how to decompose integer array to a byte array (pixel codings)

Hi sorry for being annoying by rephrasing my question but I am just on the point of discovering my answer.

I have an array of int composed of RGB values, I need to decompose that int array into a byte array, but it should be in BGR order.

The array of int composed of RGB values is being created like so:

pix[index++] = (255 << 24) | (red << 16) | blue;

From stackoverflow

• #define N something
  unsigned char bytes[N*3];
  unsigned int  ints[N];
  
  for(int i=0; i<N; i++) {
      bytes[i*3]   = ints[i];       // Blue
      bytes[i*3+1] = ints[i] >> 8;  // Green
      bytes[i*3+2] = ints[i] >> 16; // Red
  }
  

  Jay Bazuzi : Wrong langauge; magic numbers are evil

  Can Berk Güder : The question doesn't state a specific language, and I only saw the c# tag now.

• r = (pix[index] >> 16) & 0xFF

  the rest is similar, just change 16 to 8 or 24.

  Can Berk Güder : & 0xFF is not really necessary if r is a char.

• C# code

  
          // convert integer array representing [argb] values to byte array representing [bgr] values
          private byte[] convertArray(int[] array)
          {
              byte[] newarray = new byte[array.Length * 3];
  
              for (int i = 0; i < array.Length; i++)
              {
  
                  newarray[i * 3] = (byte)array[i];
                  newarray[i * 3 + 1] = (byte)(array[i] >> 8);
                  newarray[i * 3 + 2] = (byte)(array[i] >> 16);
  
              }
              return newarray;
          }
  

• Using Linq:

          pix.SelectMany(i => new byte[] { 
              (byte)(i >> 0),
              (byte)(i >> 8),
              (byte)(i >> 16),
          }).ToArray();
  

  Or

          return (from i in pix
                  from x in new[] { 0, 8, 16 }
                  select (byte)(i >> x)
                 ).ToArray();