Bitmap透明圖片描邊
阿新 • • 發佈：2022-04-01
1 public static byte[] ToArray(this Bitmap bitmap) 2 { 3 var lockbits = bitmap.LockBits(new Rectangle(0, 0, bitmap.Width, bitmap.Height), ImageLockMode.ReadOnly, bitmap.PixelFormat); 4 byte[] bs = new byte[lockbits.Stride * lockbits.Height]; 5 Marshal.Copy(lockbits.Scan0, bs, 0, lockbits.Stride * lockbits.Height); 6 return bs; 7 } 8 9 /// <summary> 10 /// 獲取透明邊緣座標 11 /// </summary> 12 /// <param name="bitmap"></param> 13 /// <param name="overflow">是否允許座標超出圖片範圍</param> 14 /// <returns></returns>15 public static List<Point> GetVerge(this Bitmap bitmap, bool overflow = false) 16 { 17 List<Point> ps = new List<Point>(); 18 byte[] arr = bitmap.ToArray(); 19 int w = bitmap.Width; 20 int h = bitmap.Height; 21int x = 0; 22 int y = 0; 23 int p = 3; 24 int s = w * 4; 25 26 #region x = 0 27 #region y = 0 28 if(arr[p] == 0) 29 { 30 if (arr[p + 4] > 0 || 31 arr[p + s] > 0 || arr[p + s + 4] > 0) 32 ps.Add(new Point(x, y)); 33 } 34 else if (overflow) 35 { 36 ps.Add(new Point(-1, -1)); 37 ps.Add(new Point(0, -1)); 38 ps.Add(new Point(1, -1)); 39 ps.Add(new Point(-1, 0)); 40 ps.Add(new Point(-1, 1)); 41 } 42 #endregion 43 #region 0<y<h-1 44 for (y = 1; y < h - 1; y++) 45 { 46 p = 3 + s * y; 47 if(arr[p] == 0) 48 { 49 if (arr[p - s] > 0 || arr[p - s + 4] > 0 || 50 arr[p + 4] > 0 || 51 arr[p + s] > 0 || arr[p + s + 4] > 0) 52 ps.Add(new Point(x, y)); 53 } 54 else if (overflow) 55 { 56 ps.Add(new Point(-1, y - 1)); 57 ps.Add(new Point(-1, y)); 58 ps.Add(new Point(-1, y + 1)); 59 } 60 } 61 #endregion 62 #region y = h - 1 63 p = 3 + s * y; 64 if (arr[p] == 0) 65 { 66 if (arr[p - s] > 0 || arr[p - s + 4] > 0 || 67 arr[p + 4] > 0) 68 ps.Add(new Point(x, y)); 69 } 70 else if (overflow) 71 { 72 ps.Add(new Point(-1, y - 1)); 73 ps.Add(new Point(-1, y)); 74 ps.Add(new Point(-1, y + 1)); 75 ps.Add(new Point(0, y + 1)); 76 ps.Add(new Point(1, y + 1)); 77 } 78 #endregion 79 #endregion 80 81 #region 0<x<w-1 82 for (x = 1; x < w - 1; x++) 83 { 84 #region y = 0 85 y = 0; 86 p = x * 4 + 3; 87 if (arr[p] == 0) 88 { 89 if (arr[p - 4] > 0 || arr[p + 4] > 0 || 90 arr[p + s - 4] > 0 || arr[p + s] > 0 || arr[p + s + 4] > 0) 91 ps.Add(new Point(x, y)); 92 } 93 else if (overflow) 94 { 95 ps.Add(new Point(x - 1, y - 1)); 96 ps.Add(new Point(x, y - 1)); 97 ps.Add(new Point(x + 1, y - 1)); 98 } 99 #endregion 100 #region 0<y<h-1 101 for (y = 1; y < h - 1; y++) 102 { 103 p = x * 4 + 3 + s * y; 104 if (arr[p] == 0) 105 { 106 if (arr[p - s - 4] > 0 || arr[p - s] > 0 || arr[p - s + 4] > 0 || 107 arr[p - 4] > 0 || arr[p + 4] > 0 || 108 arr[p + s - 4] > 0 || arr[p + s] > 0 || arr[p + s + 4] > 0) 109 ps.Add(new Point(x, y)); 110 } 111 } 112 #endregion 113 #region y = h - 1 114 p = x * 4 + 3 + s * y; 115 if (arr[p] == 0) 116 { 117 if (arr[p - s - 4] > 0 || arr[p - s] > 0 || arr[p - s + 4] > 0 || 118 arr[p - 4] > 0 || arr[p + 4] > 0) 119 ps.Add(new Point(x, y)); 120 } 121 else if (overflow) 122 { 123 ps.Add(new Point(x - 1, y + 1)); 124 ps.Add(new Point(x, y + 1)); 125 ps.Add(new Point(x + 1, y + 1)); 126 } 127 #endregion 128 } 129 #endregion 130 131 #region x = w - 1 132 #region y = 0 133 x = w - 1; 134 y = 0; 135 p = x * 4 + 3; 136 if (arr[p] == 0) 137 { 138 if (arr[p - 4] > 0 || 139 arr[p + s - 4] > 0 || arr[p + s] > 0) 140 ps.Add(new Point(x, y)); 141 } 142 else if (overflow) 143 { 144 ps.Add(new Point(x - 1, y - 1)); 145 ps.Add(new Point(x, y - 1)); 146 ps.Add(new Point(x + 1, y - 1)); 147 ps.Add(new Point(x + 1, y)); 148 ps.Add(new Point(x + 1, y + 1)); 149 } 150 #endregion 151 #region 0<y<h-1 152 for (y = 1; y < h - 1; y++) 153 { 154 p = x * 4 + 3 + s * y; 155 if (arr[p] == 0) 156 { 157 if (arr[p - s - 4] > 0 || arr[p - s] > 0 || 158 arr[p - 4] > 0 || 159 arr[p + s - 4] > 0 || arr[p + s] > 0) 160 ps.Add(new Point(x, y)); 161 } 162 else if (overflow) 163 { 164 ps.Add(new Point(x + 1, y - 1)); 165 ps.Add(new Point(x + 1, y)); 166 ps.Add(new Point(x + 1, y + 1)); 167 } 168 } 169 #endregion 170 #region y = h - 1 171 p = x * 4 + 3 + s * y; 172 if (arr[p] == 0) 173 { 174 if (arr[p - s - 4] > 0 || arr[p - s] > 0 || 175 arr[p - 4] > 0) 176 ps.Add(new Point(x, y)); 177 } 178 else if (overflow) 179 { 180 ps.Add(new Point(x + 1, y - 1)); 181 ps.Add(new Point(x + 1, y)); 182 ps.Add(new Point(x - 1, y + 1)); 183 ps.Add(new Point(x, y + 1)); 184 ps.Add(new Point(x + 1, y + 1)); 185 } 186 #endregion 187 #endregion 188 return ps; 189 } 190 191 /// <summary> 192 /// 獲取透明邊緣座標,返回只有描邊的圖片 193 /// </summary> 194 /// <param name="bitmap"></param> 195 /// <param name="overflow">是否允許座標超出圖片範圍</param> 196 /// <returns></returns> 197 public static byte[] GetVerge1(this Bitmap bitmap, bool overflow = false) 198 { 199 int w = overflow ? bitmap.Width + 2 : bitmap.Width; 200 int h = overflow ? bitmap.Height + 2 : bitmap.Height; 201 int s = w * 4; 202 byte[] bs = new byte[s * h]; 203 List<Point> ps = bitmap.GetVerge(overflow); 204 for (int i = 0; i < ps.Count; i++) 205 { 206 int x = overflow ? ps[i].X + 1 : ps[i].X; 207 int y = overflow ? ps[i].Y + 1 : ps[i].Y; 208 bs[x * 4 + s * y + 1] = 255; 209 bs[x * 4 + s * y + 3] = 255; 210 } 211 return bs; 212 }