInitialUpdate();
pDocNew->SetModifiedFlag(TRUE);
pDocNew->UpdateAllViews(pView);
}
void CDemo1View::Onboundary()
{
CDemo1Doc ＊pDoc=GetDocument();
ImageDib ＊pDib=pDoc->GetPDib();
//只處理灰度圖像
if(pDib->m_nBitCount!=8){
::MessageBox(0, "只處理灰度圖像", MB_OK,0);
return ;
}
int i,j,thd;
CSize size=pDib->GetDimensions();
int lineByte=(size.cx+3)/4＊4;
long pixel_scales=0;
for(i=0;i<size.cx;i++){
for(j=0;j<size.cy;j++){
pixel_scales+=＊(pDib->m_pImgData+j＊lineByte+i);
}
}
thd=pixel_scales/(size.cx＊size.cy);
GrayTrans graytrans(size,pDib->m_nBitCount, pDib->m_lpColorTable, pDib->
m_pImgData);
//調用Binary()對圖像進行二值化
graytrans.BinaryImage(thd);
//建立一個新視圖，顯示分割結果
CMainFrame＊ pFrame = (CMainFrame ＊)(AfxGetApp()->m_pMainWnd);
pFrame->SendMessage(WM_COMMAND, ID_FILE_NEW);
CDemo1View＊ pView=(CDemo1View＊)pFrame->MDIGetActive()->GetActiveView();
CDemo1Doc＊ pDocNew=pView->GetDocument();
ImageDib ＊dibNew=pDocNew->GetPDib();
dibNew->ReplaceDib(graytrans.GetDimensions(),graytrans.m_nBitCountOut,gray
trans.m_lpColorTableOut, graytrans.m_pImgDataOut);
pView->OnInitialUpdate();
pDocNew->SetModifiedFlag(TRUE);
pDocNew->UpdateAllViews(pView);
}
[2] 上述代碼中調用了GrayTrans類中的BinaryImage ()函數，已進行圖像的二值化處理，其具體代碼如代碼5-6所示。
代碼5-6 BinaryImage()函數
void GrayTrans::BinaryImage(int threshold)
{
//對于灰度圖像
if(m_nBitCount==8){
//釋放舊的輸出圖像數據及顏色表緩沖區
if(m_pImgDataOut!=NULL){
delete []m_pImgDataOut;
m_pImgDataOut=NULL;
}
if(m_lpColorTableOut!=NULL){
delete []m_lpColorTableOut;
m_lpColorTableOut=NULL;
}
//輸出圖像的每像素位數、顏色表長度
m_nBitCountOut=m_nBitCount;
m_nColorTableLengthOut=ComputeColorTabalLength(m_nBitCountOut);
//申請輸出圖像顏色表緩沖區，并將輸入圖像顏色表復制至輸出圖像顏色表中
m_lpColorTableOut=new RGBQUAD[m_nColorTableLengthOut];
memcpy(m_lpColorTableOut,m_lpColorTable,sizeof(RGBQUAD)＊m_
nColorTableLengthOut);
//輸出圖像的寬高，與輸入圖像相等
m_imgWidthOut=m_imgWidth;
m_imgHeightOut=m_imgHeight;
//圖像每行像素所占字節數，輸入圖像與輸出圖像每行像素所占字節數相等
int lineByte=(m_imgWidth＊m_nBitCount/8+3)/4＊4;
//申請輸出圖像位圖數據緩沖區
m_pImgDataOut=new unsigned char[lineByte＊m_imgHeight];
//循環變量，圖像的坐標
int i,j;
//二值化
for(i=0;i<m_imgHeight;i++){
for(j=0;j<m_imgWidth;j++){
if(＊(m_pImgData+i＊lineByte+j)<threshold)
＊(m_pImgDataOut+i＊lineByte+j)=0;
else
＊(m_pImgDataOut+i＊lineByte+j)=255;
}
}
}
else
{
if(m_pImgDataOut!=NULL){
delete []m_pImgDataOut;
m_pImgDataOut=NULL;
}
if(m_lpColorTableOut!=NULL){
delete []m_lpColorTableOut;
m_lpColorTableOut=NULL;
}
//灰值化后，每像素位數為8比特
m_nBitCountOut=8;
//顏色表長度
m_nColorTableLengthOut=ComputeColorTabalLength(m_nBitCountOut);
//申請顏色表緩沖區，生成灰度圖像的顏色表
if(m_nColorTableLengthOut!=0){
m_lpColorTableOut=new RGBQUAD[m_nColorTableLengthOut];
for(int i=0; i<m_nColorTableLengthOut;i++){
m_lpColorTableOut[i].rgbBlue=i;
m_lpColorTableOut[i].rgbGreen=i;
m_lpColorTableOut[i].rgbRed=i;
m_lpColorTableOut[i].rgbReserved=0;
}
}
//輸入圖像每像素字節數，彩色圖像為3字節/像素
int pixelByteIn=3;
//輸入圖像每行像素所占字節數，必須是4的倍數
int lineByteIn=(m_imgWidth＊pixelByteIn+3)/4＊4;
//輸出圖像的寬高，與輸入圖像相等
m_imgWidthOut=m_imgWidth;
m_imgHeightOut=m_imgHeight;
//輸出圖像每行像素所占字節數，必須是4的倍數
int lineByteOut=(m_imgWidth＊m_nBitCountOut/8+3)/4＊4;
//申請輸出圖像位圖數據緩沖區
m_pImgDataOut=new unsigned char[lineByteOut＊m_imgHeight];
//循環變量，圖像的坐標
int m,n;
//根據灰值化公式為輸出圖像賦值
for(m=0;m<m_imgHeight;m++){
for(n=0;n<m_imgWidth;n++)
＊(m_pImgDataOut+m＊lineByteOut+n)=0.11＊＊(m_pImgData+m＊
lineByteIn+n＊pixelByteIn+0)
+0.59＊＊(m_pImgData+m＊lineByteIn+n＊pixelByteIn+1)
+0.30＊＊(m_pImgData+m＊lineByteIn+n＊pixelByteIn+2)+0.5;
}
//輸出圖像每行像素所占字節數，輸入圖像與輸出圖像每行像素所占字節數不等
int i,j;
//二值化
for(i=0;i<m_imgHeight;i++){
for(j=0;j<m_imgWidth;j++)
if(＊(m_pImgDataOut+i＊lineByteOut+j)<threshold)
＊(m_pImgDataOut+i＊lineByteOut+j)=0;
else
＊(m_pImgDataOut+i＊lineByteOut+j)=255;
}
}
}