text: /*
   *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
   *
   *  Use of this source code is governed by a BSD-style license
   *  that can be found in the LICENSE file in the root of the source
   *  tree. An additional intellectual property rights grant can be found
   *  in the file PATENTS.  All contributing project authors may
   *  be found in the AUTHORS file in the root of the source tree.
   */
  
  
  #include "vpx_ports/config.h"
  #include "recon.h"
  #include "vpx_mem/vpx_mem.h"
  #include "reconintra.h"
  
  void vp8_predict_intra4x4(BLOCKD *x,
                            int b_mode,
                            unsigned char *predictor)
  {
      int i, r, c;
  
      unsigned char *Above = *(x->base_dst) + x->dst - x->dst_stride;
      unsigned char Left[4];
      unsigned char top_left = Above[-1];
  
      Left[0] = (*(x->base_dst))[x->dst - 1];
      Left[1] = (*(x->base_dst))[x->dst - 1 + x->dst_stride];
      Left[2] = (*(x->base_dst))[x->dst - 1 + 2 * x->dst_stride];
      Left[3] = (*(x->base_dst))[x->dst - 1 + 3 * x->dst_stride];
  
      switch (b_mode)
      {
      case B_DC_PRED:
      {
          int expected_dc = 0;
  
          for (i = 0; i < 4; i++)
          {
              expected_dc += Above[i];
              expected_dc += Left[i];
          }
  
          expected_dc = (expected_dc + 4) >> 3;
  
          for (r = 0; r < 4; r++)
          {
              for (c = 0; c < 4; c++)
              {
                  predictor[c] = expected_dc;
              }
  
              predictor += 16;
          }
      }
      break;
      case B_TM_PRED:
      {
          /* prediction similar to true_motion prediction */
          for (r = 0; r < 4; r++)
          {
              for (c = 0; c < 4; c++)
              {
                  int pred = Above[c] - top_left + Left[r];
  
                  if (pred < 0)
                      pred = 0;
  
                  if (pred > 255)
                      pred = 255;
  
                  predictor[c] = pred;
              }
  
              predictor += 16;
          }
      }
      break;
  
      case B_VE_PRED:
      {
  
          unsigned int ap[4];
          ap[0] = (top_left  + 2 * Above[0] + Above[1] + 2) >> 2;
          ap[1] = (Above[0] + 2 * Above[1] + Above[2] + 2) >> 2;
          ap[2] = (Above[1] + 2 * Above[2] + Above[3] + 2) >> 2;
          ap[3] = (Above[2] + 2 * Above[3] + Above[4] + 2) >> 2;
  
          for (r = 0; r < 4; r++)
          {
              for (c = 0; c < 4; c++)
              {
  
                  predictor[c] = ap[c];
              }
  
              predictor += 16;
          }
  
      }
      break;
  
  
      case B_HE_PRED:
      {
  
          unsigned int lp[4];
          lp[0] = (top_left + 2 * Left[0] + Left[1] + 2) >> 2;
          lp[1] = (Left[0] + 2 * Left[1] + Left[2] + 2) >> 2;
          lp[2] = (Left[1] + 2 * Left[2] + Left[3] + 2) >> 2;
          lp[3] = (Left[2] + 2 * Left[3] + Left[3] + 2) >> 2;
  
          for (r = 0; r < 4; r++)
          {
              for (c = 0; c < 4; c++)
              {
                  predictor[c] = lp[r];
              }
  
              predictor += 16;
          }
      }
      break;
      case B_LD_PRED:
      {
          unsigned char *ptr = Above;
          predictor[0 * 16 + 0] = (ptr[0] + ptr[1] * 2 + ptr[2] + 2) >> 2;
          predictor[0 * 16 + 1] =
              predictor[1 * 16 + 0] = (ptr[1] + ptr[2] * 2 + ptr[3] + 2) >> 2;
          predictor[0 * 16 + 2] =
              predictor[1 * 16 + 1] =
                  predictor[2 * 16 + 0] = (ptr[2] + ptr[3] * 2 + ptr[4] + 2) >> 2;
          predictor[0 * 16 + 3] =
              predictor[1 * 16 + 2] =
                  predictor[2 * 16 + 1] =
                      predictor[3 * 16 + 0] = (ptr[3] + ptr[4] * 2 + ptr[5] + 2) >> 2;
          predictor[1 * 16 + 3] =
              predictor[2 * 16 + 2] =
                  predictor[3 * 16 + 1] = (ptr[4] + ptr[5] * 2 + ptr[6] + 2) >> 2;
          predictor[2 * 16 + 3] =
              predictor[3 * 16 + 2] = (ptr[5] + ptr[6] * 2 + ptr[7] + 2) >> 2;
          predictor[3 * 16 + 3] = (ptr[6] + ptr[7] * 2 + ptr[7] + 2) >> 2;
  
      }
      break;
      case B_RD_PRED:
      {
  
          unsigned char pp[9];
  
          pp[0] = Left[3];
          pp[1] = Left[2];
          pp[2] = Left[1];
          pp[3] = Left[0];
          pp[4] = top_left;
          pp[5] = Above[0];
          pp[6] = Above[1];
          pp[7] = Above[2];
          pp[8] = Above[3];
  
          predictor[3 * 16 + 0] = (pp[0] + pp[1] * 2 + pp[2] + 2) >> 2;
          predictor[3 * 16 + 1] =
              predictor[2 * 16 + 0] = (pp[1] + pp[2] * 2 + pp[3] + 2) >> 2;
          predictor[3 * 16 + 2] =
              predictor[2 * 16 + 1] =
                  predictor[1 * 16 + 0] = (pp[2] + pp[3] * 2 + pp[4] + 2) >> 2;
          predictor[3 * 16 + 3] =
              predictor[2 * 16 + 2] =
                  predictor[1 * 16 + 1] =
                      predictor[0 * 16 + 0] = (pp[3] + pp[4] * 2 + pp[5] + 2) >> 2;
          predictor[2 * 16 + 3] =
              predictor[1 * 16 + 2] =
                  predictor[0 * 16 + 1] = (pp[4] + pp[5] * 2 + pp[6] + 2) >> 2;
          predictor[1 * 16 + 3] =
              predictor[0 * 16 + 2] = (pp[5] + pp[6] * 2 + pp[7] + 2) >> 2;
          predictor[0 * 16 + 3] = (pp[6] + pp[7] * 2 + pp[8] + 2) >> 2;
  
      }
      break;
      case B_VR_PRED:
      {
  
          unsigned char pp[9];
  
          pp[0] = Left[3];
          pp[1] = Left[2];
          pp[2] = Left[1];
          pp[3] = Left[0];
          pp[4] = top_left;
          pp[5] = Above[0];
          pp[6] = Above[1];
          pp[7] = Above[2];
          pp[8] = Above[3];
  
  
          predictor[3 * 16 + 0] = (pp[1] + pp[2] * 2 + pp[3] + 2) >> 2;
          predictor[2 * 16 + 0] = (pp[2] + pp[3] * 2 + pp[4] + 2) >> 2;
          predictor[3 * 16 + 1] =
              predictor[1 * 16 + 0] = (pp[3] + pp[4] * 2 + pp[5] + 2) >> 2;
          predictor[2 * 16 + 1] =
              predictor[0 * 16 + 0] = (pp[4] + pp[5] + 1) >> 1;
          predictor[3 * 16 + 2] =
              predictor[1 * 16 + 1] = (pp[4] + pp[5] * 2 + pp[6] + 2) >> 2;
          predictor[2 * 16 + 2] =
              predictor[0 * 16 + 1] = (pp[5] + pp[6] + 1) >> 1;
          predictor[3 * 16 + 3] =
              predictor[1 * 16 + 2] = (pp[5] + pp[6] * 2 + pp[7] + 2) >> 2;
          predictor[2 * 16 + 3] =
              predictor[0 * 16 + 2] = (pp[6] + pp[7] + 1) >> 1;
          predictor[1 * 16 + 3] = (pp[6] + pp[7] * 2 + pp[8] + 2) >> 2;
          predictor[0 * 16 + 3] = (pp[7] + pp[8] + 1) >> 1;
  
      }
      break;
      case B_VL_PRED:
      {
  
          unsigned char *pp = Above;
  
          predictor[0 * 16 + 0] = (pp[0] + pp[1] + 1) >> 1;
          predictor[1 * 16 + 0] = (pp[0] + pp[1] * 2 + pp[2] + 2) >> 2;
          predictor[2 * 16 + 0] =
              predictor[0 * 16 + 1] = (pp[1] + pp[2] + 1) >> 1;
          predictor[1 * 16 + 1] =
              predictor[3 * 16 + 0] = (pp[1] + pp[2] * 2 + pp[3] + 2) >> 2;
          predictor[2 * 16 + 1] =
              predictor[0 * 16 + 2] = (pp[2] + pp[3] + 1) >> 1;
          predictor[3 * 16 + 1] =
              predictor[1 * 16 + 2] = (pp[2] + pp[3] * 2 + pp[4] + 2) >> 2;
          predictor[0 * 16 + 3] =
              predictor[2 * 16 + 2] = (pp[3] + pp[4] + 1) >> 1;
          predictor[1 * 16 + 3] =
              predictor[3 * 16 + 2] = (pp[3] + pp[4] * 2 + pp[5] + 2) >> 2;
          predictor[2 * 16 + 3] = (pp[4] + pp[5] * 2 + pp[6] + 2) >> 2;
          predictor[3 * 16 + 3] = (pp[5] + pp[6] * 2 + pp[7] + 2) >> 2;
      }
      break;
  
      case B_HD_PRED:
      {
          unsigned char pp[9];
          pp[0] = Left[3];
          pp[1] = Left[2];
          pp[2] = Left[1];
          pp[3] = Left[0];
          pp[4] = top_left;
          pp[5] = Above[0];
          pp[6] = Above[1];
          pp[7] = Above[2];
          pp[8] = Above[3];
  
  
          predictor[3 * 16 + 0] = (pp[0] + pp[1] + 1) >> 1;
          predictor[3 * 16 + 1] = (pp[0] + pp[1] * 2 + pp[2] + 2) >> 2;
          predictor[2 * 16 + 0] =
              predictor[3 * 16 + 2] = (pp[1] + pp[2] + 1) >> 1;
          predictor[2 * 16 + 1] =
              predictor[3 * 16 + 3] = (pp[1] + pp[2] * 2 + pp[3] + 2) >> 2;
          predictor[2 * 16 + 2] =
              predictor[1 * 16 + 0] = (pp[2] + pp[3] + 1) >> 1;
          predictor[2 * 16 + 3] =
              predictor[1 * 16 + 1] = (pp[2] + pp[3] * 2 + pp[4] + 2) >> 2;
          predictor[1 * 16 + 2] =
              predictor[0 * 16 + 0] = (pp[3] + pp[4] + 1) >> 1;
          predictor[1 * 16 + 3] =
              predictor[0 * 16 + 1] = (pp[3] + pp[4] * 2 + pp[5] + 2) >> 2;
          predictor[0 * 16 + 2] = (pp[4] + pp[5] * 2 + pp[6] + 2) >> 2;
          predictor[0 * 16 + 3] = (pp[5] + pp[6] * 2 + pp[7] + 2) >> 2;
      }
      break;
  
  
      case B_HU_PRED:
      {
          unsigned char *pp = Left;
          predictor[0 * 16 + 0] = (pp[0] + pp[1] + 1) >> 1;
          predictor[0 * 16 + 1] = (pp[0] + pp[1] * 2 + pp[2] + 2) >> 2;
          predictor[0 * 16 + 2] =
              predictor[1 * 16 + 0] = (pp[1] + pp[2] + 1) >> 1;
          predictor[0 * 16 + 3] =
              predictor[1 * 16 + 1] = (pp[1] + pp[2] * 2 + pp[3] + 2) >> 2;
          predictor[1 * 16 + 2] =
              predictor[2 * 16 + 0] = (pp[2] + pp[3] + 1) >> 1;
          predictor[1 * 16 + 3] =
              predictor[2 * 16 + 1] = (pp[2] + pp[3] * 2 + pp[3] + 2) >> 2;
          predictor[2 * 16 + 2] =
              predictor[2 * 16 + 3] =
                  predictor[3 * 16 + 0] =
                      predictor[3 * 16 + 1] =
                          predictor[3 * 16 + 2] =
                              predictor[3 * 16 + 3] = pp[3];
      }
      break;
  
  
      }
  }
  /* copy 4 bytes from the above right down so that the 4x4 prediction modes using pixels above and
   * to the right prediction have filled in pixels to use.
   */
  void vp8_intra_prediction_down_copy(MACROBLOCKD *x)
  {
      unsigned char *above_right = *(x->block[0].base_dst) + x->block[0].dst - x->block[0].dst_stride + 16;
  
      unsigned int *src_ptr = (unsigned int *)above_right;
      unsigned int *dst_ptr0 = (unsigned int *)(above_right + 4 * x->block[0].dst_stride);
      unsigned int *dst_ptr1 = (unsigned int *)(above_right + 8 * x->block[0].dst_stride);
      unsigned int *dst_ptr2 = (unsigned int *)(above_right + 12 * x->block[0].dst_stride);
  
      *dst_ptr0 = *src_ptr;
      *dst_ptr1 = *src_ptr;
      *dst_ptr2 = *src_ptr;
  }
  
  
  