emgu cv 圖像三色的直方圖

結果如圖所示

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using Emgu.CV;
using Emgu.Util;
using Emgu.CV.Structure;
namespace zhifangtu
{
    public partial class Form1 : Form
    {
        Rectangle rc;
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            OpenFileDialog open = new OpenFileDialog();
            if (open.ShowDialog() == DialogResult.OK)
            {
                this.pictureBox1.Load(open.FileName);
                IntPtr mm= CvInvoke.cvLoadImage(open.FileName,Emgu.CV.CvEnum.LOAD_IMAGE_TYPE.CV_LOAD_IMAGE_COLOR);
                
                Image<Bgr,byte> ptr =new Image<Bgr,byte>(open.FileName);
                rc = CvInvoke.cvGetImageROI(ptr);

                IntPtr m1=CvInvoke.cvCreateImage(rc.Size,Emgu.CV.CvEnum.IPL_DEPTH.IPL_DEPTH_8U,1);
                IntPtr m2=CvInvoke.cvCreateImage(rc.Size,Emgu.CV.CvEnum.IPL_DEPTH.IPL_DEPTH_8U,1);
                IntPtr m3=CvInvoke.cvCreateImage(rc.Size,Emgu.CV.CvEnum.IPL_DEPTH.IPL_DEPTH_8U,1);


                CvInvoke.cvSplit(ptr,m1,m2,m3,IntPtr.Zero);//分割圖像B,G,R
                rc.Width = 512;
                rc.Height = 150;
                 IntPtr n1 = CvInvoke.cvCreateImage(rc.Size, Emgu.CV.CvEnum.IPL_DEPTH.IPL_DEPTH_8U, 1);
                 IntPtr n2 = CvInvoke.cvCreateImage(rc.Size, Emgu.CV.CvEnum.IPL_DEPTH.IPL_DEPTH_8U, 1);
                 IntPtr n3 = CvInvoke.cvCreateImage(rc.Size, Emgu.CV.CvEnum.IPL_DEPTH.IPL_DEPTH_8U, 1);
                 zhifangtu(m1, n1);//直方圖函數，對單通道圖像進行操作
                 zhifangtu(m2, n2);
                 zhifangtu(m3, n3);

                Image<Gray,byte> nnn=new Image<Gray,byte>(rc.Width,rc.Height);
                CvInvoke.cvCopy(n1,nnn,IntPtr.Zero);
                pictureBox2.Image = nnn.ToBitmap();//顯示到picturebox上
                CvInvoke.cvCopy(n2, nnn, IntPtr.Zero);
                pictureBox3.Image = nnn.ToBitmap();
                CvInvoke.cvCopy(n3, nnn, IntPtr.Zero);
                pictureBox4.Image = nnn.ToBitmap();

            }
        }
        private void zhifangtu( IntPtr yy ,IntPtr nn)
        {


            int[] hist_size = new int[1] { 256 };//建一個數組來存放直方圖數據

            IntPtr HistImg = CvInvoke.cvCreateHist(1, hist_size, Emgu.CV.CvEnum.HIST_TYPE.CV_HIST_ARRAY, null, 1);//創建了一個空的直方圖


            IntPtr[] inPtr1 = new IntPtr[1] { yy};

            CvInvoke.cvCalcHist(inPtr1, HistImg, false, System.IntPtr.Zero);//計算inPtr1指向圖像的數據，並傳入Histimg中，其中IntPtr[] inPtr1 = new IntPtr[1] { SubImg}。
               
            int i;
            float min = 0, max = 0;
            int[] idx = new int[256];
            int[] idy = new int[256];

            CvInvoke.cvGetMinMaxHistValue(HistImg, ref min, ref max, idy, idx);

            double[] temphist = new double[256];
            for (i = 0; i < 256; i++)
            {
                temphist[i] = CvInvoke.cvQueryHistValue_1D(HistImg, i);
            }

             //nn = CvInvoke.cvCreateImage(rc.Size, Emgu.CV.CvEnum.IPL_DEPTH.IPL_DEPTH_8U, 1);
            CvInvoke.cvZero(nn);
            int scale = 2;
            for (i = 0; i < 255; i++)
            {

                Point pt1 = new Point();
                Point pt2 = new Point();
                Point pt3 = new Point();
                Point pt4 = new Point();

                pt1.X = i * scale;
                pt1.Y = 64 * scale;
                pt2.X = (i + 1) * scale;
                pt2.Y = 64 * scale;
                pt3.X = (i + 1) * scale;
                pt3.Y = Convert.ToInt16((64 - (temphist[i + 1] / max) * 64) * scale);
                pt4.X = i * scale;
                pt4.Y = Convert.ToInt16((64 - (temphist[i] / max) * 64) * scale);

                int numPts = 5;
                Point[] pts = new Point[5];
                pts[0] = pt1;
                pts[1] = pt2;
                pts[2] = pt3;
                pts[3] = pt4;
                pts[4] = pt1;
                Rgb mmmm = new Rgb();
                mmmm.Red = 255;
                mmmm.Blue = 0;
                mmmm.Green = 0;
                int uu = 1;
                CvInvoke.cvFillConvexPoly(nn, pts, numPts, mmmm.MCvScalar, Emgu.CV.CvEnum.LINE_TYPE.CV_AA, uu);

            }
           
        }
    }
}