anchor.diff:  
         2: // LZW compression
         begin
  +        {$IFDEF LZW_DEBUG}
  +        writeln('LZW compressed image type');
  +        {$ENDIF}
           LZWDecompressBlock( Block._Data,
                               Block._Size,
                               BitmapOutputPointer,
  
positive.code:   ptr: PByte;
    i: integer;
    img: TfpgImage;
  begin
    BitmapOutputPointer := nil;
    BitmapData := nil;
    ptr := nil;
  
    // Allocate memory to store the bitmap
    BitmapData := GetMem( TotalSize );
  
negative.code:     case Block._CompressionType of
        0,1: // uncompressed (I'm not sure about 1)
        begin
          {$IFDEF LZW_DEBUG}
          writeln('Uncompressed image type');
          {$ENDIF}
          MemCopy( Block._Data^, BitmapOutputPointer^, Block._Size );
          BytesWrittenFromBlock := Block._Size;
          inc( BytesWritten, BytesWrittenFromBlock );
  