Problem to make a homography of detected document
i'm developping an app to detect document passed under a webcam.
I'm using Emgu.CV, an extension of opencv.
My detected document
I want to make an homogarphy of the detected document in a perfect rectangle.
I don't understand how to make it, can anyone help me ?
"largestContour" is the 4 sides contour detected by an approxPolyDp method.
Here's my code :
Rectangle rectangle = CvInvoke.BoundingRectangle(largestContour);
// Order coordinate (top-left - top-right - bottom-right - bottom-left)
var ptsList = largestContour.ToArray().ToList().OrderBy(a => a.Y).ThenBy(a => a.X).ToArray();
var elementAt1 = ptsList[1];
var elementAt3 = ptsList[3];
ptsList[1] = elementAt3;
ptsList[3] = elementAt1;
Point dstPoints = new
{
new Point(0, 0),
new Point(rectangle.Width, 0),
new Point(rectangle.Width, rectangle.Height),
new Point(0, rectangle.Height)
};
// Coordinates of the future image
Mat homographie = new Mat();
Mat final = new Mat();
CvInvoke.FindHomography(new VectorOfPoint(ptsList), new VectorOfPoint(dstPoints), homographie);
CvInvoke.WarpPerspective(largestContour, final, homographie, rectangle.Size);
CvInvoke.Imshow("Output", final);
opencv transform detection homography
asked Nov 23 '18 at 11:44
O. SaviozO. Savioz
12
add a comment |
i'm developping an app to detect document passed under a webcam.
I'm using Emgu.CV, an extension of opencv.
My detected document
I want to make an homogarphy of the detected document in a perfect rectangle.
I don't understand how to make it, can anyone help me ?
"largestContour" is the 4 sides contour detected by an approxPolyDp method.
Here's my code :
Rectangle rectangle = CvInvoke.BoundingRectangle(largestContour);
// Order coordinate (top-left - top-right - bottom-right - bottom-left)
var ptsList = largestContour.ToArray().ToList().OrderBy(a => a.Y).ThenBy(a => a.X).ToArray();
var elementAt1 = ptsList[1];
var elementAt3 = ptsList[3];
ptsList[1] = elementAt3;
ptsList[3] = elementAt1;
Point dstPoints = new
{
new Point(0, 0),
new Point(rectangle.Width, 0),
new Point(rectangle.Width, rectangle.Height),
new Point(0, rectangle.Height)
};
// Coordinates of the future image
Mat homographie = new Mat();
Mat final = new Mat();
CvInvoke.FindHomography(new VectorOfPoint(ptsList), new VectorOfPoint(dstPoints), homographie);
CvInvoke.WarpPerspective(largestContour, final, homographie, rectangle.Size);
CvInvoke.Imshow("Output", final);
opencv transform detection homography
asked Nov 23 '18 at 11:44
O. SaviozO. Savioz
12
add a comment |
i'm developping an app to detect document passed under a webcam.
I'm using Emgu.CV, an extension of opencv.
My detected document
I want to make an homogarphy of the detected document in a perfect rectangle.
I don't understand how to make it, can anyone help me ?
"largestContour" is the 4 sides contour detected by an approxPolyDp method.
Here's my code :
Rectangle rectangle = CvInvoke.BoundingRectangle(largestContour);
// Order coordinate (top-left - top-right - bottom-right - bottom-left)
var ptsList = largestContour.ToArray().ToList().OrderBy(a => a.Y).ThenBy(a => a.X).ToArray();
var elementAt1 = ptsList[1];
var elementAt3 = ptsList[3];
ptsList[1] = elementAt3;
ptsList[3] = elementAt1;
Point dstPoints = new
{
new Point(0, 0),
new Point(rectangle.Width, 0),
new Point(rectangle.Width, rectangle.Height),
new Point(0, rectangle.Height)
};
// Coordinates of the future image
Mat homographie = new Mat();
Mat final = new Mat();
CvInvoke.FindHomography(new VectorOfPoint(ptsList), new VectorOfPoint(dstPoints), homographie);
CvInvoke.WarpPerspective(largestContour, final, homographie, rectangle.Size);
CvInvoke.Imshow("Output", final);
opencv transform detection homography
asked Nov 23 '18 at 11:44
O. SaviozO. Savioz
12
i'm developping an app to detect document passed under a webcam.
I'm using Emgu.CV, an extension of opencv.
My detected document
I want to make an homogarphy of the detected document in a perfect rectangle.
I don't understand how to make it, can anyone help me ?
"largestContour" is the 4 sides contour detected by an approxPolyDp method.
Here's my code :
Rectangle rectangle = CvInvoke.BoundingRectangle(largestContour);
// Order coordinate (top-left - top-right - bottom-right - bottom-left)
var ptsList = largestContour.ToArray().ToList().OrderBy(a => a.Y).ThenBy(a => a.X).ToArray();
var elementAt1 = ptsList[1];
var elementAt3 = ptsList[3];
ptsList[1] = elementAt3;
ptsList[3] = elementAt1;
Point dstPoints = new
{
new Point(0, 0),
new Point(rectangle.Width, 0),
new Point(rectangle.Width, rectangle.Height),
new Point(0, rectangle.Height)
};
// Coordinates of the future image
Mat homographie = new Mat();
Mat final = new Mat();
CvInvoke.FindHomography(new VectorOfPoint(ptsList), new VectorOfPoint(dstPoints), homographie);
CvInvoke.WarpPerspective(largestContour, final, homographie, rectangle.Size);
CvInvoke.Imshow("Output", final);
opencv transform detection homography
opencv transform detection homography
asked Nov 23 '18 at 11:44
O. SaviozO. Savioz
12
asked Nov 23 '18 at 11:44
O. SaviozO. Savioz
12
asked Nov 23 '18 at 11:44
O. SaviozO. Savioz
12
asked Nov 23 '18 at 11:44
O. SaviozO. Savioz
12
asked Nov 23 '18 at 11:44
O. SaviozO. Savioz
12
12
add a comment |
add a comment |
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