插入圖像，灰度和擦拭

Question

我在C＃ 被開發Windows應用程序，在C＃轉換這個程序有三個按鈕（打開，保存，灰度） 並具有圖片框在應用

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 MyFirstWindowsApplication 
{ 
    public partial class Form1 : Form 
    { 
     Bitmap newbitmap; 
     Bitmap newbitmap2; 
     Bitmap outp; 
     Image file; 
     public Form1() 
     { 
      InitializeComponent(); 
     } 

     private void button1_Click(object sender, EventArgs e) 
     { 
      DialogResult dr = openFileDialog1.ShowDialog(); 

      if (dr == DialogResult.OK) 
      { 
       file = Image.FromFile(openFileDialog1.FileName); 
       newbitmap = new Bitmap(openFileDialog1.FileName); 
       newbitmap2 = new Bitmap(openFileDialog1.FileName); 
       outp = new Bitmap(openFileDialog1.FileName); 
       pictureBox1.Image = file; 
      } 
     } 


     private void button2_Click(object sender, EventArgs e) 
     { 
      DialogResult dr = saveFileDialog1.ShowDialog(); 
      if (dr == DialogResult.OK) 
      { 
       if (newbitmap != null) 
       { 
        if (saveFileDialog1.FileName.Substring(saveFileDialog1.FileName.Length - 3).ToLower() == "bmp") 
        { 
         newbitmap.Save(saveFileDialog1.FileName, ImageFormat.Bmp); 
        } 

        if (saveFileDialog1.FileName.Substring(saveFileDialog1.FileName.Length - 3).ToLower() == "jpg") 
        { 
         newbitmap.Save(saveFileDialog1.FileName, ImageFormat.Bmp); 
        } 

        if (saveFileDialog1.FileName.Substring(saveFileDialog1.FileName.Length - 3).ToLower() == "bmp") 
        { 
         newbitmap.Save(saveFileDialog1.FileName, ImageFormat.Jpeg); 
        } 

        if (saveFileDialog1.FileName.Substring(saveFileDialog1.FileName.Length - 4).ToLower() == "jpeg") 
        { 
         newbitmap.Save(saveFileDialog1.FileName, ImageFormat.Jpeg); 
        } 

        if (saveFileDialog1.FileName.Substring(saveFileDialog1.FileName.Length - 3).ToLower() == "png") 
        { 
         newbitmap.Save(saveFileDialog1.FileName, ImageFormat.Png); 
        } 

        if (saveFileDialog1.FileName.Substring(saveFileDialog1.FileName.Length - 3).ToLower() == "gif") 
        { 
         newbitmap.Save(saveFileDialog1.FileName, ImageFormat.Gif); 
        } 
       } 
       else 
       { 
        MessageBox.Show("you need to open file first"); 
       } 
      } 
     } 

     private void button3_Click(object sender, EventArgs e) 
     { 


      for (int x = 0; x < newbitmap.Width; x++) 
      { 
       for (int y = 0; y < newbitmap.Height; y++) 
       { 
        Color originalColor = newbitmap.GetPixel(x, y); 
        int grayscale = (int)((originalColor.R * .3) + (originalColor.G * .59) + (originalColor.B * .11)); 
        Color newColor = Color.FromArgb(grayscale, grayscale, grayscale); 
        newbitmap.SetPixel(x, y, newColor); 
       } 

      } 

      int tmax = 10; 
      int xmax=newbitmap.Width; 
      int ymax=newbitmap.Height; 
      for (int t = 0; t <= tmax; t += 1) 
      { 

       for (int x = 0; x < xmax; x++) 
       { 
        for (int y = 0; y < ymax; y++) 
        { 
         if ((x/xmax) > (t/tmax)) 
         { 
          Color originalco = newbitmap2.GetPixel(x, y); 
          outp.SetPixel(x, y, originalco); 
         } 
         else 
         { 
          Color originalco3 = newbitmap.GetPixel(x, y); ; 
          outp.SetPixel(x, y, originalco3); 
         } 
         pictureBox1.Image = outp; 
        } 


       } 
      } 



     } 
    } 
} 

顯示圖片

問題是犯規使擦拭過渡

Answer 1

要進行灰度化圖像考慮使用這個更好的解決方案

public Image MakeGrayscale(Image original) 
{ 
    Image newBitmap = new Bitmap(original.Width, original.Height); 
    Graphics g = Graphics.FromImage(newBitmap); 
    ColorMatrix colorMatrix = new ColorMatrix(
     new float[][] 
     { 
      new float[] {0.299f, 0.299f, 0.299f, 0, 0}, 
      new float[] {0.587f, 0.587f, 0.587f, 0, 0}, 
      new float[] {.114f, .114f, .114f, 0, 0}, 
      new float[] {0, 0, 0, 1, 0}, 
      new float[] {0, 0, 0, 0, 1} 
     }); 

    ImageAttributes attributes = new ImageAttributes(); 
    attributes.SetColorMatrix(colorMatrix); 
    g.DrawImage(original, new Rectangle(0, 0, original.Width, original.Height), 
     0, 0, original.Width, original.Height, GraphicsUnit.Pixel, attributes); 

    g.Dispose(); 
    return newBitmap; 
} 

然後

pictureBox1.Image = MakeGrayscale(newbitmap); 

即使在保存程序中也有一些錯誤。試試這個：

private void button2_Click(object sender, EventArgs e) 
{ 
    if (newbitmap == null) 
    { 
     MessageBox.Show("you need to open file first"); 
     return; 
    } 

    if (DialogResult dr = saveFileDialog1.ShowDialog() == DialogResult.OK) 
    { 
     string ext = Path.GetExtension(saveFileDialog1.FileName).ToLower(); 
     switch (ext) 
     { 
      case ".bmp": 
       newbitmap.Save(saveFileDialog1.FileName, ImageFormat.Bmp); 
       break; 
      case ".jpg": 
      case ".jpeg": 
       newbitmap.Save(saveFileDialog1.FileName, ImageFormat.Jpeg); 
       break; 
      case ".png": 
       newbitmap.Save(saveFileDialog1.FileName, ImageFormat.Png); 
       break; 
      case ".gif": 
       newbitmap.Save(saveFileDialog1.FileName, ImageFormat.Gif); 
       break; 
      default: MessageBox.Show("Extension not supported"); 
     } 
    } 
} 

在我看來過渡爲此不起作用：你的主線程（GUI一個理解）快速變化（非常快）PictureBox的圖像在一個循環，但同時在這個循環中它沒有有時間更新圖形用戶界面，所以picturebox被有效地改變，只有退出循環..所以你沒有看到過渡。
您應該使用BackgroundWorker更改picturebox圖像（在每個循環之間暫停，以便讓人眼看到新圖像）。