ObjectMap.cs

using IdApp.Cv.Basic;
using System;
using System.Collections.Generic;
 
namespace IdApp.Cv.Objects
{
    public class ObjectMap : Matrix<ushort>
    {
        private readonly Dictionary<ushort, ObjectInformation> objectsById = new Dictionary<ushort, ObjectInformation>();
        private readonly ObjectInformation[] objects;
        private readonly IMatrix image;
 
        public ObjectMap(Matrix<float> M, float Threshold)
            : base(M.Width, M.Height)
        {
            this.image = this.Image;
 
            int y, h = M.Height;
            int x, w = M.Width;
            int SrcIndex = M.Start;
            int SrcSkip = M.Skip;
            int DestIndex = 0;
            float[] Src = M.Data;
            ushort[] Dest = this.Data;
            float v;
            ObjectInformation Info;
            ushort Obj;
 
            for (y = 0; y < h; y++, SrcIndex += SrcSkip)
            {
                for (x = 0; x < w; x++, DestIndex++)
                {
                    v = Src[SrcIndex++];
                    if (v >= Threshold)
                    {
                        Obj = Dest[DestIndex];
                        if (Obj == 0)
                        {
                            Obj = (ushort)this.objectsById.Count;
                            Info = new ObjectInformation(Obj, x, y, this);
                            this.objectsById[Obj] = Info;
                            this.FloodFill(x, y, M, Threshold, Info);
                        }
                    }
                }
            }
 
            this.objects = new ObjectInformation[this.objectsById.Count];
            this.objectsById.Values.CopyTo(this.objects, 0);
        }
 
        private void FloodFill(int x, int y, Matrix<float> M, float Threshold, ObjectInformation Info)
        {
            int SrcIndex = M.StartIndex(0, y);
            int DestIndex = this.StartIndex(0, y);
            float[] Src = M.Data;
            ushort[] Dest = this.Data;
            int x1 = x;
            int x2 = x;
            int w = M.Width;
            int h = M.Height - 1;
            int SrcRow = M.RowSize;
            int DestRow = this.RowSize;
            ushort Nr = (ushort)(Info.Nr + 1);
            int si, di;
 
            while (x1 > 0 && Src[SrcIndex + x1 - 1] >= Threshold && Dest[DestIndex + x1 - 1] == 0)
                x1--;
 
            while (x2 < w - 1 && Src[SrcIndex + x2 + 1] >= Threshold && Dest[DestIndex + x2 + 1] == 0)
                x2++;
 
            Info.AddPixels(x1, x2, y);
 
            x = x1;
            di = DestIndex + x;
            Dest[di] = (ushort)(Nr | 0x8000);
            x++;
            di++;
 
            while (x < x2)
            {
                Dest[di] = Nr;
                x++;
                di++;
            }
 
            Dest[di] = (ushort)(Nr | 0x8000);
 
            for (x = x1, si = SrcIndex + x, di = DestIndex + x; x <= x2; x++, si++, di++)
            {
                if (y > 0)
                {
                    if (Src[si - SrcRow] >= Threshold)
                    {
                        if (Dest[di - DestRow] == 0)
                            this.FloodFill(x, y - 1, M, Threshold, Info);
                    }
                    else
                        Dest[di] |= 0x4000;
                }
 
                if (y < h)
                {
                    if (Src[si + SrcRow] >= Threshold)
                    {
                        if (Dest[di + DestRow] == 0)
                            this.FloodFill(x, y + 1, M, Threshold, Info);
                    }
                    else
                        Dest[di] |= 0x4000;
                }
            }
        }
 
 
        public ObjectMap(Matrix<int> M, int Threshold)
            : base(M.Width, M.Height)
        {
            this.image = this.Image;
 
            int y, h = M.Height;
            int x, w = M.Width;
            int SrcIndex = M.Start;
            int SrcSkip = M.Skip;
            int DestIndex = 0;
            int[] Src = M.Data;
            ushort[] Dest = this.Data;
            int v;
            ObjectInformation Info;
            ushort Obj;
 
            for (y = 0; y < h; y++, SrcIndex += SrcSkip)
            {
                for (x = 0; x < w; x++, DestIndex++)
                {
                    v = Src[SrcIndex++];
                    if (v >= Threshold)
                    {
                        Obj = Dest[DestIndex];
                        if (Obj == 0)
                        {
                            Obj = (ushort)this.objectsById.Count;
                            Info = new ObjectInformation(Obj, x, y, this);
                            this.objectsById[Obj] = Info;
                            this.FloodFill(x, y, M, Threshold, Info);
                        }
                    }
                }
            }
 
            this.objects = new ObjectInformation[this.objectsById.Count];
            this.objectsById.Values.CopyTo(this.objects, 0);
        }
 
        private void FloodFill(int x, int y, Matrix<int> M, int Threshold, ObjectInformation Info)
        {
            int SrcIndex = M.StartIndex(0, y);
            int DestIndex = this.StartIndex(0, y);
            int[] Src = M.Data;
            ushort[] Dest = this.Data;
            int x1 = x;
            int x2 = x;
            int w = M.Width;
            int h = M.Height - 1;
            int SrcRow = M.RowSize;
            int DestRow = this.RowSize;
            ushort Nr = (ushort)(Info.Nr + 1);
            int si, di;
 
            while (x1 > 0 && Src[SrcIndex + x1 - 1] >= Threshold && Dest[DestIndex + x1 - 1] == 0)
                x1--;
 
            while (x2 < w - 1 && Src[SrcIndex + x2 + 1] >= Threshold && Dest[DestIndex + x2 + 1] == 0)
                x2++;
 
            Info.AddPixels(x1, x2, y);
 
            x = x1;
            di = DestIndex + x;
            Dest[di] = (ushort)(Nr | 0x8000);
            x++;
            di++;
 
            while (x < x2)
            {
                Dest[di] = Nr;
                x++;
                di++;
            }
 
            Dest[di] = (ushort)(Nr | 0x8000);
 
            for (x = x1, si = SrcIndex + x, di = DestIndex + x; x <= x2; x++, si++, di++)
            {
                if (y > 0)
                {
                    if (Src[si - SrcRow] >= Threshold)
                    {
                        if (Dest[di - DestRow] == 0)
                            this.FloodFill(x, y - 1, M, Threshold, Info);
                    }
                    else
                        Dest[di] |= 0x4000;
                }
 
                if (y < h)
                {
                    if (Src[si + SrcRow] >= Threshold)
                    {
                        if (Dest[di + DestRow] == 0)
                            this.FloodFill(x, y + 1, M, Threshold, Info);
                    }
                    else
                        Dest[di] |= 0x4000;
                }
            }
        }
 
        public IMatrix Image => this.image;
 
        public int NrObjects => this.objectsById.Count;
 
        public ObjectInformation this[ushort Nr] => this.objectsById[Nr];
 
        internal Point[] FindContour(int X0, int Y0, int Nr)
        {
            List<Point> Result = new List<Point>();
            LinkedList<Rec> History = new LinkedList<Rec>();
            Point P;
            int Dir = 0;    // Right
            int x = X0;
            int y = Y0;
            int i;
            int Index = this.StartIndex(X0, Y0);
            int Index1;
            int RowSize = this.RowSize;
            int w = this.Width;
            int h = this.Height;
            ushort[] Data = this.Data;
            ushort v;
            int dx, dy;
            int x1, y1;
 
            Nr++;
 
            Result.Add(P = new Point(X0, Y0));
            History.AddLast(new Rec(P, Dir));
            Data[Index] &= 0x3fff;
 
            while (true)
            {
                for (i = 0; i < 8; i++)
                {
                    dx = DirectionX[Dir];
                    dy = DirectionY[Dir];
 
                    x1 = x + dx;
                    y1 = y + dy;
 
                    if (x1 >= 0 && x1 < w && y1 >= 0 && y1 < h)
                    {
                        Index1 = Index + dx + dy * RowSize;
                        v = Data[Index1];
                        if ((v & 0x3fff) == Nr && (v & 0xc000) > 0)
                        {
                            x = x1;
                            y = y1;
                            Index = Index1;
                            Result.Add(P = new Point(x, y));
                            History.AddLast(new Rec(P, Dir));
                            Data[Index] &= 0x3fff;
                            break;
                        }
                    }
 
                    Dir = (Dir + 1) & 7;
                }
 
                if (i >= 8)
                {
                    if (History.Last is null)
                        break;
                    else
                    {
                        Rec Rec = History.Last.Value;
                        History.RemoveLast();
                        x = Rec.P.X;
                        y = Rec.P.Y;
                        Dir = Rec.Dir;
                        Index = this.StartIndex(x, y);
                    }
                }
            }
 
            return Result.ToArray();
        }
#pragma warning disable IDE1006 // Naming Styles
        private static readonly int[] DirectionX = new int[] { 1, 1, 0, -1, -1, -1, 0, 1 };
        private static readonly int[] DirectionY = new int[] { 0, -1, -1, -1, 0, 1, 1, 1 };
#pragma warning restore IDE1006 // Naming Styles
 
        private class Rec
        {
            public Rec(Point P, int Dir)
            {
                this.P = P;
                this.Dir = Dir;
            }
 
            public Point P;
            public int Dir;
        }
 
        public ObjectInformation[] Objects => this.objects;
 
        public IMatrix Extract(params ushort[] Nrs)
        {
            return this.Extract(Nrs, this.image);
        }
 
        public IMatrix Extract(ushort[] Nrs, IMatrix Source)
        {
            if (Source.Width != this.Width || Source.Height != this.Height)
                throw new ArgumentOutOfRangeException(nameof(Source));
 
            ObjectInformation[] Infos = this.GetInfo(Nrs);
 
            if (Source is Matrix<float> M)
                return this.Extract<float>(Nrs, M, Infos, float.MinValue);
            else if (Source is Matrix<int> M2)
                return this.Extract<int>(Nrs, M2, Infos, int.MinValue);
            else if (Source is Matrix<uint> M3)
                return this.Extract<uint>(Nrs, M3, Infos, 0);
            else if (Source is Matrix<byte> M4)
                return this.Extract<byte>(Nrs, M4, Infos, 0);
            else
                throw new InvalidOperationException("Underlying image type not supported.");
        }
 
        private ObjectInformation[] GetInfo(ushort[] Nrs)
        {
            int i, c = Nrs.Length;
            ObjectInformation[] Infos = new ObjectInformation[c];
 
            for (i = 0; i < c; i++)
            {
                if (!this.objectsById.TryGetValue(Nrs[i], out ObjectInformation Info))
                    throw new ArgumentOutOfRangeException(nameof(Nrs));
 
                Infos[i] = Info;
            }
 
            return Infos;
        }
 
        public Matrix<T> Extract<T>(ushort[] Nrs, Matrix<T> Source)
            where T : struct
        {
            if (Source.Width != this.Width || Source.Height != this.Height)
                throw new ArgumentOutOfRangeException(nameof(Source));
 
            ObjectInformation[] Infos = this.GetInfo(Nrs);
 
            return this.Extract<T>(Nrs, Source, Infos, default);
        }
 
        private Matrix<T> Extract<T>(ushort[] Nrs, Matrix<T> Image, ObjectInformation[] Objects, T BackgroundValue)
            where T : struct
        {
            int x, y, c = Nrs.Length;
            if (c != Objects.Length)
                throw new ArgumentException("Array size mismatch.", nameof(Objects));
 
            if (c == 0)
                return new Matrix<T>(1, 1);
 
            int SrcX1 = Objects[0].MinX;
            int SrcY1 = Objects[0].MinY;
            int SrcX2 = Objects[0].MaxX;
            int SrcY2 = Objects[0].MaxY;
            y = Objects[0].Nr;
 
            for (x = 1; x < c; x++)
            {
                ObjectInformation Info = Objects[x];
 
                if (Info.MinX < SrcX1)
                    SrcX1 = Info.MinX;
 
                if (Info.MaxX > SrcX2)
                    SrcX2 = Info.MaxX;
 
                if (Info.MinY < SrcY1)
                    SrcY1 = Info.MinY;
 
                if (Info.MaxY > SrcY2)
                    SrcY2 = Info.MaxY;
 
                if (Info.Nr > y)
                    y = Info.Nr;
            }
 
            bool[] Included = new bool[y + 2];
            for (x = 0; x < c; x++)
                Included[Objects[x].Nr + 1] = true;
 
            c = y + 2;
 
            int w = SrcX2 - SrcX1 + 1;
            int h = SrcY2 - SrcY1 + 1;
            int SrcIndex = Image.StartIndex(SrcX1, SrcY1);
            int SrcSkip = Image.Skip + Image.Width - w;
            int MaskIndex = this.StartIndex(SrcX1, SrcY1);
            int MaskSkip = Image.Width - w;
            ushort i;
            Matrix<T> Result = new Matrix<T>(w, h);
            ushort[] Mask = this.Data;
            T[] Src = Image.Data;
            T[] Dest = Result.Data;
            int DestIndex = 0;
 
            for (y = SrcY1; y <= SrcY2; y++, SrcIndex += SrcSkip, MaskIndex += MaskSkip)
            {
                for (x = SrcX1; x <= SrcX2; x++, SrcIndex++)
                {
                    i = Mask[MaskIndex++];
                    i &= 0x3fff;
                    Dest[DestIndex++] = i < c && Included[i] ? Src[SrcIndex] : BackgroundValue;
                }
            }
 
            return Result;
        }
    }
}