Mixing
cv::Mat GRAY to RGBA and convert to UIImage
0
I have a 1 channel cv::Mat that I need to convert RGBA, whenever I do so the Image prints white(on IOS simulator).
UIImage *matToUIImage(cv::Mat grayMat){
std::cout << grayMat.channels() << std::endl;
//prints 1
cv::Mat alphaMat;
cv::cvtColor(grayMat, alphaMat, CV_GRAY2BGRA);
std::cout << alphaMat.channels() << std::endl;
//prints 4
alphaMat.convertTo(alphaMat, CV_8U);
UIImage *finalImage = MatToUIImage(alphaMat);
return finalImage;
}
when I run the same image without converting to alpha the image prints fine.
UIImage *matToUIImage(cv::Mat grayMat){
std::cout << grayMat.channels() << std::endl;
//prints 1
alphaMat.convertTo(alphaMat, CV_8U);
UIImage *finalImage = MatToUIImage(alphaMat);
return finalImage;
}
Also when I try to edit convertTo method
// alphaExist = 1
alphaMat.convertTo(alphaMat, CV_8U, 1);
I get the same white image.
How I print Image in swift:
@IBOutlet weak var photoImageView: UIImageView!
@IBAction func convertImage(_ sender: UIButton) {
photoImageView.image = OpenCVWrapper.convert(photoImageView.image)
}
c++ swift opencv
asked Nov 18 '18 at 21:26
Cristian Cristian
85115
add a comment |
0
I have a 1 channel cv::Mat that I need to convert RGBA, whenever I do so the Image prints white(on IOS simulator).
UIImage *matToUIImage(cv::Mat grayMat){
std::cout << grayMat.channels() << std::endl;
//prints 1
cv::Mat alphaMat;
cv::cvtColor(grayMat, alphaMat, CV_GRAY2BGRA);
std::cout << alphaMat.channels() << std::endl;
//prints 4
alphaMat.convertTo(alphaMat, CV_8U);
UIImage *finalImage = MatToUIImage(alphaMat);
return finalImage;
}
when I run the same image without converting to alpha the image prints fine.
UIImage *matToUIImage(cv::Mat grayMat){
std::cout << grayMat.channels() << std::endl;
//prints 1
alphaMat.convertTo(alphaMat, CV_8U);
UIImage *finalImage = MatToUIImage(alphaMat);
return finalImage;
}
Also when I try to edit convertTo method
// alphaExist = 1
alphaMat.convertTo(alphaMat, CV_8U, 1);
I get the same white image.
How I print Image in swift:
@IBOutlet weak var photoImageView: UIImageView!
@IBAction func convertImage(_ sender: UIButton) {
photoImageView.image = OpenCVWrapper.convert(photoImageView.image)
}
c++ swift opencv
asked Nov 18 '18 at 21:26
Cristian Cristian
85115
add a comment |
0
0
0
I have a 1 channel cv::Mat that I need to convert RGBA, whenever I do so the Image prints white(on IOS simulator).
UIImage *matToUIImage(cv::Mat grayMat){
std::cout << grayMat.channels() << std::endl;
//prints 1
cv::Mat alphaMat;
cv::cvtColor(grayMat, alphaMat, CV_GRAY2BGRA);
std::cout << alphaMat.channels() << std::endl;
//prints 4
alphaMat.convertTo(alphaMat, CV_8U);
UIImage *finalImage = MatToUIImage(alphaMat);
return finalImage;
}
when I run the same image without converting to alpha the image prints fine.
UIImage *matToUIImage(cv::Mat grayMat){
std::cout << grayMat.channels() << std::endl;
//prints 1
alphaMat.convertTo(alphaMat, CV_8U);
UIImage *finalImage = MatToUIImage(alphaMat);
return finalImage;
}
Also when I try to edit convertTo method
// alphaExist = 1
alphaMat.convertTo(alphaMat, CV_8U, 1);
I get the same white image.
How I print Image in swift:
@IBOutlet weak var photoImageView: UIImageView!
@IBAction func convertImage(_ sender: UIButton) {
photoImageView.image = OpenCVWrapper.convert(photoImageView.image)
}
c++ swift opencv
asked Nov 18 '18 at 21:26
Cristian Cristian
85115
I have a 1 channel cv::Mat that I need to convert RGBA, whenever I do so the Image prints white(on IOS simulator).
UIImage *matToUIImage(cv::Mat grayMat){
std::cout << grayMat.channels() << std::endl;
//prints 1
cv::Mat alphaMat;
cv::cvtColor(grayMat, alphaMat, CV_GRAY2BGRA);
std::cout << alphaMat.channels() << std::endl;
//prints 4
alphaMat.convertTo(alphaMat, CV_8U);
UIImage *finalImage = MatToUIImage(alphaMat);
return finalImage;
}
when I run the same image without converting to alpha the image prints fine.
UIImage *matToUIImage(cv::Mat grayMat){
std::cout << grayMat.channels() << std::endl;
//prints 1
alphaMat.convertTo(alphaMat, CV_8U);
UIImage *finalImage = MatToUIImage(alphaMat);
return finalImage;
}
Also when I try to edit convertTo method
// alphaExist = 1
alphaMat.convertTo(alphaMat, CV_8U, 1);
I get the same white image.
How I print Image in swift:
@IBOutlet weak var photoImageView: UIImageView!
@IBAction func convertImage(_ sender: UIButton) {
photoImageView.image = OpenCVWrapper.convert(photoImageView.image)
}
c++ swift opencv
c++ swift opencv
asked Nov 18 '18 at 21:26
Cristian Cristian
85115
asked Nov 18 '18 at 21:26
Cristian Cristian
85115
asked Nov 18 '18 at 21:26
Cristian Cristian
85115
asked Nov 18 '18 at 21:26
Cristian Cristian
85115
asked Nov 18 '18 at 21:26
Cristian Cristian
85115
85115
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
0
All I had to do was convert the Mat to CV_8U before I converted it to RGBA.
UIImage *matToUIImage(cv::Mat grayMat){
std::cout << grayMat.channels() << std::endl;
//prints 1
grayMat.convertTo(grayMat, CV_8U);
cv::Mat alphaMat;
cv::cvtColor(grayMat, alphaMat, CV_GRAY2BGRA);
std::cout << alphaMat.channels() << std::endl;
//prints 4
alphaMat.convertTo(alphaMat, CV_8U);
UIImage *finalImage = MatToUIImage(alphaMat);
return finalImage;
}
answered Nov 19 '18 at 19:33
Cristian Cristian
85115
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
0
All I had to do was convert the Mat to CV_8U before I converted it to RGBA.
UIImage *matToUIImage(cv::Mat grayMat){
std::cout << grayMat.channels() << std::endl;
//prints 1
grayMat.convertTo(grayMat, CV_8U);
cv::Mat alphaMat;
cv::cvtColor(grayMat, alphaMat, CV_GRAY2BGRA);
std::cout << alphaMat.channels() << std::endl;
//prints 4
alphaMat.convertTo(alphaMat, CV_8U);
UIImage *finalImage = MatToUIImage(alphaMat);
return finalImage;
}
answered Nov 19 '18 at 19:33
Cristian Cristian
85115
add a comment |
0
All I had to do was convert the Mat to CV_8U before I converted it to RGBA.
UIImage *matToUIImage(cv::Mat grayMat){
std::cout << grayMat.channels() << std::endl;
//prints 1
grayMat.convertTo(grayMat, CV_8U);
cv::Mat alphaMat;
cv::cvtColor(grayMat, alphaMat, CV_GRAY2BGRA);
std::cout << alphaMat.channels() << std::endl;
//prints 4
alphaMat.convertTo(alphaMat, CV_8U);
UIImage *finalImage = MatToUIImage(alphaMat);
return finalImage;
}
answered Nov 19 '18 at 19:33
Cristian Cristian
85115
add a comment |
0
0
0
All I had to do was convert the Mat to CV_8U before I converted it to RGBA.
UIImage *matToUIImage(cv::Mat grayMat){
std::cout << grayMat.channels() << std::endl;
//prints 1
grayMat.convertTo(grayMat, CV_8U);
cv::Mat alphaMat;
cv::cvtColor(grayMat, alphaMat, CV_GRAY2BGRA);
std::cout << alphaMat.channels() << std::endl;
//prints 4
alphaMat.convertTo(alphaMat, CV_8U);
UIImage *finalImage = MatToUIImage(alphaMat);
return finalImage;
}
answered Nov 19 '18 at 19:33
Cristian Cristian
85115
All I had to do was convert the Mat to CV_8U before I converted it to RGBA.
UIImage *matToUIImage(cv::Mat grayMat){
std::cout << grayMat.channels() << std::endl;
//prints 1
grayMat.convertTo(grayMat, CV_8U);
cv::Mat alphaMat;
cv::cvtColor(grayMat, alphaMat, CV_GRAY2BGRA);
std::cout << alphaMat.channels() << std::endl;
//prints 4
alphaMat.convertTo(alphaMat, CV_8U);
UIImage *finalImage = MatToUIImage(alphaMat);
return finalImage;
}
answered Nov 19 '18 at 19:33
Cristian Cristian
85115
answered Nov 19 '18 at 19:33
Cristian Cristian
85115
answered Nov 19 '18 at 19:33
Cristian Cristian
85115
answered Nov 19 '18 at 19:33
Cristian Cristian
85115
85115
add a comment |
add a comment |
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