DotNet Bitmap Creation Optimization

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    ...
    Bitmap bmp = new Bitmap(width, height);

    for (int x = 0; x < width; x++)
        for (int y = 0; y < height; y++)
            bmp.SetPixel(x, y, myColors[(int)(256 * fractal.Grid[x, y])]);
    ...

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   ...
   Bitmap bmp = new Bitmap(width, height);        
   
   //Create a new instance of BitmapData from the bitmap using LockBits method
   //This gives us read and write access pixel-by-pixel in unsafe mode
   BitmapData bmpData = bmp.LockBits(new Rectangle(0, 0, bmp.Width, bmp.Height), ImageLockMode.ReadWrite, bmp.PixelFormat);

   //Get a pointer to the first pixel of the bitmap 
   IntPtr ptr = bmpData.Scan0;

   //Use unsafe code to move through the pixels of the bitmap and set each pixel's color 

   unsafe
   {
       //Get a pointer to the first pixel of the bitmap as bytes 
       byte* p = (byte*)ptr.ToPointer();

       //Loop through the pixels in parallel (splitting up work among multiple threads)
       Parallel.For(0, bmpData.Stride * (bmpData.Height) / 4, i =>
       {
           //Calculate the x and y pixel positions based on the index value
           int x = i % width;
           int y = i / width;

           //Get the color index for this pixel from the plasma instance and use it to get the corresponding color from the myColors array
           int index = (int)(256 * plasma.Grid[x, y]);
           Color c = myColors[index];

           //Set the color values for the current pixel in the byte array
           p[i * 4] = c.B;
           p[i * 4 + 1] = c.G;
           p[i * 4 + 2] = c.R;
           p[i * 4 + 3] = c.A;
       });
   }

   //Unlock the bitmap data
   bmp.UnlockBits(bmpData);
   ...