Qt开发的程序一般都要借助qmake生成makefile文件。因此为了加入opencv库就要修改.pro文件，下面是Linux下该文件的配置。(增加的部分)
INCLUDEPATH += . /usr/local/include/opencv
LIBS += /usr/local/lib/libcv.so \
/usr/local/lib/libcvaux.so \
/usr/local/lib/libcxcore.so \
/usr/local/lib/libhighgui.so \
/usr/local/lib/libml.so
Opencv中通过摄像头捕捉到的每帧图像的数据结构是IplImage类型的，要把它显示到Qt窗口中就需要把它转化为QImage类型的图像。
#include <QVector>
#include <cstring>
QImage MyThread::IplImageToQImage(const IplImage * iplImage,double mini, double maxi)
...{
uchar *qImageBuffer = NULL;
int width = iplImage->width;
/**//* Note here that OpenCV image is stored so that each lined is
32-bits aligned thus
* explaining the necessity to "skip" the few last bytes of each
line of OpenCV image buffer.
*/
int widthStep = iplImage->widthStep;
int height = iplImage->height;
switch (iplImage->depth)
...{
case IPL_DEPTH_8U:
if(iplImage->nChannels == 1)
...{
/**//* OpenCV image is stored with one byte grey pixel. We convert it
to an 8 bit depth QImage.
*/
qImageBuffer = (uchar *) malloc(width*height*sizeof(uchar));
uchar *QImagePtr = qImageBuffer;
const uchar *iplImagePtr = (const uchar *) iplImage->imageData;
for(int y = 0; y < height; y++)
...{
// Copy line by line
memcpy(QImagePtr, iplImagePtr, width);
QImagePtr += width;
iplImagePtr += widthStep;
}
}
else if(iplImage->nChannels == 3)
...{
/**//* OpenCV image is stored with 3 byte color pixels (3 channels).
We convert it to a 32 bit depth QImage.
*/
qImageBuffer = (uchar *) malloc(width*height*4*sizeof(uchar));
uchar *QImagePtr = qImageBuffer;
const uchar *iplImagePtr = (const uchar *) iplImage->imageData;
for(int y = 0; y < height; y++)
...{
for (int x = 0; x < width; x++)
...{
// We cannot help but copy manually.
QImagePtr[0] = iplImagePtr[0];
QImagePtr[1] = iplImagePtr[1];
QImagePtr[2] = iplImagePtr[2];
QImagePtr[3] = 0;
QImagePtr += 4;
iplImagePtr += 3;
}
iplImagePtr += widthStep-3*width;
}
}
else
...{
qDebug("IplImageToQImage: image format is not supported : depth=8U and %d channels ", iplImage->nChannels);
}
break;
case IPL_DEPTH_16U:
if(iplImage->nChannels == 1)
...{
/**//* OpenCV image is stored with 2 bytes grey pixel. We convert it
to an 8 bit depth QImage.
*/
qImageBuffer = (uchar *) malloc(width*height*sizeof(uchar));
uchar *QImagePtr = qImageBuffer;
//const uint16_t *iplImagePtr = (const uint16_t *);
const unsigned int *iplImagePtr = (const unsigned int *)iplImage->imageData;
for (int y = 0; y < height; y++)
...{
for (int x = 0; x < width; x++)
...{
// We take only the highest part of the 16 bit value. It is
//similar to dividing by 256.
*QImagePtr++ = ((*iplImagePtr++) >> 8);
}
iplImagePtr += widthStep/sizeof(unsigned int)-width;
}
}
else
...{
qDebug("IplImageToQImage: image format is not supported : depth=16U and %d channels ", iplImage->nChannels);
}
break;
case IPL_DEPTH_32F:
if(iplImage->nChannels == 1)
...{
/**//* OpenCV image is stored with float (4 bytes) grey pixel. We
convert it to an 8 bit depth QImage.
*/
qImageBuffer = (uchar *) malloc(width*height*sizeof(uchar));
uchar *QImagePtr = qImageBuffer;
const float *iplImagePtr = (const float *) iplImage->imageData;
for(int y = 0; y < height; y++)
...{
for(int x = 0; x < width; x++)
...{
uchar p;
float pf = 255 * ((*iplImagePtr++) - mini) / (maxi - mini);
if(pf < 0) p = 0;
else if(pf > 255) p = 255;
else p = (uchar) pf;
*QImagePtr++ = p;
}
iplImagePtr += widthStep/sizeof(float)-width;
}
}
else
...{
qDebug("IplImageToQImage: image format is not supported : depth=32F and %d channels ", iplImage->nChannels);
}
break;
case IPL_DEPTH_64F:
if(iplImage->nChannels == 1)
...{
/**//* OpenCV image is stored with double (8 bytes) grey pixel. We
convert it to an 8 bit depth QImage.
*/
qImageBuffer = (uchar *) malloc(width*height*sizeof(uchar));
uchar *QImagePtr = qImageBuffer;
const double *iplImagePtr = (const double *) iplImage->imageData;
for(int y = 0; y < height; y++)
...{
for(int x = 0; x < width; x++)
...{
uchar p;
double pf = 255 * ((*iplImagePtr++) - mini) / (maxi - mini);
if(pf < 0) p = 0;
else if(pf > 255) p = 255;
else p = (uchar) pf;
*QImagePtr++ = p;
}
iplImagePtr += widthStep/sizeof(double)-width;
}
}
else
...{
qDebug("IplImageToQImage: image format is not supported : depth=64F and %d channels ", iplImage->nChannels);
}
break;
default:
qDebug("IplImageToQImage: image format is not supported : depth=%d and %d channels ", iplImage->depth, iplImage->nChannels);
}
QImage qImage;
QVector<QRgb> vcolorTable;
if(iplImage->nChannels == 1)
...{
// We should check who is going to destroy this allocation.
QRgb *colorTable = new QRgb[256];
for(int i = 0; i < 256; i++)
...{
colorTable[i] = qRgb(i, i, i);
vcolorTable[i] = colorTable[i];
}
qImage = QImage(qImageBuffer, width, height, QImage::Format_Indexed8).copy();
qImage.setColorTable(vcolorTable);
}
else
...{
qImage = QImage(qImageBuffer, width, height, QImage::Format_RGB32).copy();
}
free(qImageBuffer);
return qImage;
}
于是你可以下面的代码(部分)测试一下：摄像头获取每一帧IplImage*类型的图像，转化为QImage类型的图像，用update()发出一个paintEvent(QPaintEvent*)事件，如此不断更新图像。(IplImageToQImage中的mini和maxi默认初始化为0)
void ImageViewer::paintEvent(QPaintEvent *)...{
QPainter painter(this);
painter.drawImage(QPoint(0,0), *image);
}
bool ImageViewer::ShowImage()...{
IplImage *pImage = NULL;
CvCapture *pCapture = NULL;
if((pCapture = cvCaptureFromCAM(-1)) == NULL)...{
cout << "Open camera failed! ";
return false;
}
while((pImage = cvQueryFrame(pCapture)) != NULL)...{
image = IplImageToQImage(pImage);
update();
}
cvReleaseImage(&pImage);
cvReleaseCapture(&pCapture);
return true;
}
本文来自CSDN博客，转载请标明出处：http://blog.csdn.net/icesorrow/archive/2007/09/16/1787427.aspx