public unsafe static void where < T > (Mat src, Mat dst, Func <T, bool> condition, Mat x, Mat y) where
T : unmanaged
{
if (!src.IsContinuous() || !dst.IsContinuous() || !x.IsContinuous() || !y.IsContinuous())
{
throw new ArgumentException("all the Mat should be IsContinuous()==true");
}
//https://github.com/opencv/opencv/pull/8311
//https://github.com/opencv/opencv/issues/8304
//f.At(); f.ElemSize(); f.Ptr() are recommended instead of using pointer for memory safety,
//however, they are low performant.
T *pSrcStart = (T *)src.DataStart;
T *pSrcEnd = (T *)src.DataEnd;
T *px = (T *)x.DataStart;
T *py = (T *)y.DataStart;
T *pDst = (T *)dst.DataStart;
for (T *pSrc = pSrcStart; pSrc <= pSrcEnd; pSrc++, pDst++, px++, py++)
{
*pDst = condition(*pSrc) ? *px : *py;
}
}