裁剪位图文件--根据给的目标中心坐标从源图像中裁剪一块区域大小固定的图像，病存储

[wk119911]

BOOL CHVDlgSaveDlg::SaveBMPFile(LPCSTR lpFileName, BITMAPINFO *pBmpInfo, BYTE *pImageBuffer)
{
int nLineBytes=1628*3;
BOOL bRVal = TRUE;
DWORD dwBytesRead = 0;
DWORD dwSize = 0;
BITMAPFILEHEADER bfh = {0};
int nTable = 0;
DWORD dwImageSize = 0;

if (pBmpInfo->bmiHeader.biBitCount > 8)
{
nTable = 0;
}
else
{
nTable = 256;
}

dwImageSize = WIDTH_BYTES(460 * pBmpInfo->bmiHeader.biBitCount) * 360;


if (dwImageSize <= 0)
{
bRVal = FALSE;
}
else{
bfh.bfType = (WORD)'M' << 8 | 'B';
bfh.bfOffBits = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER) + nTable * sizeof(RGBQUAD);
bfh.bfSize = bfh.bfOffBits + dwImageSize;

for (int y=0; y<1628;y++)
{
for (int x=0;x<1236;x++)
{

if((x>=nx-230&&x<=nx+230)&&(y>=ny-180&&y<=ny+180))
{


*frameforcut=*(pImageBuffer+ bfh.bfOffBits+ nLineBytes*y+x*3);
frameforcut++;

*frameforcut=*(pImageBuffer+ bfh.bfOffBits+ nLineBytes*y+x*3+1);
frameforcut++;

*frameforcut=*(pImageBuffer+ bfh.bfOffBits +nLineBytes*y+x*3+2);
frameforcut++;
}
}
}

if(nx>230&&nx<1628-230)
{
frameforcut = frameforcut-460*3*360;//指针移到图像开始的地方

}

HANDLE hFile = ::CreateFile(lpFileName,
GENERIC_WRITE ,
0,
NULL,
CREATE_ALWAYS,
FILE_ATTRIBUTE_NORMAL,
NULL
);

if (hFile == INVALID_HANDLE_VALUE)
{
bRVal = FALSE;
}
else{
dwSize = sizeof(BITMAPFILEHEADER);
::WriteFile(hFile, &bfh, dwSize, &dwBytesRead, NULL );

dwSize = sizeof(BITMAPINFOHEADER) + nTable * sizeof(RGBQUAD);
::WriteFile(hFile, pBmpInfo, dwSize, &dwBytesRead, NULL );

dwSize = dwImageSize;
WriteFile(hFile, frameforcut, dwSize, &dwBytesRead, NULL );

CloseHandle(hFile);
}
}

return bRVal;
}

[wk119911]

补充：指针frameforcut 常在运行中跑飞

[wk119911]

补充一下：源图像大小为1628*1236 ，目标图像为460*360，目标中心是通过全局变量nx ,ny传进来的，大家帮忙看一下，这个程序写出的位图文件没有图像信息。

谢谢大家，不胜感激！

[向立天]

我觉得你可以这样
你可以在内存中把要裁剪下来的东西复制到一个dc中
然后将这个dc中的数据保存下来

[一名程序员]

[Quote=引用 7 楼 xianglitian 的回复:]
我觉得你可以这样
你可以在内存中把要裁剪下来的东西复制到一个dc中
然后将这个dc中的数据保存下来
[/Quote]这是一种简便的方法，在dc复制中指定复制区域大小和左上角坐标。

[wk119911]

谢谢楼上两位

[wk119911]

怎么没有回复啊

[向立天]

你的代码如果不进行裁剪是好用的么

[wk119911]

好用啊，谢谢

[wk119911]

修改后的代码：BOOL CHVDlgSaveDlg::SaveBMPFile(LPCSTR lpFileName, BYTE *pImageBuffer)
{

int nLineBytes=1628*3;
BOOL bRVal = TRUE;
DWORD dwBytesRead = 0;
DWORD dwSize = 0;
BITMAPFILEHEADER bfh = {0};
int nTable = 0;
DWORD dwImageSize = 0;

if((nx>=230&&nx<1628-230)&&(ny>=180&&ny<1236-180))
{


for (int y=0; y<1236;y++)
{
for (int x=0;x<1628*3;x++)
{

if( ((x>=nx-230)&&(x<nx+230))&&((y>=ny-180)&&(y<ny+180)))
{

*frameforcut=*(pImageBuffer+ nLineBytes*y+x*3);
frameforcut++;

*frameforcut=*(pImageBuffer+ nLineBytes*y+x*3+1);
frameforcut++;

*frameforcut=*(pImageBuffer+nLineBytes*y+x*3+2);
frameforcut++;

}
}
}


frameforcut = frameforcut-460*3*360 ; //指针移到图像开始的地方

}

dwImageSize = WIDTH_BYTES(460 * 24) * 360;
if (dwImageSize <= 0)
{
bRVal = FALSE;
}
else
{
bfh.bfType = (WORD)'M' << 8 | 'B';
bfh.bfOffBits = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER) + nTable * sizeof(RGBQUAD);
bfh.bfSize = bfh.bfOffBits + dwImageSize;
bfh.bfReserved1 = 0 ;
bfh.bfReserved2 = 0 ;
}

//******************************************************
BITMAPINFOHEADER pBmpInfo;
pBmpInfo.biBitCount = 24;/* 每个像素的位数，如256色，8bit */
pBmpInfo.biClrImportant = 0 ;
pBmpInfo.biClrUsed = 0 ;
pBmpInfo.biCompression = BI_RGB;
pBmpInfo.biPlanes = 1 ;
pBmpInfo.biSizeImage = 360*460*3;
pBmpInfo.biXPelsPerMeter = 0;
pBmpInfo.biYPelsPerMeter = 0;
pBmpInfo.biHeight = 360 ;
pBmpInfo.biWidth = 460 ;
pBmpInfo.biSize = 40 ;

//***********************************************************

HANDLE hFile = ::CreateFile(lpFileName,
GENERIC_WRITE ,
0,
NULL,
CREATE_ALWAYS,
FILE_ATTRIBUTE_NORMAL,
NULL
);

if (hFile == INVALID_HANDLE_VALUE)
{
bRVal = FALSE;
}
else
{
dwSize = sizeof(BITMAPFILEHEADER);
::WriteFile(hFile, &bfh, dwSize, &dwBytesRead, NULL );

dwSize = sizeof(BITMAPINFOHEADER) + nTable * sizeof(RGBQUAD);
::WriteFile(hFile, &pBmpInfo, dwSize, &dwBytesRead, NULL );

dwSize = dwImageSize;

WriteFile( hFile, frameforcut, dwSize, &dwBytesRead, NULL );


CloseHandle(hFile);

}
delete [] pImageBuffer ;
// delete [] frameforcut ;
return bRVal ;
}

问题还是没有解决