Android Question OpenCV fillpoly method java.utils.list


Active Member
Licensed User
Hi, i try to fill a contour with a list of points with some code like this:
   Dim contours as List
    contours.Initialize 'reset and find the contours again
    mImgProc.findContours(ContourMat, contours, hierarchy, mImgProc.RETR_External,mImgProc.CHAIN_APPROX_SIMPLE, offset)
    For i=0 To contours.Size-1
        Dim mat As OCVMatOfPoint = contours.Get(i)
        a = mImgProc.contourArea(contours.Get(i),False) 'true means closed shape, which is not always the case
        If a>5 Then 'there must be an aera of some size, otherwise it is just a line
            Dim pnt() As OCVPoint = mat.toArray
            Dim pntlist As List
            mImgProc.fillPoly1(ContourMat,[B]pntlist[/B] ,grayscalarwhite)
            Log("i: "&i&", area: " & a &" number of points: "&pnt.Length )    'the area is only the white pixels, not the encompassing area
        End If
However I have not found out how the second parameter of the call mImgProc.fillPoly1, the "pts of java.utils.list" must be set up. Whatever I write there throw a run tim eexception that parameters cannot be cast to whatever. The find contours method works okay.
Thanks for help


Licensed User
mat.toList instead of pntlist does not work?
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Active Member
Licensed User
You mean like this?
            Dim pntlist As List = mat.tolist
            mImgProc.fillPoly1(ContourMat,pntlist ,grayscalarwhite)
That throws an exception:
java.lang.ClassCastException: org.opencv.core.Point cannot be cast to org.opencv.core.MatOfPoint
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