如何将OpenCV::Mat转换为QImage 我想知道我如何将OpenCV C++标准CV::Mat类型转换为QImage。我一直在四处寻找,但运气不好。我发现了一些将IPlimage转换为QImage的代码,但这不是我想要的。谢谢。
cv::Mat有一个到IplImage的转换操作符,因此如果您有一些东西可以将IplImage转换为QImage,只需使用它(或者进行-可能是轻微的-调整以直接获取cv::Mat,内存布局是相同的,“只是”标题不同。)要将如何将OpenCV::Mat转换为QImage 我想知道我如何将OpenCV C++标准CV::Mat类型转换为QImage。我一直在四处寻找,但运气不好。我发现了一些将IPlimage转换为QImage的代码,但这不是我想要的。谢谢。,c++,qt,opencv,qimage,C++,Qt,Opencv,Qimage,cv::Mat有一个到IplImage的转换操作符,因此如果您有一些东西可以将IplImage转换为QImage,只需使用它(或者进行-可能是轻微的-调整以直接获取cv::Mat,内存布局是相同的,“只是”标题不同。)要将cv::Mat转换为QImage,您可以尝试使用QImage(uchar*数据、int-width、int-height、Format-Format)构造函数,如下所示(Mat是cv::Mat): 它比手动将像素转换为QImage更有效,但您必须将原始cv::Mat图像保留在内
cv::Mat
转换为QImage
,您可以尝试使用QImage(uchar*数据、int-width、int-height、Format-Format)
构造函数,如下所示(Mat
是cv::Mat
):
它比手动将像素转换为QImage
更有效,但您必须将原始cv::Mat
图像保留在内存中。它可以很容易地转换为QPixmap
,并使用QLabel
显示:
QPixmap pixmap = QPixmap::fromImage(img);
myLabel.setPixmap(pixmap);
更新
因为OpenCV默认使用BGR顺序,所以您应该首先使用cvtColor(src、dst、CV_BGR2RGB)
来获得Qt理解的图像布局
更新2:
如果您试图显示的图像具有非标准(当它是非连续的子矩阵时),则图像可能会出现扭曲。在这种情况下,最好使用cv::Mat::step1()
显式指定步幅:
演示如何将QImage
转换为OpenCV的IplImage
,反之亦然
之后,如果您需要帮助在IplImage*
到cv::Mat
之间转换:
// Assume data is stored by:
// IplImage* image;
cv::Mat mat(image, true); // Copies the data from image
cv::Mat mat(image, false); // Doesn't copy the data!
这是一个黑客程序,但可以完成任务。这里是24位RGB和灰度浮点的代码。可轻松调整其他类型。这是最有效的
QImage Mat2QImage(const cv::Mat3b &src) {
QImage dest(src.cols, src.rows, QImage::Format_ARGB32);
for (int y = 0; y < src.rows; ++y) {
const cv::Vec3b *srcrow = src[y];
QRgb *destrow = (QRgb*)dest.scanLine(y);
for (int x = 0; x < src.cols; ++x) {
destrow[x] = qRgba(srcrow[x][2], srcrow[x][1], srcrow[x][0], 255);
}
}
return dest;
}
QImage Mat2QImage(const cv::Mat_<double> &src)
{
double scale = 255.0;
QImage dest(src.cols, src.rows, QImage::Format_ARGB32);
for (int y = 0; y < src.rows; ++y) {
const double *srcrow = src[y];
QRgb *destrow = (QRgb*)dest.scanLine(y);
for (int x = 0; x < src.cols; ++x) {
unsigned int color = srcrow[x] * scale;
destrow[x] = qRgba(color, color, color, 255);
}
}
return dest;
}
QImage Mat2QImage(常量cv::Mat3b和src){
QImage dest(src.cols、src.rows、QImage::Format_ARGB32);
对于(int y=0;y
这就是我的工作。我修改了上面Michal Kottman的代码。Michal Kottman的答案是有效的,并给出了一些图像的预期结果,但在某些情况下会失败。这是我找到的解决这个问题的办法
QImage imgIn= QImage((uchar*) img.data, img.cols, img.rows, img.step, QImage::Format_RGB888);
不同之处在于增加了img.step部分。qt没有它不会抱怨,但是一些图像没有它就不能正常显示。希望这会有所帮助。对深度图像使用静态函数convert16uc1:
QPixmap Viewer::convert16uc1(const cv::Mat& source)
{
quint16* pSource = (quint16*) source.data;
int pixelCounts = source.cols * source.rows;
QImage dest(source.cols, source.rows, QImage::Format_RGB32);
char* pDest = (char*) dest.bits();
for (int i = 0; i < pixelCounts; i++)
{
quint8 value = (quint8) ((*(pSource)) >> 8);
*(pDest++) = value; // B
*(pDest++) = value; // G
*(pDest++) = value; // R
*(pDest++) = 0; // Alpha
pSource++;
}
return QPixmap::fromImage(dest);
}
QPixmap Viewer::convert8uc3(const cv::Mat& source)
{
quint8* pSource = source.data;
int pixelCounts = source.cols * source.rows;
QImage dest(source.cols, source.rows, QImage::Format_RGB32);
char* pDest = (char*) dest.bits();
for (int i = 0; i < pixelCounts; i++)
{
*(pDest++) = *(pSource+2); // B
*(pDest++) = *(pSource+1); // G
*(pDest++) = *(pSource+0); // R
*(pDest++) = 0; // Alpha
pSource+=3;
}
return QPixmap::fromImage(dest);
}
QPixmap Viewer::convert16uc3(const cv::Mat& source)
{
quint16* pSource = (quint16*) source.data;
int pixelCounts = source.cols * source.rows;
QImage dest(source.cols, source.rows, QImage::Format_RGB32);
char* pDest = (char*) dest.bits();
for (int i = 0; i < pixelCounts; i++)
{
*(pDest++) = *(pSource+2); // B
*(pDest++) = *(pSource+1); // G
*(pDest++) = *(pSource+0); // R
*(pDest++) = 0; // Alpha
pSource+=3;
}
return QPixmap::fromImage(dest);
}
QPixmap查看器::convert16uc1(const-cv::Mat&source)
{
quint16*pSource=(quint16*)source.data;
int pixelCounts=source.cols*source.rows;
QImage dest(source.cols、source.rows、QImage::Format_RGB32);
char*pDest=(char*)dest.bits();
对于(int i=0;i>8);
*(pDest++)=值;//B
*(pDest++)=值;//G
*(pDest++)=值;//R
*(pDest++)=0;//α
pSource++;
}
返回QPixmap::fromImage(dest);
}
QPixmap查看器::convert8uc3(常量cv::Mat和源)
{
quint8*pSource=source.data;
int pixelCounts=source.cols*source.rows;
QImage dest(source.cols、source.rows、QImage::Format_RGB32);
char*pDest=(char*)dest.bits();
对于(int i=0;i
这对我很有帮助。它有点狡猾,性能很差(如评论中所指出的),但是可以使用到目前为止我所使用的所有颜色格式,而且操作非常简单
程序如下:
cv::Mat image = //...some image you want to display
// 1. Save the cv::Mat to some temporary file
cv::imwrite("../Images/tmp.jpg",image);
// 2. Load the image you just saved as a QImage
QImage img;
img.load("../Images/tmp.jpg");
完成强>
例如,如果要在QLabel中显示它,请继续执行以下操作:
// Set QImage as content of MyImageQLabel
ui-> MyImageQLabel->setPixmap(QPixmap::fromImage(img, Qt::AutoColor));
我个人将其用于一个简单的图像编辑器。我也有与您相同的问题,因此我开发了四个函数来减轻我的痛苦,它们是
QImage mat_to_qimage_cpy(cv::Mat const &mat, bool swap = true);
QImage mat_to_qimage_ref(cv::Mat &mat, bool swap = true);
cv::Mat qimage_to_mat_cpy(QImage const &img, bool swap = true);
cv::Mat qimage_to_mat_ref(QImage &img, bool swap = true);
这些函数可以处理1、3、4个通道的图像,每个像素必须只占用一个字节(CV_8U->Format_Indexed8,CV_8UC3->QImage::Format_RGB888,CV_8UC4->QImage::Format_ARGB32),我还没有处理其他类型(QImage::Format_RGB16,QImage::Format_RGB666等等)。代码位于
在
**将mat转换为Qimage**的关键概念是
/**
* @brief copy QImage into cv::Mat
*/
struct mat_to_qimage_cpy_policy
{
static QImage start(cv::Mat const &mat, QImage::Format format)
{
//The fourth parameters--mat.step is crucial, because
//opencv may do padding on every row, you need to tell
//the qimage how many bytes per row
//The last thing is if you want to copy the buffer of cv::Mat
//to the qimage, you need to call copy(), else the qimage
//will share the buffer of cv::Mat
return QImage(mat.data, mat.cols, mat.rows, mat.step, format).copy();
}
};
struct mat_to_qimage_ref_policy
{
static QImage start(cv::Mat &mat, QImage::Format format)
{
//every thing are same as copy policy, but this one share
//the buffer of cv::Mat but not copy
return QImage(mat.data, mat.cols, mat.rows, mat.step, format);
}
};
将cv::Mat转换为Qimage的关键概念是
/**
* @brief copy QImage into cv::Mat
*/
struct qimage_to_mat_cpy_policy
{
static cv::Mat start(QImage const &img, int format)
{
//same as convert mat to qimage, the fifth parameter bytesPerLine()
//indicate how many bytes per row
//If you want to copy the data you need to call clone(), else QImage
//cv::Mat will share the buffer
return cv::Mat(img.height(), img.width(), format,
const_cast<uchar*>(img.bits()), img.bytesPerLine()).clone();
}
};
/**
* @brief make Qimage and cv::Mat share the same buffer, the resource
* of the cv::Mat must not deleted before the QImage finish
* the jobs.
*/
struct qimage_to_mat_ref_policy
{
static cv::Mat start(QImage &img, int format)
{
//same as copy policy, but this one will share the buffer
return cv::Mat(img.height(), img.width(), format,
img.bits(), img.bytesPerLine());
}
};
/**
*@short将QImage复制到cv::Mat
*/
结构qimage_到材料cpy_策略
{
静态cv::Mat start(QImage const&img,int格式)
QImage mat_to_qimage_cpy(cv::Mat const &mat, bool swap = true);
QImage mat_to_qimage_ref(cv::Mat &mat, bool swap = true);
cv::Mat qimage_to_mat_cpy(QImage const &img, bool swap = true);
cv::Mat qimage_to_mat_ref(QImage &img, bool swap = true);
/**
* @brief copy QImage into cv::Mat
*/
struct mat_to_qimage_cpy_policy
{
static QImage start(cv::Mat const &mat, QImage::Format format)
{
//The fourth parameters--mat.step is crucial, because
//opencv may do padding on every row, you need to tell
//the qimage how many bytes per row
//The last thing is if you want to copy the buffer of cv::Mat
//to the qimage, you need to call copy(), else the qimage
//will share the buffer of cv::Mat
return QImage(mat.data, mat.cols, mat.rows, mat.step, format).copy();
}
};
struct mat_to_qimage_ref_policy
{
static QImage start(cv::Mat &mat, QImage::Format format)
{
//every thing are same as copy policy, but this one share
//the buffer of cv::Mat but not copy
return QImage(mat.data, mat.cols, mat.rows, mat.step, format);
}
};
/**
* @brief copy QImage into cv::Mat
*/
struct qimage_to_mat_cpy_policy
{
static cv::Mat start(QImage const &img, int format)
{
//same as convert mat to qimage, the fifth parameter bytesPerLine()
//indicate how many bytes per row
//If you want to copy the data you need to call clone(), else QImage
//cv::Mat will share the buffer
return cv::Mat(img.height(), img.width(), format,
const_cast<uchar*>(img.bits()), img.bytesPerLine()).clone();
}
};
/**
* @brief make Qimage and cv::Mat share the same buffer, the resource
* of the cv::Mat must not deleted before the QImage finish
* the jobs.
*/
struct qimage_to_mat_ref_policy
{
static cv::Mat start(QImage &img, int format)
{
//same as copy policy, but this one will share the buffer
return cv::Mat(img.height(), img.width(), format,
img.bits(), img.bytesPerLine());
}
};
Mat mat = imread("path/to/image.jpg");
cvtColor(mat, mat, CV_BGR2RGB);
QImage image(mat.data, mat.cols, mat.rows, QImage::Format_RGB888);
QImage image = QImage(mat.data, mat.cols, mat.rows, QImage::Format_RGB888).rgbSwapped());