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;



namespace B87874403

{

    public partial class Form1 : Form

    {

        public Form1()

        {

            InitializeComponent();

        }



        private void button1_Click(object sender, EventArgs e)

        {

            OpenFileDialog dlg = new OpenFileDialog();

            if (dlg.ShowDialog() == DialogResult.OK)

            {

                label1.Text = dlg.FileName;

            }

        }



        private void button2_Click(object sender, EventArgs e)

        {

            DownloadDialog dlg = new DownloadDialog();

            if (dlg.ShowDialog() == DialogResult.OK)

            {

                label1.Text = dlg.FileName;

            }

        }



        private void button4_Click(object sender, EventArgs e)

        {

            if (label1.Text == "")

            {

                MessageBox.Show("请先选择一个图片");

                return;

            }

            int span = (int)numericUpDown1.Value;

            Bitmap input = new Bitmap(label1.Text);

            Bitmap output = new Bitmap(input.Width, input.Height);

            var g = Graphics.FromImage(output);

            g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;

            g.FillRectangle(Brushes.Black, new Rectangle(0, 0, input.Width, input.Height));

            float dx = 0, dy = 0, dw = 0, dh = 0;

            Color brushcolor = Color.White;

            for (int i = 0; i < input.Width / span; i++)

            {

                for (int j = 0; j < input.Height / span; j++)

                {

                    float avgcolor = 0;

                    for (int k = i * span; k < i * span + span; k++)

                    {

                        for (int l = j * span; l < j * span + span; l++)

                        { 

                            Color c = input.GetPixel(k,l);

                            avgcolor += c.GetBrightness();

                        }

                    }

                    avgcolor /= (span * span);

                    dx = (1 - avgcolor) / 2 * span;

                    dy = dx;

                    dw = avgcolor * span;

                    dh = dw;

                    g.FillEllipse(new SolidBrush(brushcolor), i * span + dx, j * span + dy, dw, dh);

                }

            }

            pictureBox1.Image = output;

        }



        private void btnSave_Click(object sender, EventArgs e)

        {

            SaveFileDialog sfd = new SaveFileDialog();

            sfd.Filter = "bitmap|*.bmp";

            if (sfd.ShowDialog() == System.Windows.Forms.DialogResult.OK)

            {

                Image img = pictureBox1.Image;

                img.Save(sfd.FileName, ImageFormat.Bmp);

            }

        }



        private void btnExit_Click(object sender, EventArgs e)

        {

            Application.Exit();

        }

    }

}

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.Net;

using System.Text.RegularExpressions;

using System.Reflection;

using System.IO;



namespace B87874403

{

    public partial class DownloadDialog : Form

    {

        public DownloadDialog()

        {

            InitializeComponent();

        }



        public string FileName { get; set; }



        private void textBox1_TextChanged(object sender, EventArgs e)

        {

            try

            {

                pictureBox1.ImageLocation = textBox1.Text;

            }

            catch { }

        }



        private void button1_Click(object sender, EventArgs e)

        {

            WebClient wc = new WebClient();

            FileName = "";

            try

            {

                string fn = RndName(textBox1.Text);

                wc.DownloadFile(textBox1.Text, fn);

                FileName = fn;

            }

            catch {

                MessageBox.Show("无法下载图片，请重新选择");

            }

        }



        private string RndName(string url)

        {

            Uri u = new Uri(url);

            string fn = u.GetLeftPart(UriPartial.Path);

            string pattern = @"\.\w+$";

            string rnd =  Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location) + "\\" + new TimeSpan(DateTime.Now.Ticks - new DateTime(1970, 1, 1).Ticks).TotalSeconds.ToString();

            if (Regex.IsMatch(fn, pattern))

                fn = rnd + Regex.Match(fn, pattern).Value;

            else

                fn = rnd + ".jpg";

            return fn;

        }

    }



}

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;



namespace B87874403

{

    public partial class Form1 : Form

    {

        public Form1()

        {

            InitializeComponent();

        }



        private void button1_Click(object sender, EventArgs e)

        {

            OpenFileDialog dlg = new OpenFileDialog();

            if (dlg.ShowDialog() == DialogResult.OK)

            {

                label1.Text = dlg.FileName;

            }

        }



        private void button2_Click(object sender, EventArgs e)

        {

            DownloadDialog dlg = new DownloadDialog();

            if (dlg.ShowDialog() == DialogResult.OK)

            {

                label1.Text = dlg.FileName;

            }

        }



        private void button4_Click(object sender, EventArgs e)

        {

            if (label1.Text == "")

            {

                MessageBox.Show("请先选择一个图片");

                return;

            }

            int span = (int)numericUpDown1.Value;

            Bitmap input = new Bitmap(label1.Text);

            Bitmap output = new Bitmap(input.Width, input.Height);

            Bitmap bg = null;

            if (label4.Text != "")

            {

                bg = new Bitmap(input.Width / span, input.Height / span);

                var imgbg = new Bitmap(label4.Text);

                var bgg = Graphics.FromImage(bg);

                bgg.DrawImage(imgbg, 0, 0, input.Width / span, input.Height / span);

            }

            var g = Graphics.FromImage(output);

            g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;

            g.FillRectangle(Brushes.Black, new Rectangle(0, 0, input.Width, input.Height));

            float dx = 0, dy = 0, dw = 0, dh = 0;

            Color brushcolor = Color.White;

            for (int i = 0; i < input.Width / span; i++)

            {

                for (int j = 0; j < input.Height / span; j++)

                {

                    float avgcolor = 0;

                    for (int k = i * span; k < i * span + span; k++)

                    {

                        for (int l = j * span; l < j * span + span; l++)

                        { 

                            Color c = input.GetPixel(k,l);

                            avgcolor += c.GetBrightness();

                        }

                    }

                    avgcolor /= (span * span);

                    dx = (1 - avgcolor) / 2 * span;

                    dy = dx;

                    dw = avgcolor * span;

                    dh = dw;

                    if (bg != null)

                        brushcolor = bg.GetPixel(i, j);

                    g.FillEllipse(new SolidBrush(brushcolor), i * span + dx, j * span + dy, dw, dh);

                }

            }

            pictureBox1.Image = output;

        }



        private void btnSave_Click(object sender, EventArgs e)

        {

            SaveFileDialog sfd = new SaveFileDialog();

            sfd.Filter = "bitmap|*.bmp";

            if (sfd.ShowDialog() == System.Windows.Forms.DialogResult.OK)

            {

                Image img = pictureBox1.Image;

                img.Save(sfd.FileName, ImageFormat.Bmp);

            }

        }



        private void btnExit_Click(object sender, EventArgs e)

        {

            Application.Exit();

        }



        private void label4_Click(object sender, EventArgs e)

        {

            OpenFileDialog dlg = new OpenFileDialog();

            if (dlg.ShowDialog() == DialogResult.OK)

            {

                label4.Text = dlg.FileName;

            }

            else

            {

                label4.Text = "";

            }

        }

    }

}