使用GDI+制作反色图片

近来研究了一下GDI+绘图的基本操作，也学到了不少东西

绘制灰色图片：

System.Drawing.Bitmap bm = new System.Drawing.Bitmap

(this.pictureBox1.Image.Width,

this.pictureBox1.Image.Height,

System.Drawing.Imaging.PixelFormat.Format24bppRgb);

System.Drawing.Bitmap bmOriginal = (Bitmap)this.pictureBox1.Image;

for(int y=0;y<bmOriginal.Height;y++)

{

for(int x=0;x<bmOriginal.Width;x++)

{

Color c=bmOriginal.GetPixel(x,y);

int red,green,blue;

red = (int)(c.R*0.3 + c.G*0.59+ c.B*0.11);

green = (int)(c.R*0.3 + c.G*0.59+ c.B*0.11);

blue = (int)(c.R*0.3 + c.G*0.59+ c.B*0.11);

bm.SetPixel(x,y,Color.FromArgb(red,green,blue));

}

}

this.pictureBox1.Image = bm;

绘制反色图片：

System.Drawing.Bitmap bm = new System.Drawing.Bitmap

(this.pictureBox1.Image.Width,

this.pictureBox1.Image.Height,

System.Drawing.Imaging.PixelFormat.Format24bppRgb);

System.Drawing.Bitmap bmOriginal = (Bitmap)this.pictureBox1.Image;

for(int y=0;y<bmOriginal.Height;y++)

{

for(int x=0;x<bmOriginal.Width;x++)

{

Color c=bmOriginal.GetPixel(x,y);

int red,green,blue;

red = (int)(255-c.R);

green = (int)(255-c.G);

blue = (int)(255-c.B);
}

bm.SetPixel(x,y,Color.FromArgb(red,green,blue));

}

this.pictureBox1.Image = bm;

在使用Graphics的DrawImage方法时，graphics使用Graphics.FromImage(Image)获得，既可绘制Image.

还有许多技巧，具体参考：http://www.bobpowell.net/faqmain.htm和codeproject上的一些文章和代码