画矩形

 画四边形

 保存标注图片

保存标注信息

 代码

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 System.Drawing.Imaging;
using System.Drawing.Drawing2D;
using System.IO;

namespace lxw_Lable
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private SolidBrush fill_brush = new SolidBrush(Color.FromArgb(100, Color.White));
        private Pen line_color = new Pen(new SolidBrush(Color.Red), 2);
        private Pen pen_yellow = new Pen(new SolidBrush(Color.Yellow), 2);
        private Pen pen_red = new Pen(new SolidBrush(Color.Red), 2);
        private Graphics draw_paint, merge_paint;//中间画板
        private Image tmp_bitmap;//用来保存绘图痕迹
        List<Point> polyPoints = null;//存储绘制多边形的点集
        List<List<Point>> ltPoly = new List<List<Point>>();//图形信息,最终保存和导出
        Rectangle rectA;//存储要用于绘图的矩形
        Image bg_image;//背景图片
        Point start;  //起始点
        Point end;   //结束点
        bool need_draw_tmp;   //在MouseMove事件中判断是否绘制矩形框
        string action_type = "";//绘图动作类型
        bool is_first_down = true;//判断是否第一次按下鼠标

        private void button1_Click(object sender, EventArgs e)
        {
            OpenFileDialog ofd = new OpenFileDialog();
            ofd.Title = "请选择图片";
            ofd.Filter = "jpg图片|*.JPG|jpeg图片|*.JPEG|gif图片|*.GIF|png图片|*.PNG";//文件类型
            ofd.Multiselect = false;
            if (ofd.ShowDialog() == DialogResult.OK)
            {
                string image_path = ofd.FileName;
                //中间画布
                tmp_bitmap = new Bitmap(image_path);
                //创建空白画板
                draw_paint = Graphics.FromImage(tmp_bitmap);
                bg_image = Image.FromFile(image_path);
                pictureBox1.Image = bg_image;
            }
        }

        private void button2_Click(object sender, EventArgs e)
        {
            if (pictureBox1.Image == null)
            {
                return;
            }
            SaveFileDialog sfd = new SaveFileDialog();
            sfd.Filter = "jpeg图片|*.JPEG|gif图片|*.GIF|png图片|*.PNG";//设置文件类型
            sfd.FileName = "temp";//设置默认文件名
            sfd.AddExtension = true;//设置自动在文件名中添加扩展名
            if (sfd.ShowDialog() == DialogResult.OK)
            {
                Bitmap bmp = new Bitmap(pictureBox1.Image);
                ImageFormat imageformat = null;
                switch (sfd.FilterIndex)
                {
                    case 1:
                        imageformat = System.Drawing.Imaging.ImageFormat.Jpeg;
                        break;
                    case 2:
                        imageformat = System.Drawing.Imaging.ImageFormat.Gif;
                        break;
                    case 3:
                        imageformat = System.Drawing.Imaging.ImageFormat.Png;
                        break;
                }

                Graphics g = Graphics.FromImage(bmp);
                //画图
                foreach (var item in ltPoly)
                {
                    draw_paint.DrawPolygon(line_color, item.ToArray());
                }
                bmp.Save(sfd.FileName, imageformat);
                bmp.Dispose();
                g.Dispose();
                MessageBox.Show("保存成功！", "注意", MessageBoxButtons.OK, MessageBoxIcon.Information);
                //打开文件
                System.Diagnostics.Process.Start(sfd.FileName.ToString());
                //打开文件夹
                //System.Diagnostics.Process.Start(localFilePath.Substring(0, localFilePath.LastIndexOf("\\")));
            }
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            comboBox1.SelectedIndex = 0;
            action_type = "矩形";
        }

        private void pictureBox1_MouseDown(object sender, MouseEventArgs e)
        {
            if (pictureBox1.Image == null)
            {
                MessageBox.Show("请先选择图片");
                return;
            }

            if (action_type.IndexOf("矩形") >= 0)
            {
                if (e.Button == MouseButtons.Left)
                {
                    start = e.Location;
                    need_draw_tmp = true;
                }
            }
            else if (action_type.IndexOf("四边形") >= 0)
            {
                Graphics g = pictureBox1.CreateGraphics();
                //绘制多边形  low版本
                if (is_first_down)  //首先第一次创建两个点如下(e.X, e.Y），（ e.X + 1, e.Y + 1)
                {
                    //first point down
                    if (e.Button == MouseButtons.Left)
                    {
                        is_first_down = false;
                        if (polyPoints == null) polyPoints = new List<Point>();
                        polyPoints.Add(e.Location);
                        need_draw_tmp = true;
                    }
                }
                else
                {
                    //add new point
                    if (e.Button == MouseButtons.Left)
                    {
                        //添加新的点
                        Point point = new Point(e.X, e.Y);
                        polyPoints.Add(point);

                        if (polyPoints.Count > 0 && polyPoints.Count % 4 == 0)
                        {
                            //转化坐标
                            Point temp;
                            List<Point> ltTempPoints = new List<Point>();
                            foreach (var item in polyPoints)
                            {
                                GetImagePixLocation(pictureBox1, item, out temp);
                                ltTempPoints.Add(temp);
                            }
                            polyPoints = ltTempPoints;
                            ltPoly.Add(polyPoints);
                            DrawPloy(true);
                        }
                    }
                }
            }
            end = e.Location;
            pictureBox1.Invalidate();
        }

        private void pictureBox1_MouseMove(object sender, MouseEventArgs e)
        {

            if (action_type.IndexOf("矩形") >= 0)
            {
                //绘制矩形框 并填充
                if (need_draw_tmp)
                {
                    if (e.Button != MouseButtons.Left) return;
                    end = e.Location;
                    pictureBox1.Invalidate();
                }
            }
            else if (action_type.IndexOf("四边形") >= 0)
            {
                //绘制多边形
                if (need_draw_tmp)
                {
                    //if (e.Button != MouseButtons.Left) return;
                    end = e.Location;
                    pictureBox1.Invalidate();//此代码不可省略
                    //Graphics g = pictureBox1.CreateGraphics();
                    //抗锯齿

                }
            }
        }

        private void pictureBox1_MouseUp(object sender, MouseEventArgs e)
        {
            if (action_type.IndexOf("矩形") >= 0)
            {
                //绘制矩形框 
                if (e.Button == MouseButtons.Left)
                {
                    end = e.Location;
                    need_draw_tmp = false;
                }

                Graphics g = pictureBox1.CreateGraphics();
                Point temp_start;
                Point temp_end;
                GetImagePixLocation(pictureBox1, start, out temp_start);
                GetImagePixLocation(pictureBox1, end, out temp_end);
                Rectangle temp_rect = new Rectangle(Math.Min(temp_start.X, temp_end.X),
                    Math.Min(temp_start.Y, temp_end.Y),
                    Math.Abs(temp_start.X - temp_end.X),
                    Math.Abs(temp_start.Y - temp_end.Y));

                draw_paint.DrawRectangle(line_color, temp_rect);//画矩形
                //TODO：  扩充点 可弹出选择框选择标注类型
                Point[] tempPoints = new Point[4];
                tempPoints[0] = new Point(Math.Min(temp_start.X, temp_end.X), Math.Min(temp_start.Y, temp_end.Y));
                tempPoints[2] = new Point(Math.Max(temp_start.X, temp_end.X), Math.Max(temp_start.Y, temp_end.Y));
                tempPoints[1] = new Point(tempPoints[2].X, tempPoints[0].Y);
                tempPoints[3] = new Point(tempPoints[0].X, tempPoints[2].Y);
                ltPoly.Add(tempPoints.ToList());
                pictureBox1.Image = GetMergeBitmap();
                g.Dispose();
            }

        }

        private void pictureBox1_Paint(object sender, PaintEventArgs e)
        {
            PictureBox pic = sender as PictureBox;
            if (action_type.IndexOf("矩形") >= 0)
            {
                //绘制矩形框 并填充
                Pen pen = new Pen(Color.Red, 3);
                pen.DashStyle = System.Drawing.Drawing2D.DashStyle.Dot;     //绘制线的格式
                //绘制矩形框 并填充
                if (need_draw_tmp)
                {
                    //此处是为了在绘制时可以由上向下绘制，也可以由下向上
                    rectA = new Rectangle(Math.Min(start.X, end.X), Math.Min(start.Y, end.Y), Math.Abs(start.X - end.X), Math.Abs(start.Y - end.Y));
                    e.Graphics.DrawRectangle(pen, rectA);



                }
                pen.Dispose();
            }
            else if (action_type.IndexOf("四边形") >= 0)
            {
                //多边形
                if (polyPoints != null)
                {
                    if (need_draw_tmp)
                    {
                        //抗锯齿
                        e.Graphics.SmoothingMode = SmoothingMode.AntiAlias;
                        e.Graphics.DrawLine(pen_yellow, polyPoints.First(), end);
                        e.Graphics.DrawLine(pen_red, polyPoints.Last(), end);

                        if (polyPoints.Count > 1)
                        {
                            for (int i = 0; i < polyPoints.Count - 1; i++)
                            {
                                e.Graphics.DrawLine(pen_red, polyPoints[i], polyPoints[i + 1]);
                            }
                        }
                    }
                }
            }

        }

        private Bitmap GetMergeBitmap()
        {
            Bitmap tmp_bmp = (Bitmap)bg_image.Clone();
            merge_paint = Graphics.FromImage(tmp_bmp);
            merge_paint.DrawImage(tmp_bitmap, 0, 0);//将中间画布绘制的内容绘制到原始画布上
            merge_paint.Dispose();
            return tmp_bmp;
        }

        private void GetImagePixLocation(PictureBox pictureBox, System.Drawing.Point pictureBoxPoint, out System.Drawing.Point imagePoint)
        {
            imagePoint = new System.Drawing.Point(0, 0);
            System.Drawing.Size imageSize = pictureBox.Image.Size;
            double scale;
            int detalInHeight = 0;
            int detalInWidth = 0;
            if (Convert.ToDouble(pictureBox.Size.Width) / pictureBox.Size.Height > Convert.ToDouble(imageSize.Width) / imageSize.Height)
            {
                scale = 1.0 * imageSize.Height / pictureBox.Size.Height;
                detalInWidth = Convert.ToInt32((pictureBox.Size.Width * scale - imageSize.Width) / 2.0);
            }
            else
            {
                scale = 1.0 * imageSize.Width / pictureBox.Size.Width;
                detalInHeight = Convert.ToInt32((pictureBox.Size.Height * scale - imageSize.Height) / 2.0);
            }
            imagePoint.X = Convert.ToInt32(pictureBoxPoint.X * scale - detalInWidth);
            imagePoint.Y = Convert.ToInt32(pictureBoxPoint.Y * scale - detalInHeight);
        }

        private void DrawPloy(bool fill = true)
        {
            //绘制矩形框 并填充
            draw_paint.SmoothingMode = SmoothingMode.HighQuality;//抗锯齿
            draw_paint.DrawPolygon(line_color, polyPoints.ToArray());
            //填充多边形
            if (fill)
            {
                draw_paint.FillPolygon(fill_brush, polyPoints.ToArray());
            }
            //TODO：  扩充点 可弹出选择框选择标注类型
            pictureBox1.Image = GetMergeBitmap();
            is_first_down = true;
            need_draw_tmp = false;
            polyPoints = null;
        }

        private void comboBox1_SelectedIndexChanged(object sender, EventArgs e)
        {
            action_type = comboBox1.Text;
        }

        private void button3_Click(object sender, EventArgs e)
        {
            if (ltPoly.Count == 0)
            {
                return;
            }
            string file = "lable.txt";
            FileStream fs = new FileStream(file, FileMode.Create);
            StreamWriter sw = new StreamWriter(fs, Encoding.UTF8);
            foreach (var item in ltPoly)
            {
                sw.WriteLine(string.Format("({0},{1}),({2},{3}),({4},{5}),({6},{7})",
                    item[0].X, item[0].Y,
                    item[1].X, item[1].Y,
                    item[2].X, item[2].Y,
                    item[3].X, item[3].Y
                    ));
            }
            sw.Close();
            fs.Close();
            MessageBox.Show("保存成功！", "注意", MessageBoxButtons.OK, MessageBoxIcon.Information);
            //打开文件
            System.Diagnostics.Process.Start(file);
        }
    }
}

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