anchor.diff:                  let v = uint16 (off + v)
                   let huff = coder.dcLumInv.[dc]
                   x.Write(huff)
  -                x.Write(Codeword(byte dc, v))
  +                x.Write(Codeword.Create(dc, v))
   
               member x.WriteACLum(leadingZeros : int, v : int) =
                   assert(leadingZeros < 16) 
  
positive.code:                 let index = (byte leadingZeros <<< 4) ||| byte dc
                  let huff = coder.acChromaInv.[int index]
                  x.Write huff
                  x.Write(Codeword(byte dc, v))
  
          let writeBlock (bs : BitStream) (block : V3i[]) =
  
  
negative.code: 
  
          type BitStream(coder : HuffmanCoder, s : System.IO.Stream) =
              let mutable current = Codeword.Empty
              let result = System.Collections.Generic.List<byte>()
  
              static let bla (f : byte[]) =
  