/// <summary>
/// 切割图片 X坐标
/// </summary>
/// <param name="x">图片</param>
/// <param name="s">X开始坐标</param>
/// <param name="e">X结束坐标</param>
/// <returns></returns>
public static EffImage CutH(EffImage x, int s, int e)
{
if (e - s <= 0)
{
return(null);
}
if (s > 1)
{
s -= 1;
}
if (e < x.Width - 1)
{
e += 1;
}
EffImage rt = White(e - s, x.Height);
for (int i = s; i < e; i++)
{
for (int j = 0; j < x.Height; j++)
{
rt.Set(i - s, j, x.At(i, j));
}
}
return(rt);
}
/// <summary>
/// EffImage填充边距
/// </summary>
/// <param name="src">源图</param>
/// <param name="w">目标宽</param>
/// <param name="h">目标高</param>
/// <returns></returns>
public static EffImage Padding(EffImage src, int w, int h)
{
using (var bmp = src.Origin)
{
return(new EffImage(Padding(bmp, w, h)));
}
}
/// <summary>
/// Y方向切割图片
/// </summary>
/// <param name="x"></param>
/// <param name="s"></param>
/// <param name="e"></param>
/// <returns></returns>
public static EffImage CutV(EffImage x, int s, int e)
{
if (e - s <= 0)
{
return(null);
}
if (s > 1)
{
s -= 1;
}
if (e < x.Height - 1)
{
e += 1;
}
EffImage rt = White(x.Width, e - s);
for (int j = s; j < e; j++)
{
for (int i = 0; i < x.Width; i++)
{
rt.Set(i, j - s, x.At(i, j));
}
}
return(rt);
}
public object Clone()
{
var img = EffImage.White(Width, Height);
img.pixels = this.pixels.Clone() as Color[, ];
return(img);
}
/// <summary>
/// 旋转图片
/// </summary>
/// <param name="degree">度数</param>
/// <returns></returns>
public EffImage Rotate(int degree)
{
EffImage rtImg = White(Width, Height);
var org = CutV(CutH(this, Left, Right), Top, Bottom);
var bmp = org.Origin;
var rwid = (org.width + org.height) * 2;
Bitmap r = new Bitmap(rwid, rwid);
Graphics g = Graphics.FromImage(r);
g.Clear(Color.White);
g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.None;
g.RotateTransform(degree);
g.DrawImage(bmp, new Point((rwid / 2) - (org.width / 2), (rwid / 2) - (org.height / 2)));
return(new EffImage(r).ValidArea);
}
/// <summary>
/// 位图填充
/// </summary>
/// <param name="src">原图</param>
/// <param name="w">目标宽</param>
/// <param name="h">目标高</param>
/// <returns></returns>
public static Bitmap Padding(Bitmap src, int w, int h)
{
var eimg = new EffImage(src);
Bitmap rt = new Bitmap(w, h);
Graphics g = Graphics.FromImage(rt);
g.Clear(Color.White);
int left = eimg.Left;
int right = eimg.Right;
int top = eimg.Top;
int bot = eimg.Bottom;
int pwid = right - left;
int phei = bot - top;
int padleft = (w - pwid) / 2 - 1;
int padright = (h - phei) / 2 - 1;
var sr = CutV(CutH(eimg, left, right), top, bot);
g.DrawImage(sr.Origin, new Point(padleft, padright));
g.Dispose();
return(rt);
}
/// <summary>
/// 某论文上的细化算法OpenCV改EffImage版
/// </summary>
/// <param name="iter"></param>
private static void thiniter(byte iter, EffImage img)
{
int convertColor(Color c)
{
return(c.R < 100 ? 1 : 0);
}
for (int i = 1; i < img.Width - 1; i++)
{
for (int j = 1; j < img.Height - 1; j++)
{
int p2 = convertColor(img.At(i - 1, j));
int p3 = convertColor(img.At(i - 1, j + 1));
int p4 = convertColor(img.At(i, j + 1));
int p5 = convertColor(img.At(i + 1, j + 1));
int p6 = convertColor(img.At(i + 1, j));
int p7 = convertColor(img.At(i + 1, j - 1));
int p8 = convertColor(img.At(i, j - 1));
int p9 = convertColor(img.At(i - 1, j - 1));
int A = Convert.ToInt32((p2 == 0 && p3 == 1)) + Convert.ToInt32((p3 == 0 && p4 == 1)) +
Convert.ToInt32((p4 == 0 && p5 == 1)) + Convert.ToInt32((p5 == 0 && p6 == 1)) +
Convert.ToInt32((p6 == 0 && p7 == 1)) + Convert.ToInt32((p7 == 0 && p8 == 1)) +
Convert.ToInt32((p8 == 0 && p9 == 1)) + Convert.ToInt32((p9 == 0 && p2 == 1));
int B = p2 + p3 + p4 + p5 + p6 + p7 + p8 + p9;
int m1 = iter == 0 ?
(p2 * p4 * p6) :
(p2 * p4 * p8);
int m2 = iter == 0 ?
(p4 * p6 * p8) :
(p2 * p6 * p8);
if (A == 1 && (B >= 2 && B <= 6) && m1 == 0 && m2 == 0)
{
img.Set(i, j, Color.White);
}
}
}
}
/// <summary>
/// 缩放
/// </summary>
/// <param name="img"></param>
/// <param name="w">目标宽</param>
/// <param name="h">目标高</param>
/// <param name="keepRatio">是否保持原始比例</param>
/// <returns></returns>
public static EffImage Resize(EffImage img, int w, int h, bool keepRatio = true)
{
Bitmap bmp = new Bitmap(w, h);
Graphics g = Graphics.FromImage(bmp);
g.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighQuality;
g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.None;
g.Clear(Color.White);
var src = img.Origin;
var dstRect = new Rectangle(0, 0, w, h);
var srcRect = new Rectangle(0, 0, img.width, img.height);
// 保持原始比例
if (keepRatio)
{
var wRatio = (double)img.width / (double)w;
var hRatio = (double)img.height / (double)h;
// 选一个
var r = Math.Max(wRatio, hRatio);
var dstW = img.width / r;
var dstH = img.height / r;
var padL = (w - dstW) / 2;
var padT = (h - dstH) / 2;
dstRect = new Rectangle((int)padL, (int)padT, (int)dstW, (int)dstH);
}
g.DrawImage(src, dstRect, srcRect, GraphicsUnit.Pixel);
var rt = new EffImage(bmp);
g.Flush();
g.Dispose();
src.Dispose();
bmp.Dispose();
return(rt);
}
/// <summary>
/// 去掉杂点（适合杂点/杂线粗为1）
/// NOTE: 没什么用
/// </summary>
public static void ClearNoise(this EffImage img, int MaxNearPoints)
{
Color piexl;
int nearDots = 0;
int dgGrayValue = 50;
// int XSpan, YSpan, tmpX, tmpY;
//逐点判断
for (int i = 0; i < img.Width; i++)
{
for (int j = 0; j < img.Height; j++)
{
piexl = img.At(i, j);
if (piexl.R < dgGrayValue)
{
nearDots = 0;
//判断周围8个点是否全为空
if (i == 0 || i == img.Width - 1 || j == 0 || j == img.Height - 1) //边框全去掉
{
img.Set(i, j, Color.FromArgb(255, 255, 255));
}
else
{
if (img.At(i - 1, j - 1).R < dgGrayValue)
{
nearDots++;
}
if (img.At(i, j - 1).R < dgGrayValue)
{
nearDots += 2;
}
if (img.At(i + 1, j - 1).R < dgGrayValue)
{
nearDots += 2;
}
if (img.At(i - 1, j).R < dgGrayValue)
{
nearDots++;
}
if (img.At(i + 1, j).R < dgGrayValue)
{
nearDots++;
}
if (img.At(i - 1, j + 1).R < dgGrayValue)
{
nearDots += 2;
}
if (img.At(i, j + 1).R < dgGrayValue)
{
nearDots += 2;
}
if (img.At(i + 1, j + 1).R < dgGrayValue)
{
nearDots += 2;
}
}
if (nearDots < MaxNearPoints)
{
img.Set(i, j, Color.FromArgb(255, 255, 255)); //去掉单点 && 粗细小3邻边点
}
}
else //背景
{
img.Set(i, j, Color.FromArgb(255, 255, 255));
}
}
}
}
/// <summary>
/// 边缘提取
/// </summary>
public static void Contouring(this EffImage image)
{
image.ConvolutionFilter(Laplacian3x3, 1, 0);
}
/// <summary>
/// 细化
/// </summary>
public static void Thining(this EffImage image)
{
thiniter(0, image);
thiniter(1, image);
}
/// <summary>
/// 卷积运算
/// </summary>
/// <param name="filterMatrix">矩阵</param>
/// <param name="factor">因子</param>
/// <param name="bias">偏移</param>
public void ConvolutionFilter(double[,] filterMatrix,
double factor = 1,
int bias = 0)
{
EffImage rt = EffImage.White(width, height);
double blue = 0.0;
double green = 0.0;
double red = 0.0;
int filterWidth = filterMatrix.GetLength(1);
int filterHeight = filterMatrix.GetLength(0);
int filterOffset = (filterWidth - 1) / 2;
// TODO : PADDING边角
for (int x = filterOffset; x <
Width - filterOffset; x++)
{
for (int y = filterOffset; y <
Height - filterOffset; y++)
{
blue = green = red = 0d;
for (int filterX = -filterOffset;
filterX <= filterOffset; filterX++)
{
for (int filterY = -filterOffset;
filterY <= filterOffset; filterY++)
{
var color = At(x + filterX, y + filterY);
red += color.R * filterMatrix[filterY + filterOffset, filterX + filterOffset];
green += color.G * filterMatrix[filterY + filterOffset, filterX + filterOffset];
blue += color.B * filterMatrix[filterY + filterOffset, filterX + filterOffset];
}
}
red = red * factor + bias;
green = green * factor + bias;
blue = blue * factor + bias;
if (red > 255)
{
red = 255;
}
else if (red < 0)
{
red = 0;
}
if (green > 255)
{
green = 255;
}
else if (green < 0)
{
green = 0;
}
if (blue > 255)
{
blue = 255;
}
else if (blue < 0)
{
blue = 0;
}
rt.Set(x, y, Color.FromArgb((int)red, (int)green, (int)blue));
}
}
this.pixels = rt.pixels;
}
