OpenCvSharp图像灰度直方图（BGR、HSV、Lab多通道及单通道的灰度直方图
）
项目概述
项目实现了基于OpenCvSharp实现了BGR、HSV、Lab多通道及单通道的灰度直方图，包含了HSV和Lab的转换，及使用chart控件绘制直方图，可将打开后的图片处理后并保存到本地磁盘。
源代码在本文底部
1基础步骤和界面设计
1.1引用using OpenCvSharp;using OpenCvSharp.Extensions;
1.2将Picturebox、Label、Button等控件进行布局、改名、调整形状和字体，形成如下界面：
2功能实现
2.1初始化变量
Mat Img1 = new Mat();//用 Mat类定义图片1
Mat Img2 = new Mat();//用 Mat类定义图片2
Mat ImgCvt = new Mat();
Bitmap bitmap;//Bitmap类定义picturebox2要显示的图片
string pathname;//定义图片打开路径
2.2图表参数设置
private void chart_load()//设置图表参数
{
chart1.Series.Clear();
chart1.ChartAreas[0].AxisX.Title = "灰度";
chart1.ChartAreas[0].AxisX.TitleFont =new Font("宋体",15f) ;
chart1.ChartAreas[0].AxisX.TitleForeColor = Color.Red;
chart1.ChartAreas[0].AxisX.TitleForeColor = System.Drawing.Color.Crimson;
chart1.ChartAreas[0].AxisY.Title = "个数";
chart1.ChartAreas[0].AxisY.TitleFont = new Font("宋体", 15f);
chart1.ChartAreas[0].AxisY.TitleForeColor = Color.Blue;
chart1.ChartAreas[0].AxisY.TitleForeColor = System.Drawing.Color.Crimson;
chart1.ChartAreas[0].AxisY.TextOrientation = TextOrientation.Horizontal;
}
2.3 HSV或Lab转换及三通道的直方图
private void button20_Click(object sender, EventArgs e)
{
if (pictureBox1.Image == null)//判断图片是否已打开
{
MessageBox.Show("没有打开图片");
return;
}
Mat src = Cv2.ImRead(pathname);//读取路径下的图片
Cv2.CvtColor(src, src, ColorConversionCodes.BGR2HSV);//
bitmap = BitmapConverter.ToBitmap(src); //把Mat格式的图片转换成Bitmap
pictureBox2.Image = bitmap;
chart1.Series.Clear();//清空cShart
Series H = new Series("H");//H通道
Series S = new Series("S");//S通道
Series V= new Series("V");//V通道
Mat[] picturechannel = new Mat[3];
Cv2.Split(src, out picturechannel);
int[] histSize = {
256 };
Rangef[] histRange = {
new Rangef(0, 256) }; //the upper boundary is exclusive
bool uniform = true, accumulate = false;
Mat channel1 = new Mat();
Mat channel2 = new Mat();
Mat channel3 = new Mat();
Cv2.CalcHist(picturechannel, new int[] {
0 }, null, channel1, 1, histSize, histRange, uniform, accumulate);
Cv2.CalcHist(picturechannel, new int[] {
1 }, null, channel2, 1, histSize, histRange, uniform, accumulate);
Cv2.CalcHist(picturechannel, new int[] {
2 }, null, channel3, 1, histSize, histRange, uniform, accumulate);
for (int i = 1; i < histSize[0]; i++)
{
H.Points.AddXY(i, Math.Round(channel1.At<float>(i - 1)));
S.Points.AddXY(i, Math.Round(channel2.At<float>(i - 1)));
V.Points.AddXY(i, Math.Round(channel3.At<float>(i - 1)));
}
//绘制曲线
chart1.Series.Add(H);
chart1.Series.Add(S);
chart1.Series.Add(V);
}
2.4单通道法
private void button7_Click(object sender, EventArgs e)
{
if (pictureBox1.Image == null)//判断图片是否已打开
{
MessageBox.Show("没有打开图片");
return;
}
Mat src = Cv2.ImRead(pathname);//读取路径下的图片
bitmap = BitmapConverter.ToBitmap(src); //把Mat格式的图片转换成Bitmap
Mat dst = new Mat(src.Size(), MatType.CV_8U);
int height = src.Rows;
int width = src.Cols;
for (int row = 0; row < height; row++)
{
for (int col = 0; col < width; col++)
{
dst.At<byte>(row, col) = (byte)src.At<Vec3b>(row, col)[0];
}
}
bitmap = BitmapConverter.ToBitmap(dst); //把Mat格式的图片转换成Bitmap
pictureBox2.Image = bitmap;
chart1.Series.Clear();//清空chart
Series B = new Series("B");//B通道
B.Color=Color.Gray;
Mat[] picturechannel = new Mat[3];
Cv2.Split(src, out picturechannel);
int[] histSize = {
256 };
Rangef[] histRange = {
new Rangef(0, 256) }; //the upper boundary is exclusive
bool uniform = true, accumulate = false;
Mat channel1 = new Mat();
Cv2.CalcHist(picturechannel, new int[] {
0 }, null, channel1, 1, histSize, histRange, uniform, accumulate);
for (int i = 1; i < histSize[0]; i++)
{
B.Points.AddXY(i, Math.Round(channel1.At<float>(i - 1)));
}
//绘制曲线
chart1.Series.Add(B);
}
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源代码：https://download.csdn.net/download/sunsoldeir1/87254081
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