//
//  file name: coeff.h
//  written by Ee-Chien Chang
//----------------------------------------------------
//         T A B L E 
//----------------------------------------------------
//
//   a nos_row by nos_col table of   pointers.
//   Each pointer points to an  BLOCK_SIZE by BLOCK_SIZE array.
//   Each entry of the array is a 3-byte coeff.
//
//   The content of the array is stored in file: an array
//        correspoind to a single file.
//   
//   when an entry of the table is zero, this mean that
//      the file is not yet loaded into memory.
//      To load it into memory, use   
//           loadimage (i,j)
//----------------------------------------------------

#ifndef COEFF_H
#define COEFF_H
class table
{
   public:
                      ~table     ();
                       table     ( int row, int col );
               void    loadimage ( char * name, int i,int j);
               unsigned char ** tb;
   private:
               int     nos_row;
               int     nos_col;
};

//-----------------------------------------------------
//    F O U R      T A B L E
//-----------------------------------------------------
//  this are just 3 copies of table correspponding to
//   d (diagonal), v (vertical ), h( horizontal ), and m (mixed)
//
//  For simplicity we try not to use the C++
//              inhereditance or subclass or....
//-----------------------------------------------------
//
//   request ( stream, row,  start_from, end_at ):
//             copy value from  (row, start_from) to (row, end_at)
//             to   stream.
//
//   The format of output to stream is...
//
//    a pixel of mixed, followed by a pixel of h, v, d.
//    each pixel is 3 bytes consisting red, green, blue.
//    That is...
//
//      m_r  m_g  m_b  v_r v_g v_b  h_r h_g h_b   d_r d_g d_b
//-----------------------------------------------------
//
//  As it is not yet clear whether the above format is better
//  or a seperate stream for each d,v,h,n,m or
//  even seperate stream for red, green, blue is better.
//  We will not implement other options.
//
//-----------------------------------------------------

class four_table
{
  public:
           four_table ( int level, int nos_row, int nos_col, char *basename );
          ~four_table();

     int   request    ( unsigned char *stream, int gap, int row, int st, int en );

     table *v;
     table *d;
     table *h;
     table *m;

  private:
     void   loadimage ( int i, int j );
     char * mybasename;
     int    nos_row;
     int    nos_col;
     int    mylevel;
};

//--------------------------------------------------------
//    C  O  E  F
//--------------------------------------------------------
//   
//  keeping the coefficient  (in memory and fiiles)
//  Basically  using  the class  four_table.
//
//  However, contain overall image information like total
//  number of level, width, height, etc...
//--------------------------------------------------------
//
// NOTE
//    request  ( , ,reqlist)    will destruct the linked list reqlist
//                              after the call.
//
//--------------------------------------------------------   

class coeff
{

  public:
                  coeff ( char *base_name );
                  coeff () { nos_level =0;}
                 ~coeff();

//   int         request (unsigned char * mystream, int level, int st_row, int en_row,
//                                                   int st_col, int en_col );

     int         request (unsigned char * mystream, int gap,
                                                    int level, int row,  item* reqlist);
     void        getaverage ( unsigned char **);

     int         Nos_Level ()   {return nos_level;}
     int         Block_Size()   {return BLOCK_SIZE;}

  private:
     four_table **table_list       ;     //

     //------------ h e a d e r    f i l e    i n f o   --------------

     int          nos_level        ;
     int          image_width      ;     // equivalent to number of column 
     int          image_height     ;     // number of row
     void         read_file_header ();   //
     char        *basename;
};

#endif