No 71 · 以馬賽克效果顯示圖像

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

namespace Ex13_15
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        private System.Drawing.Bitmap MyBitmap;
        private void button2_Click(object sender, EventArgs e)
        {
            //打開圖像文件
            OpenFileDialog openFileDialog = new OpenFileDialog();
            openFileDialog.Filter = "圖像文件(JPeg, Gif, Bmp, etc.)|*.jpg;*.jpeg;*.gif;*.bmp;*.tif; *.tiff; *.png| JPeg 圖像文件(*.jpg;*.jpeg)|*.jpg;*.jpeg |GIF 圖像文件(*.gif)|*.gif |BMP圖像文件(*.bmp)|*.bmp|Tiff圖像文件(*.tif;*.tiff)|*.tif;*.tiff|Png圖像文件(*.png)| *.png |所有文件(*.*)|*.*";
            if (openFileDialog.ShowDialog() == DialogResult.OK)
            {
                //得到原始大小的圖像
                Bitmap SrcBitmap = new Bitmap(openFileDialog.FileName);
                //得到縮放後的圖像
                MyBitmap = new Bitmap(SrcBitmap, this.pictureBox1.Width, this.pictureBox1.Height);
                this.pictureBox1.Image = MyBitmap;
            }
        }

        private void button1_Click(object sender, EventArgs e)
        {
            //以馬賽克效果顯示圖像
            try
            {
                int dw = MyBitmap.Width / 50;
                int dh = MyBitmap.Height / 50;
                Graphics g = this.pictureBox1.CreateGraphics();
                g.Clear(Color.Gray);
                Point[] MyPoint = new Point[2500];
                for (int x = 0; x < 50; x++)
                    for (int y = 0; y < 50; y++)
                    {
                        MyPoint[x * 50 + y].X = x * dw;
                        MyPoint[x * 50 + y].Y = y * dh;
                    }
                Bitmap bitmap = new Bitmap(MyBitmap.Width, MyBitmap.Height);
                for (int i = 0; i < 10000; i++)
                {
                    System.Random MyRandom = new Random();
                    int iPos = MyRandom.Next(2500);
                    for (int m = 0; m < dw; m++)
                        for (int n = 0; n < dh; n++)
                        {
                            bitmap.SetPixel(MyPoint[iPos].X + m, MyPoint[iPos].Y + n, MyBitmap.GetPixel(MyPoint[iPos].X + m, MyPoint[iPos].Y + n));
                        }
                    this.pictureBox1.Refresh();
                    this.pictureBox1.Image = bitmap;
                }
                for (int i = 0; i < 2500; i++)
                    for (int m = 0; m < dw; m++)
                        for (int n = 0; n < dh; n++)
                        {
                            bitmap.SetPixel(MyPoint[i].X + m, MyPoint[i].Y + n, MyBitmap.GetPixel(MyPoint[i].X + m, MyPoint[i].Y + n));
                        }
                this.pictureBox1.Refresh();
                this.pictureBox1.Image = bitmap;
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message, "信息提示");
            }
        }

        private void button3_Click(object sender, EventArgs e)
        {
            //以馬賽克效果隱藏圖像
            try
            {
                MyBitmap = (Bitmap)this.pictureBox1.Image.Clone();
                int dw = MyBitmap.Width / 50;
                int dh = MyBitmap.Height / 50;
                Graphics g = this.pictureBox1.CreateGraphics();
                Point[] MyPoint = new Point[2500];
                for (int x = 0; x < 50; x++)
                    for (int y = 0; y < 50; y++)
                    {
                        MyPoint[x * 50 + y].X = x * dw;
                        MyPoint[x * 50 + y].Y = y * dh;
                    }
                Bitmap bitmap = new Bitmap(MyBitmap.Width, MyBitmap.Height);
                for (int i = 0; i < 2500; i++)
                    for (int m = 0; m < dw; m++)
                        for (int n = 0; n < dh; n++)
                        {
                            bitmap.SetPixel(MyPoint[i].X + m, MyPoint[i].Y + n, MyBitmap.GetPixel(MyPoint[i].X + m, MyPoint[i].Y + n));
                        }
                this.pictureBox1.Refresh();
                this.pictureBox1.Image = bitmap;
                bitmap = (Bitmap)this.pictureBox1.Image.Clone();
                for (int i = 0; i < 10000; i++)
                {
                    System.Random MyRandom = new Random();
                    int iPos = MyRandom.Next(2500);
                    for (int m = 0; m < dw; m++)
                        for (int n = 0; n < dh; n++)
                        {
                            bitmap.SetPixel(MyPoint[iPos].X + m, MyPoint[iPos].Y + n, this.pictureBox1.BackColor);
                        }
                    this.pictureBox1.Refresh();
                    this.pictureBox1.Image = bitmap;
                }
                for (int i = 0; i < 2500; i++)
                    for (int m = 0; m < dw; m++)
                        for (int n = 0; n < dh; n++)
                        {
                            bitmap.SetPixel(MyPoint[i].X + m, MyPoint[i].Y + n, this.pictureBox1.BackColor);
                        }
                g.Clear(this.pictureBox1.BackColor);
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message, "信息提示");
            }
        }
    }
}