かわいらしいにゃんこの画像をリソースに登録しておいて、あえて緑色に染めて描画する例。
private void Form1_Paint(object sender, PaintEventArgs e) { using (Bitmap bmp = Resources.Cat) { BitmapData bd = bmp.LockBits( new Rectangle(0, 0, bmp.Width, bmp.Height), ImageLockMode.ReadWrite, bmp.PixelFormat); Console.WriteLine(bmp.PixelFormat); IntPtr scan0 = bd.Scan0; byte[] buff = new byte[bd.Height * bd.Width * 3]; Marshal.Copy(scan0, buff, 0, buff.Length); for (int y = 0; y < bd.Height; y++) { for (int x = 0; x < bd.Width; x++) { int index = y * bd.Width * 3 + x * 3; buff[index] = 0; buff[index + 1] = 255; buff[index + 2] = 0; } } Marshal.Copy(buff, 0, scan0, buff.Length); bmp.UnlockBits(bd); e.Graphics.DrawImage(bmp, 0, 0, Width, Height); } }