transform8x8.c

JM 11.0 KTA 2.1 Source Code

/*!
 ***************************************************************************
 * \file transform8x8.c
 *
 * \brief
 *    8x8 transform functions
 *
 * \author
 *    Main contributors (see contributors.h for copyright, address and affiliation details) 
 *    - Yuri Vatis          <[e-mail]>
 *    - Jan Muenster        <[e-mail]>
 *
 * \date
 *    12. October 2003
 **************************************************************************
 */

#include <stdlib.h>
#include "transform8x8.h"



#define Q_BITS_8        16
#define DQ_BITS_8       6 
#define DQ_ROUND_8      (1<<(DQ_BITS_8-1))

#ifdef _NEW_8x8_ARRAYS_INCLUDED_
//! single scan pattern
const byte SNGL_SCAN8x8[64][2] = {
  {0,0}, {1,0}, {0,1}, {0,2}, {1,1}, {2,0}, {3,0}, {2,1}, {1,2}, {0,3}, {0,4}, {1,3}, {2,2}, {3,1}, {4,0}, {5,0},
  {4,1}, {3,2}, {2,3}, {1,4}, {0,5}, {0,6}, {1,5}, {2,4}, {3,3}, {4,2}, {5,1}, {6,0}, {7,0}, {6,1}, {5,2}, {4,3},
  {3,4}, {2,5}, {1,6}, {0,7}, {1,7}, {2,6}, {3,5}, {4,4}, {5,3}, {6,2}, {7,1}, {7,2}, {6,3}, {5,4}, {4,5}, {3,6},
  {2,7}, {3,7}, {4,6}, {5,5}, {6,4}, {7,3}, {7,4}, {6,5}, {5,6}, {4,7}, {5,7}, {6,6}, {7,5}, {7,6}, {6,7}, {7,7}
};

//! field scan pattern
const byte FIELD_SCAN8x8[64][2] = {
 {0,0}, {0,1}, {0,2}, {1,0}, {1,1}, {0,3}, {0,4}, {1,2}, {2,0}, {2,1}, {1,3}, {0,5}, {0,6}, {1,4}, {2,2}, {3,0},
 {3,1}, {2,3}, {1,5}, {0,7}, {1,6}, {2,4}, {3,2}, {4,0}, {4,1}, {3,3}, {2,5}, {1,7}, {2,6}, {3,4}, {4,2}, {5,0},
 {5,1}, {4,3}, {3,5}, {2,7}, {3,6}, {4,4}, {5,2}, {6,0}, {6,1}, {5,3}, {4,5}, {3,7}, {4,6}, {5,4}, {6,2}, {7,0},
 {7,1}, {6,3}, {5,5}, {4,7}, {5,6}, {6,4}, {7,2}, {7,3}, {6,5}, {5,7}, {6,6}, {7,4}, {7,5}, {6,7}, {7,6}, {7,7}
};


//! array used to find expencive coefficients
const byte COEFF_COST8x8[64] =
{
  3,3,3,3,2,2,2,2,2,2,2,2,1,1,1,1,
  1,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
};

#endif

// Notation for comments regarding prediction and predictors.
// The pels of the 4x4 block are labelled a..p. The predictor pels above
// are labelled A..H, from the left I..P, and from above left X, as follows:
//
//  Z  A  B  C  D  E  F  G  H  I  J  K  L  M   N  O  P  
//  Q  a1 b1 c1 d1 e1 f1 g1 h1
//  R  a2 b2 c2 d2 e2 f2 g2 h2
//  S  a3 b3 c3 d3 e3 f3 g3 h3
//  T  a4 b4 c4 d4 e4 f4 g4 h4
//  U  a5 b5 c5 d5 e5 f5 g5 h5
//  V  a6 b6 c6 d6 e6 f6 g6 h6
//  W  a7 b7 c7 d7 e7 f7 g7 h7
//  X  a8 b8 c8 d8 e8 f8 g8 h8


// Predictor array index definitions
#define P_Z (PredPel[0])
#define P_A (PredPel[1])
#define P_B (PredPel[2])
#define P_C (PredPel[3])
#define P_D (PredPel[4])
#define P_E (PredPel[5])
#define P_F (PredPel[6])
#define P_G (PredPel[7])
#define P_H (PredPel[8])
#define P_I (PredPel[9])
#define P_J (PredPel[10])
#define P_K (PredPel[11])
#define P_L (PredPel[12])
#define P_M (PredPel[13])
#define P_N (PredPel[14])
#define P_O (PredPel[15])
#define P_P (PredPel[16])
#define P_Q (PredPel[17])
#define P_R (PredPel[18])
#define P_S (PredPel[19])
#define P_T (PredPel[20])
#define P_U (PredPel[21])
#define P_V (PredPel[22])
#define P_W (PredPel[23])
#define P_X (PredPel[24])

/*!
 ************************************************************************
 * \brief
 *    Make intra 8x8 prediction according to all 9 prediction modes.
 *    The routine uses left and upper neighbouring points from
 *    previous coded blocks to do this (if available). Notice that
 *    inaccessible neighbouring points are signalled with a negative
 *    value in the predmode array .
 *
 *  \par Input:
 *     Starting point of current 8x8 block image posision
 *
 ************************************************************************
 */
int intrapred8x8( struct img_par *img,  //!< image parameters
                  int b8)

{
  int i,j;
  int s0;
  int PredPel[25];  // array of predictor pels
  imgpel **imgY = dec_picture->imgY;  // For MB level frame/field coding tools -- set default to imgY

  int mb_nr=img->current_mb_nr;

  PixelPos pix_a[8];
  PixelPos pix_b, pix_c, pix_d;

  int block_available_up;
  int block_available_left;
  int block_available_up_left;
  int block_available_up_right;
  int img_block_x = (img->mb_x)*4 + 2*(b8%2);
  int img_block_y = (img->mb_y)*4 + 2*(b8/2);
  int ioff = (b8%2)*8;
  int joff = (b8/2)*8;

  byte predmode = img->ipredmode[img_block_x][img_block_y];

  for (i=0;i<8;i++)
  {
    getNeighbour(mb_nr, ioff -1 , joff +i , 1, &pix_a[i]);
  }

  getNeighbour(mb_nr, ioff    , joff -1 , 1, &pix_b);
  getNeighbour(mb_nr, ioff +8 , joff -1 , 1, &pix_c);
  getNeighbour(mb_nr, ioff -1 , joff -1 , 1, &pix_d);
  
  pix_c.available = pix_c.available &&!(ioff == 8 && joff == 8);

  if (active_pps->constrained_intra_pred_flag)
  {
    for (i=0, block_available_left=1; i<8;i++)
      block_available_left  &= pix_a[i].available ? img->intra_block[pix_a[i].mb_addr]: 0;
    block_available_up       = pix_b.available ? img->intra_block [pix_b.mb_addr] : 0;
    block_available_up_right = pix_c.available ? img->intra_block [pix_c.mb_addr] : 0;
    block_available_up_left  = pix_d.available ? img->intra_block [pix_d.mb_addr] : 0;
  }
  else
  {
    block_available_left     = pix_a[0].available;
    block_available_up       = pix_b.available;
    block_available_up_right = pix_c.available;
    block_available_up_left  = pix_d.available;
  }

//  *left_available = block_available_left;
//  *up_available   = block_available_up;
//  *all_available  = block_available_up && block_available_left && block_available_up_left;

  // form predictor pels
  // form predictor pels
  if (block_available_up)
  {
    P_A = imgY[pix_b.pos_y][pix_b.pos_x+0];
    P_B = imgY[pix_b.pos_y][pix_b.pos_x+1];
    P_C = imgY[pix_b.pos_y][pix_b.pos_x+2];
    P_D = imgY[pix_b.pos_y][pix_b.pos_x+3];
    P_E = imgY[pix_b.pos_y][pix_b.pos_x+4];
    P_F = imgY[pix_b.pos_y][pix_b.pos_x+5];
    P_G = imgY[pix_b.pos_y][pix_b.pos_x+6];
    P_H = imgY[pix_b.pos_y][pix_b.pos_x+7];
  }
  else
  {
    P_A = P_B = P_C = P_D = P_E = P_F = P_G = P_H = img->dc_pred_value_luma;
  }

  if (block_available_up_right)
  {
    P_I = imgY[pix_c.pos_y][pix_c.pos_x+0];
    P_J = imgY[pix_c.pos_y][pix_c.pos_x+1];
    P_K = imgY[pix_c.pos_y][pix_c.pos_x+2];
    P_L = imgY[pix_c.pos_y][pix_c.pos_x+3];
    P_M = imgY[pix_c.pos_y][pix_c.pos_x+4];
    P_N = imgY[pix_c.pos_y][pix_c.pos_x+5];
    P_O = imgY[pix_c.pos_y][pix_c.pos_x+6];
    P_P = imgY[pix_c.pos_y][pix_c.pos_x+7];

  }
  else
  {
    P_I = P_J = P_K = P_L = P_M = P_N = P_O = P_P = P_H;
  }

  if (block_available_left)
  {
    P_Q = imgY[pix_a[0].pos_y][pix_a[0].pos_x];
    P_R = imgY[pix_a[1].pos_y][pix_a[1].pos_x];
    P_S = imgY[pix_a[2].pos_y][pix_a[2].pos_x];
    P_T = imgY[pix_a[3].pos_y][pix_a[3].pos_x];
    P_U = imgY[pix_a[4].pos_y][pix_a[4].pos_x];
    P_V = imgY[pix_a[5].pos_y][pix_a[5].pos_x];
    P_W = imgY[pix_a[6].pos_y][pix_a[6].pos_x];
    P_X = imgY[pix_a[7].pos_y][pix_a[7].pos_x];
  }
  else
  {
    P_Q = P_R = P_S = P_T = P_U = P_V = P_W = P_X = img->dc_pred_value_luma;
  }

  if (block_available_up_left)
  {
    P_Z = imgY[pix_d.pos_y][pix_d.pos_x];
  }
  else
  {
    P_Z = img->dc_pred_value_luma;
  }
  
  LowPassForIntra8x8Pred(&(P_Z), block_available_up_left, block_available_up, block_available_left);

//img->mpr[x][y]
  switch(predmode)
  {
  case DC_PRED:
    s0 = 0;
    if (block_available_up && block_available_left)
    {   
      // no edge
      s0 = (P_A + P_B + P_C + P_D + P_E + P_F + P_G + P_H + P_Q + P_R + P_S + P_T + P_U + P_V + P_W + P_X + 8) >> 4;
    }
    else if (!block_available_up && block_available_left)
    {
      // upper edge
      s0 = (P_Q + P_R + P_S + P_T + P_U + P_V + P_W + P_X + 4) >> 3;             
    }
    else if (block_available_up && !block_available_left)
    {
      // left edge
      s0 = (P_A + P_B + P_C + P_D + P_E + P_F + P_G + P_H + 4) >> 3;             
    }
    else //if (!block_available_up && !block_available_left)
    {
      // top left corner, nothing to predict from
      s0 = img->dc_pred_value_luma;                           
    }
    for(i = 0; i < 2*BLOCK_SIZE; i++)
      for(j = 0; j < 2*BLOCK_SIZE; j++)
        img->mpr[i+ioff][j+joff] = s0;
    break;

  case VERT_PRED:
    if (!block_available_up)
      printf ("warning: Intra_8x8_Vertical prediction mode not allowed at mb %d\n",img->current_mb_nr);

    for (i=0; i < 2*BLOCK_SIZE; i++)
    {
      img->mpr[i+ioff][0+joff] = 
      img->mpr[i+ioff][1+joff] = 
      img->mpr[i+ioff][2+joff] = 
      img->mpr[i+ioff][3+joff] = 
      img->mpr[i+ioff][4+joff] = 
      img->mpr[i+ioff][5+joff] = 
      img->mpr[i+ioff][6+joff] = 
      img->mpr[i+ioff][7+joff] = (&P_A)[i];
    }
    break;
  case HOR_PRED:
    if (!block_available_left)
      printf ("warning: Intra_8x8_Horizontal prediction mode not allowed at mb %d\n",img->current_mb_nr);

    for (j=0; j < 2*BLOCK_SIZE; j++)
    {
      img->mpr[0+ioff][j+joff]  = 
      img->mpr[1+ioff][j+joff]  = 
      img->mpr[2+ioff][j+joff]  = 
      img->mpr[3+ioff][j+joff]  = 
      img->mpr[4+ioff][j+joff]  = 
      img->mpr[5+ioff][j+joff]  = 
      img->mpr[6+ioff][j+joff]  = 
      img->mpr[7+ioff][j+joff]  = (&P_Q)[j];
    }
    break;

  case DIAG_DOWN_LEFT_PRED:
    if (!block_available_up)
      printf ("warning: Intra_8x8_Diagonal_Down_Left prediction mode not allowed at mb %d\n",img->current_mb_nr);
    // Mode DIAG_DOWN_LEFT_PRED
    img->mpr[0+ioff][0+joff] = (P_A + P_C + 2*(P_B) + 2) >> 2;
    img->mpr[0+ioff][1+joff] = 
    img->mpr[1+ioff][0+joff] = (P_B + P_D + 2*(P_C) + 2) >> 2;
    img->mpr[0+ioff][2+joff] =
    img->mpr[1+ioff][1+joff] =
    img->mpr[2+ioff][0+joff] = (P_C + P_E + 2*(P_D) + 2) >> 2;
    img->mpr[0+ioff][3+joff] = 
    img->mpr[1+ioff][2+joff] = 
    img->mpr[2+ioff][1+joff] = 
    img->mpr[3+ioff][0+joff] = (P_D + P_F + 2*(P_E) + 2) >> 2;
    img->mpr[0+ioff][4+joff] = 
    img->mpr[1+ioff][3+joff] = 
    img->mpr[2+ioff][2+joff] = 
    img->mpr[3+ioff][1+joff] = 
    img->mpr[4+ioff][0+joff] = (P_E + P_G + 2*(P_F) + 2) >> 2;
    img->mpr[0+ioff][5+joff] = 
    img->mpr[1+ioff][4+joff] = 
    img->mpr[2+ioff][3+joff] = 
    img->mpr[3+ioff][2+joff] = 
    img->mpr[4+ioff][1+joff] = 
    img->mpr[5+ioff][0+joff] = (P_F + P_H + 2*(P_G) + 2) >> 2;
    img->mpr[0+ioff][6+joff] = 
    img->mpr[1+ioff][5+joff] = 
    img->mpr[2+ioff][4+joff] = 
    img->mpr[3+ioff][3+joff] = 
    img->mpr[4+ioff][2+joff] = 
    img->mpr[5+ioff][1+joff] = 
    img->mpr[6+ioff][0+joff] = (P_G + P_I + 2*(P_H) + 2) >> 2;
    img->mpr[0+ioff][7+joff] = 
    img->mpr[1+ioff][6+joff] = 
    img->mpr[2+ioff][5+joff] = 
    img->mpr[3+ioff][4+joff] = 
    img->mpr[4+ioff][3+joff] = 
    img->mpr[5+ioff][2+joff] = 
    img->mpr[6+ioff][1+joff] = 
    img->mpr[7+ioff][0+joff] = (P_H + P_J + 2*(P_I) + 2) >> 2;
    img->mpr[1+ioff][7+joff] = 
    img->mpr[2+ioff][6+joff] = 
    img->mpr[3+ioff][5+joff] = 
    img->mpr[4+ioff][4+joff] = 
    img->mpr[5+ioff][3+joff] = 
    img->mpr[6+ioff][2+joff] = 
    img->mpr[7+ioff][1+joff] = (P_I + P_K + 2*(P_J) + 2) >> 2;
    img->mpr[2+ioff][7+joff] = 
    img->mpr[3+ioff][6+joff] = 
    img->mpr[4+ioff][5+joff] = 
    img->mpr[5+ioff][4+joff] = 
    img->mpr[6+ioff][3+joff] = 
    img->mpr[7+ioff][2+joff] = (P_J + P_L + 2*(P_K) + 2) >> 2;
    img->mpr[3+ioff][7+joff] = 
    img->mpr[4+ioff][6+joff] = 
    img->mpr[5+ioff][5+joff] = 
    img->mpr[6+ioff][4+joff] = 
    img->mpr[7+ioff][3+joff] = (P_K + P_M + 2*(P_L) + 2) >> 2;
    img->mpr[4+ioff][7+joff] = 
    img->mpr[5+ioff][6+joff] = 
    img->mpr[6+ioff][5+joff] = 
    img->mpr[7+ioff][4+joff] = (P_L + P_N + 2*(P_M) + 2) >> 2;
    img->mpr[5+ioff][7+joff] = 
    img->mpr[6+ioff][6+joff] = 
    img->mpr[7+ioff][5+joff] = (P_M + P_O + 2*(P_N) + 2) >> 2;
    img->mpr[6+ioff][7+joff] = 
    img->mpr[7+ioff][6+joff] = (P_N + P_P + 2*(P_O) + 2) >> 2;
    img->mpr[7+ioff][7+joff] = (P_O + 3*(P_P) + 2) >> 2;
    break;

  case VERT_LEFT_PRED:
    if (!block_available_up)
      printf ("warning: Intra_4x4_Vertical_Left prediction mode not allowed at mb %d\n",img->current_mb_nr);

    img->mpr[0+ioff][0+joff] = (P_A + P_B + 1) >> 1;
    img->mpr[1+ioff][0+joff] = 
    img->mpr[0+ioff][2+joff] = (P_B + P_C + 1) >> 1;
    img->mpr[2+ioff][0+joff] = 
    img->mpr[1+ioff][2+joff] = 
    img->mpr[0+ioff][4+joff] = (P_C + P_D + 1) >> 1;
    img->mpr[3+ioff][0+joff] = 
    img->mpr[2+ioff][2+joff] = 
    img->mpr[1+ioff][4+joff] = 
    img->mpr[0+ioff][6+joff] = (P_D + P_E + 1) >> 1;
    img->mpr[4+ioff][0+joff] = 
    img->mpr[3+ioff][2+joff] = 
    img->mpr[2+ioff][4+joff] = 
    img->mpr[1+ioff][6+joff] = (P_E + P_F + 1) >> 1;
    img->mpr[5+ioff][0+joff] = 
    img->mpr[4+ioff][2+joff] = 
    img->mpr[3+ioff][4+joff] = 
    img->mpr[2+ioff][6+joff] = (P_F + P_G + 1) >> 1;
    img->mpr[6+ioff][0+joff] = 
    img->mpr[5+ioff][2+joff] = 
    img->mpr[4+ioff][4+joff] = 
    img->mpr[3+ioff][6+joff] = (P_G + P_H + 1) >> 1;
    img->mpr[7+ioff][0+joff] = 
    img->mpr[6+ioff][2+joff] = 
    img->mpr[5+ioff][4+joff] = 
    img->mpr[4+ioff][6+joff] = (P_H + P_I + 1) >> 1;
    img->mpr[7+ioff][2+joff] = 
    img->mpr[6+ioff][4+joff] = 
    img->mpr[5+ioff][6+joff] = (P_I + P_J + 1) >> 1;
    img->mpr[7+ioff][4+joff] = 
    img->mpr[6+ioff][6+joff] = (P_J + P_K + 1) >> 1;
    img->mpr[7+ioff][6+joff] = (P_K + P_L + 1) >> 1;
    img->mpr[0+ioff][1+joff] = (P_A + P_C + 2*P_B + 2) >> 2;
    img->mpr[1+ioff][1+joff] = 
    img->mpr[0+ioff][3+joff] = (P_B + P_D + 2*P_C + 2) >> 2;
    img->mpr[2+ioff][1+joff] = 
    img->mpr[1+ioff][3+joff] = 
    img->mpr[0+ioff][5+joff] = (P_C + P_E + 2*P_D + 2) >> 2;
    img->mpr[3+ioff][1+joff] = 
    img->mpr[2+ioff][3+joff] = 
    img->mpr[1+ioff][5+joff] = 
    img->mpr[0+ioff][7+joff] = (P_D + P_F + 2*P_E + 2) >> 2;
    img->mpr[4+ioff][1+joff] =