Integral.cs

namespace IdApp.Cv.Statistics
{
    public static partial class StatisticsOperations
    {
        public static Matrix<float> Integral(this Matrix<float> M)
        {
            int y, h = M.Height;
            int x, w = M.Width;
            int SrcIndex = M.Start;
            int SrcSkip = M.Skip;
            int DestIndex = 0;
            float[] SrcData = M.Data;
            float[] Dest = new float[w * h];
            float RowSum;
 
            Dest[DestIndex++] = SrcData[SrcIndex++];
            for (x = 1; x < w; x++, DestIndex++)
                Dest[DestIndex] = Dest[DestIndex - 1] + SrcData[SrcIndex++];
 
            SrcIndex += SrcSkip;
 
            for (y = 1; y < h; y++, SrcIndex += SrcSkip)
            {
                RowSum = SrcData[SrcIndex++];
                Dest[DestIndex] = Dest[DestIndex - w] + RowSum;
                DestIndex++;
 
                for (x = 1; x < w; x++, DestIndex++)
                {
                    RowSum += SrcData[SrcIndex++];
                    Dest[DestIndex] = Dest[DestIndex - w] + RowSum;
                }
            }
 
            return new Matrix<float>(w, h, Dest);
        }
 
        public static Matrix<long> Integral(this Matrix<int> M)
        {
            int y, h = M.Height;
            int x, w = M.Width;
            int SrcIndex = M.Start;
            int SrcSkip = M.Skip;
            int DestIndex = 0;
            int[] SrcData = M.Data;
            long[] Dest = new long[w * h];
            long RowSum;
 
            Dest[DestIndex++] = SrcData[SrcIndex++];
            for (x = 1; x < w; x++, DestIndex++)
                Dest[DestIndex] = Dest[DestIndex - 1] + SrcData[SrcIndex++];
 
            SrcIndex += SrcSkip;
 
            for (y = 1; y < h; y++, SrcIndex += SrcSkip)
            {
                RowSum = SrcData[SrcIndex++];
                Dest[DestIndex] = Dest[DestIndex - w] + RowSum;
                DestIndex++;
 
                for (x = 1; x < w; x++, DestIndex++)
                {
                    RowSum += SrcData[SrcIndex++];
                    Dest[DestIndex] = Dest[DestIndex - w] + RowSum;
                }
            }
 
            return new Matrix<long>(w, h, Dest);
        }
    }
}