//输入：原图和圆心信息(圆心位置和半径)，输出：直线所在区域（包含较少噪声的圆环）
public myPicture doFind(myPicture input, circle cir)
{
int width = input.width, height = input.height;
Bitmap res = new Bitmap(width, height);
int x = (int)cir.x, y = (int)cir.y;
//截取圆环为0.15*半径——0.5*半径
int maxr = (int)(0.5 * cir.r), minr = (int)(0.15 * cir.r);
for (int i = 0; i < width; i++)
{
for (int j = 0; j < height; j++)
{
res.SetPixel(i, j, Color.FromArgb(255, 255, 255));
}
}
//将0.15*半径——0.5*半径区域赋值成原图像内容
for (int i = -maxr; i <= maxr; i++)
{
int pos1 = -1;
for (int j = 0; j < height; j++)
{
if (i * i + j * j <= maxr * maxr)
{
pos1 = j;
break;
}
}
int pos2 = -1;
for (int j = height - 1; j >= 0; j--)
{
if (i * i + j * j <= maxr * maxr)
{
pos2 = j;
break;
}
}
if (pos1 == -1)
{
continue;
}
for (int j = pos1; j <= pos2; j++)
{
if (i * i + j * j < minr * minr)
{
continue;
}
res.SetPixel(x + i, y + j, input.picture.GetPixel(x + i, y + j));
res.SetPixel(x + i, y - j, input.picture.GetPixel(x + i, y - j));
}
}
return(new myPicture(res));
}
//函数功能：确定仪表盘指针的方向向量
//输入：二值图像input，直线方程ret，仪表盘中心o
//输出：仪表盘指针上的某一个点
public myPair doFind(myPicture input, line ret, circle o)
{
if (Math.Abs(ret.B) < 0.000001)
{
return(new myPair((int)o.x, 0));
}
int MAGIC = (int)(input.width * 0.18);
int cnt1 = 0, cnt2 = 0;
double K = -ret.A / ret.B;
double B = -ret.C / ret.B;
for (int dx = 1; dx <= MAGIC; ++dx)
{
double x = o.x + dx;
double y = K * x + B;
int xx = (int)x;
int yy = (int)y;
if (xx + 2 >= input.width || xx - 2 < 0)
{
break;
}
if (yy + 2 >= input.height || yy - 2 < 0)
{
break;
}
for (int i = -2; i <= 2; ++i)
{
for (int j = -2; j <= 2; ++j)
{
if (input.grayDegree[(int)(x + i), (int)(y + j)] == 255)
{
cnt1++;
}
}
}
}
for (int dx = 1; dx <= MAGIC; ++dx)
{
double x = o.x - dx;
double y = K * x + B;
int xx = (int)x;
int yy = (int)y;
if (xx + 2 >= input.width || xx - 2 < 0)
{
break;
}
if (yy + 2 >= input.height || yy - 2 < 0)
{
break;
}
for (int i = -2; i <= 2; ++i)
{
for (int j = -2; j <= 2; ++j)
{
if (input.grayDegree[(int)(x + i), (int)(y + j)] == 255)
{
cnt2++;
}
}
}
}
if (cnt1 > cnt2)
{
double x = o.x + MAGIC;
double y = K * x + B;
return(new myPair((int)x, (int)y));
}
else
{
double x = o.x - MAGIC;
double y = K * x + B;
return(new myPair((int)x, (int)y));
}
}
private double angle(myPair left, myPair right, circle o)
{
return(Math.Acos(((left.x * right.x - o.x * (left.x + right.x) + o.x * o.x) + (left.y * right.y - o.y * (left.y + right.y) + o.y * o.y)) / (Math.Sqrt((left.x - o.x) * (left.x - o.x) + (left.y - o.y) * (left.y - o.y)) * Math.Sqrt((right.x - o.x) * (right.x - o.x) + (right.y - o.y) * (right.y - o.y)))));
}