I'm trying to convert Image RAW10 to cv::Mat. But in the finish, I have always gray square. The conversation I make like:
void ConvertToMat(unsigned char * buffer, unsigned int width, unsigned int height) {
cv::Mat img;
cv::Mat raw(height, width, CV_8UC1, buffer);
raw.convertTo(img, CV_32FC1, 255.0); // -> don't work
cv::imwrite("myimage.png", img);
cv::cvtColor(raw, raw, cv::COLOR_BayerGR2RGBA); //-> also don't work
cv::imwrite("myimage.png", raw);
}
Related
I am using a Scalar to define the color of a rectangle I am drawing with OpenCV:
rectangle(imgOriginal, Point(0, 0), Point(25, 50), Scalar(H, S, V), CV_FILLED);
However, the color is defined in HSV color space rather than RGB (imgOriginal is RGB).
How do I convert Scalar (or its input, the integer variables H, S, and V) to RGB?
(So far I only found answers telling me how to convert a whole image with cvtColor which is not what I want.)
Although not optimal, You can use the following:
Scalar ScalarHSV2BGR(uchar H, uchar S, uchar V) {
Mat rgb;
Mat hsv(1,1, CV_8UC3, Scalar(H,S,V));
cvtColor(hsv, rgb, CV_HSV2BGR);
return Scalar(rgb.data[0], rgb.data[1], rgb.data[2]);
}
This worked for me,
Mat rgb;
Mat hsv(1, 1, CV_8UC3, Scalar(224, 224, 160));
cvtColor(hsv, rgb, CV_HSV2BGR);
Scalar rgb = Scalar((int)rgb.at<cv::Vec3b>(0, 0)[0],(int)rgb.at<cv::Vec3b>(0, 0)[0],(int)rgb.at<cv::Vec3b>(0, 0)[0])
OpenCV 3.2.0. Note: h is in range [0,360] and l and s is in [0,1]
Mat hls(1, 1, CV_32FC3, Scalar(h, l, s));
Mat rgb;
cvtColor(hls, rgb, COLOR_HLS2RGB);
Scalar c = Scalar(255*rgb.at<float>(0,0), 255*rgb.at<float>(0,1), 255*rgb.at<float>(0,2));
Use this to convert a single value:
cv::Vec3f rgb;
cv::Vec3f hsv;
hsv[0] = H;
hsv[1] = S;
hsv[2] = V;
cvtColor(hsv, rgb, CV_HSV2BGR);
Then you can use it:
rectangle(imgOriginal, Point(0, 0), Point(25, 50),
Scalar(rgb[0], rgb[1], rgb[2]), CV_FILLED);
i want to convert an image from cvMat type to Qimage , with my actual code the application does not work; i have did it the other way (Qimage to Mat it work fine)
please tell me what is going on wrong with my code
here is my code for Qimage to Mat :
Mat qimage2mat(const QImage& qimage) {
cv::Mat mat = cv::Mat(qimage.height(), qimage.width(), CV_8UC4, (uchar*)qimage.bits(), qimage.bytesPerLine());
cv::Mat mat2 = cv::Mat(mat.rows, mat.cols, CV_8UC3 );
int from_to[] = { 0,0, 1,1, 2,2 };
cv::mixChannels( &mat, 1, &mat2, 1, from_to, 3 );
return mat2;
}
and here is my code for Mat to Qimage
QImage mat2qimage(const Mat& mat) {
Mat rgb;
cvtColor(mat, rgb, CV_BGR2RGB);
return QImage((const unsigned char*)(rgb.data), rgb.cols, rgb.rows, QImage::Format_RGB888);
}
thank you by advance
as #SpamBot mentioned, the data is freed when Mat goes out of scope. try deep copying the data:
QImage mat2qimage(const Mat& mat)
{
Mat rgb;
cvtColor(mat, rgb, CV_BGR2RGB);
return QImage((const unsigned char*)(rgb.data), rgb.cols, rgb.rows, QImage::Format_RGB888).copy();
}
I want to convert an image from Mat type in OpenCV that has floating-point values into a QImage.
I did it the other way (from QImage to Mat), and here is my code :
Mat qimage2mat(const QImage& qimage) {
cv::Mat mat = cv::Mat(qimage.height(), qimage.width(), CV_8UC4, (uchar*)qimage.bits(), qimage.bytesPerLine());
cv::Mat mat2 = cv::Mat(mat.rows, mat.cols, CV_8UC3 );
int from_to[] = { 0,0, 1,1, 2,2 };
cv::mixChannels( &mat, 1, &mat2, 1, from_to, 3 );
return mat2;
}
How can I do it from Mat to QImage ?
When I convert a QImage to cv::Mat the Mat comes out blurred.
This is the code that converts it:
QPixmap pixmap(*ui->imgLabel->pixmap());
QImage image = pixmap.toImage();
image.convertToFormat(QImage::Format_RGB888);
Mat matImage = Mat(image.height(), image.width(), CV_8UC3, image.scanLine(0));
This is the original image zoomed:
This is the image created:
Grateful for any help.
I don't know QT, but have you tried ready solutions from WEB? For example, from this link I found another method of conversion:
Mat qimage2mat(const QImage& qimage) {
cv::Mat mat = cv::Mat(qimage.height(), qimage.width(), CV_8UC4, (uchar*)qimage.bits(), qimage.bytesPerLine());
cv::Mat mat2 = cv::Mat(mat.rows, mat.cols, CV_8UC3 );
int from_to[] = { 0,0, 1,1, 2,2 };
cv::mixChannels( &mat, 1, &mat2, 1, from_to, 3 );
return mat2;
};
I hope you could help me.
I' m using QT and try to do a simple detection of edges on a image. But my program crash when i launch
cv::GaussianBlur( src, src, cv::Size(3,3), 0, 0, cv::BORDER_DEFAULT );
or
cv::Sobel( src_gray, grad_x, ddepth, 1, 0, 3, scale, delta, cv::BORDER_DEFAULT );
here is my code:
QImage *image1;
IplImage *cv_image1;
image1 = new QImage("./image.png"); // Format is ARGB32
cv_image1 = QImage2IplImage(image1);
cv::Mat src(cv_image1);
cv::imshow(window_name, src); // Work Well
cv::Mat src_gray;
int scale = 1;
int delta = 0;
int ddepth = CV_16S;
cv::GaussianBlur(src, src, cv::Size(3,3), 0, 0, cv::BORDER_DEFAULT); //Crash Here
cv::imshow( window_name, src);
I think that was a problem of format.
But in another program with QIMAGES in ARGB32 this code work well.
Thank you.
Try going with proper QImage to cv::Mat conversion using this functions and you should be fine (I also included a conversion from cv::Mat to QImage):
cv::Mat cvmat_from_qimage(const QImage& qimage)
{
cv::Mat mat = cv::Mat(qimage.height(), qimage.width(), CV_8UC4, (uchar*)qimage.bits(), qimage.bytesPerLine());
cv::Mat mat2 = cv::Mat(mat.rows, mat.cols, CV_8UC3 );
int from_to[] = { 0,0, 1,1, 2,2 };
cv::mixChannels( &mat, 1, &mat2, 1, from_to, 3 );
return mat2;
}
QImage qimage_from_cvmat(const cv::Mat& mat)
{
cv::Mat rgb;
cvtColor(mat, rgb, CV_BGR2RGB);
return QImage((const unsigned char*)(rgb.data), rgb.cols, rgb.rows, QImage::Format_RGB888);
}
I Found a solution.
That' s weird but when I do:
cvtColor(src, src_gray, CV_RGB2GRAY );
cv::Sobel(src_gray, grad_x, ddepth, 1, 0, 3, scale, delta, cv::BORDER_CONSTANT);
without the cv::GaussianBlur it works well. I just change the last parameter to cv::BORDER_CONSTANT