libvpx: Pull from upstream

source/libvpx/vp9/common/vp9_reconinter.c

 /*
  *  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 <assert.h>
 
+#include "./vpx_scale_rtcd.h"
 #include "./vpx_config.h"
+
 #include "vpx/vpx_integer.h"
+
 #include "vp9/common/vp9_blockd.h"
 #include "vp9/common/vp9_filter.h"
 #include "vp9/common/vp9_reconinter.h"
 #include "vp9/common/vp9_reconintra.h"
-#include "./vpx_scale_rtcd.h"
 
-static int scale_value_x_with_scaling(int val,
-                                      const struct scale_factors *scale) {
-  return (val * scale->x_scale_fp >> VP9_REF_SCALE_SHIFT);
-}
-
-static int scale_value_y_with_scaling(int val,
-                                      const struct scale_factors *scale) {
-  return (val * scale->y_scale_fp >> VP9_REF_SCALE_SHIFT);
-}
-
-static int unscaled_value(int val, const struct scale_factors *scale) {
-  (void) scale;
-  return val;
-}
-
-static MV32 mv_q3_to_q4_with_scaling(const MV *mv,
-                                     const struct scale_factors *scale) {
-  const MV32 res = {
-    ((mv->row << 1) * scale->y_scale_fp >> VP9_REF_SCALE_SHIFT)
-        + scale->y_offset_q4,
-    ((mv->col << 1) * scale->x_scale_fp >> VP9_REF_SCALE_SHIFT)
-        + scale->x_offset_q4
-  };
-  return res;
-}
-
-static MV32 mv_q3_to_q4_without_scaling(const MV *mv,
-                                        const struct scale_factors *scale) {
-  const MV32 res = {
-     mv->row << 1,
-     mv->col << 1
-  };
-  return res;
-}
-
-static MV32 mv_q4_with_scaling(const MV *mv,
-                               const struct scale_factors *scale) {
-  const MV32 res = {
-    (mv->row * scale->y_scale_fp >> VP9_REF_SCALE_SHIFT) + scale->y_offset_q4,
-    (mv->col * scale->x_scale_fp >> VP9_REF_SCALE_SHIFT) + scale->x_offset_q4
-  };
-  return res;
-}
-
-static MV32 mv_q4_without_scaling(const MV *mv,
-                                  const struct scale_factors *scale) {
-  const MV32 res = {
-    mv->row,
-    mv->col
-  };
-  return res;
-}
-
-static void set_offsets_with_scaling(struct scale_factors *scale,
-                                     int row, int col) {
-  const int x_q4 = 16 * col;
-  const int y_q4 = 16 * row;
-
-  scale->x_offset_q4 = (x_q4 * scale->x_scale_fp >> VP9_REF_SCALE_SHIFT) & 0xf;
-  scale->y_offset_q4 = (y_q4 * scale->y_scale_fp >> VP9_REF_SCALE_SHIFT) & 0xf;
-}
-
-static void set_offsets_without_scaling(struct scale_factors *scale,
-                                        int row, int col) {
-  scale->x_offset_q4 = 0;
-  scale->y_offset_q4 = 0;
-}
-
-static int get_fixed_point_scale_factor(int other_size, int this_size) {
-  // Calculate scaling factor once for each reference frame
-  // and use fixed point scaling factors in decoding and encoding routines.
-  // Hardware implementations can calculate scale factor in device driver
-  // and use multiplication and shifting on hardware instead of division.
-  return (other_size << VP9_REF_SCALE_SHIFT) / this_size;
-}
-
-void vp9_setup_scale_factors_for_frame(struct scale_factors *scale,
-                                       int other_w, int other_h,
-                                       int this_w, int this_h) {
-  scale->x_scale_fp = get_fixed_point_scale_factor(other_w, this_w);
-  scale->x_offset_q4 = 0;  // calculated per-mb
-  scale->x_step_q4 = (16 * scale->x_scale_fp >> VP9_REF_SCALE_SHIFT);
-
-  scale->y_scale_fp = get_fixed_point_scale_factor(other_h, this_h);
-  scale->y_offset_q4 = 0;  // calculated per-mb
-  scale->y_step_q4 = (16 * scale->y_scale_fp >> VP9_REF_SCALE_SHIFT);
-
-  if ((other_w == this_w) && (other_h == this_h)) {
-    scale->scale_value_x = unscaled_value;
-    scale->scale_value_y = unscaled_value;
-    scale->set_scaled_offsets = set_offsets_without_scaling;
-    scale->scale_mv_q3_to_q4 = mv_q3_to_q4_without_scaling;
-    scale->scale_mv_q4 = mv_q4_without_scaling;
-  } else {
-    scale->scale_value_x = scale_value_x_with_scaling;
-    scale->scale_value_y = scale_value_y_with_scaling;
-    scale->set_scaled_offsets = set_offsets_with_scaling;
-    scale->scale_mv_q3_to_q4 = mv_q3_to_q4_with_scaling;
-    scale->scale_mv_q4 = mv_q4_with_scaling;
-  }
-
-  // TODO(agrange): Investigate the best choice of functions to use here
-  // for EIGHTTAP_SMOOTH. Since it is not interpolating, need to choose what
-  // to do at full-pel offsets. The current selection, where the filter is
-  // applied in one direction only, and not at all for 0,0, seems to give the
-  // best quality, but it may be worth trying an additional mode that does
-  // do the filtering on full-pel.
-  if (scale->x_step_q4 == 16) {
-    if (scale->y_step_q4 == 16) {
-      // No scaling in either direction.
-      scale->predict[0][0][0] = vp9_convolve_copy;
-      scale->predict[0][0][1] = vp9_convolve_avg;
-      scale->predict[0][1][0] = vp9_convolve8_vert;
-      scale->predict[0][1][1] = vp9_convolve8_avg_vert;
-      scale->predict[1][0][0] = vp9_convolve8_horiz;
-      scale->predict[1][0][1] = vp9_convolve8_avg_horiz;
-    } else {
-      // No scaling in x direction. Must always scale in the y direction.
-      scale->predict[0][0][0] = vp9_convolve8_vert;
-      scale->predict[0][0][1] = vp9_convolve8_avg_vert;
-      scale->predict[0][1][0] = vp9_convolve8_vert;
-      scale->predict[0][1][1] = vp9_convolve8_avg_vert;
-      scale->predict[1][0][0] = vp9_convolve8;
-      scale->predict[1][0][1] = vp9_convolve8_avg;
-    }
-  } else {
-    if (scale->y_step_q4 == 16) {
-      // No scaling in the y direction. Must always scale in the x direction.
-      scale->predict[0][0][0] = vp9_convolve8_horiz;
-      scale->predict[0][0][1] = vp9_convolve8_avg_horiz;
-      scale->predict[0][1][0] = vp9_convolve8;
-      scale->predict[0][1][1] = vp9_convolve8_avg;
-      scale->predict[1][0][0] = vp9_convolve8_horiz;
-      scale->predict[1][0][1] = vp9_convolve8_avg_horiz;
-    } else {
-      // Must always scale in both directions.
-      scale->predict[0][0][0] = vp9_convolve8;
-      scale->predict[0][0][1] = vp9_convolve8_avg;
-      scale->predict[0][1][0] = vp9_convolve8;
-      scale->predict[0][1][1] = vp9_convolve8_avg;
-      scale->predict[1][0][0] = vp9_convolve8;
-      scale->predict[1][0][1] = vp9_convolve8_avg;
-    }
-  }
-  // 2D subpel motion always gets filtered in both directions
-  scale->predict[1][1][0] = vp9_convolve8;
-  scale->predict[1][1][1] = vp9_convolve8_avg;
-}
 
 void vp9_setup_interp_filters(MACROBLOCKD *xd,
                               INTERPOLATIONFILTERTYPE mcomp_filter_type,
                               VP9_COMMON *cm) {
   if (xd->mode_info_context) {
     MB_MODE_INFO *mbmi = &xd->mode_info_context->mbmi;
 
     set_scale_factors(xd, mbmi->ref_frame[0] - 1, mbmi->ref_frame[1] - 1,
                       cm->active_ref_scale);
   }
@@ skipping 11 matching lines @@
       break;
     case BILINEAR:
       xd->subpix.filter_x = xd->subpix.filter_y = vp9_bilinear_filters;
       break;
   }
   assert(((intptr_t)xd->subpix.filter_x & 0xff) == 0);
 }
 
 void vp9_build_inter_predictor(const uint8_t *src, int src_stride,
                                uint8_t *dst, int dst_stride,
-                               const int_mv *src_mv,
+                               const MV *src_mv,
                                const struct scale_factors *scale,
-                               int w, int h, int weight,
+                               int w, int h, int ref,
                                const struct subpix_fn_table *subpix,
                                enum mv_precision precision) {
-  const MV32 mv = precision == MV_PRECISION_Q4
-                     ? scale->scale_mv_q4(&src_mv->as_mv, scale)
-                     : scale->scale_mv_q3_to_q4(&src_mv->as_mv, scale);
-  const int subpel_x = mv.col & 15;
-  const int subpel_y = mv.row & 15;
+  const int is_q4 = precision == MV_PRECISION_Q4;
+  const MV mv_q4 = { is_q4 ? src_mv->row : src_mv->row << 1,
+                     is_q4 ? src_mv->col : src_mv->col << 1 };
+  const MV32 mv = scale->scale_mv(&mv_q4, scale);
+  const int subpel_x = mv.col & SUBPEL_MASK;
+  const int subpel_y = mv.row & SUBPEL_MASK;
 
-  src += (mv.row >> 4) * src_stride + (mv.col >> 4);
-  scale->predict[!!subpel_x][!!subpel_y][weight](
+  src += (mv.row >> SUBPEL_BITS) * src_stride + (mv.col >> SUBPEL_BITS);
+  scale->predict[subpel_x != 0][subpel_y != 0][ref](
       src, src_stride, dst, dst_stride,
       subpix->filter_x[subpel_x], scale->x_step_q4,
       subpix->filter_y[subpel_y], scale->y_step_q4,
       w, h);
 }
 
 static INLINE int round_mv_comp_q4(int value) {
   return (value < 0 ? value - 2 : value + 2) / 4;
 }
 
-static int mi_mv_pred_row_q4(MACROBLOCKD *mb, int idx) {
-  const int temp = mb->mode_info_context->bmi[0].as_mv[idx].as_mv.row +
-                   mb->mode_info_context->bmi[1].as_mv[idx].as_mv.row +
-                   mb->mode_info_context->bmi[2].as_mv[idx].as_mv.row +
-                   mb->mode_info_context->bmi[3].as_mv[idx].as_mv.row;
-  return round_mv_comp_q4(temp);
-}
-
-static int mi_mv_pred_col_q4(MACROBLOCKD *mb, int idx) {
-  const int temp = mb->mode_info_context->bmi[0].as_mv[idx].as_mv.col +
-                   mb->mode_info_context->bmi[1].as_mv[idx].as_mv.col +
-                   mb->mode_info_context->bmi[2].as_mv[idx].as_mv.col +
-                   mb->mode_info_context->bmi[3].as_mv[idx].as_mv.col;
-  return round_mv_comp_q4(temp);
+static MV mi_mv_pred_q4(const MODE_INFO *mi, int idx) {
+  MV res = { round_mv_comp_q4(mi->bmi[0].as_mv[idx].as_mv.row +
+                              mi->bmi[1].as_mv[idx].as_mv.row +
+                              mi->bmi[2].as_mv[idx].as_mv.row +
+                              mi->bmi[3].as_mv[idx].as_mv.row),
+             round_mv_comp_q4(mi->bmi[0].as_mv[idx].as_mv.col +
+                              mi->bmi[1].as_mv[idx].as_mv.col +
+                              mi->bmi[2].as_mv[idx].as_mv.col +
+                              mi->bmi[3].as_mv[idx].as_mv.col) };
+  return res;
 }
 
 // TODO(jkoleszar): yet another mv clamping function :-(
-MV clamp_mv_to_umv_border_sb(const MV *src_mv,
-    int bwl, int bhl, int ss_x, int ss_y,
-    int mb_to_left_edge, int mb_to_top_edge,
-    int mb_to_right_edge, int mb_to_bottom_edge) {
-  /* If the MV points so far into the UMV border that no visible pixels
-   * are used for reconstruction, the subpel part of the MV can be
-   * discarded and the MV limited to 16 pixels with equivalent results.
-   */
-  const int spel_left = (VP9_INTERP_EXTEND + (4 << bwl)) << 4;
-  const int spel_right = spel_left - (1 << 4);
-  const int spel_top = (VP9_INTERP_EXTEND + (4 << bhl)) << 4;
-  const int spel_bottom = spel_top - (1 << 4);
-  MV clamped_mv;
-
+MV clamp_mv_to_umv_border_sb(const MACROBLOCKD *xd, const MV *src_mv,
+                             int bw, int bh, int ss_x, int ss_y) {
+  // If the MV points so far into the UMV border that no visible pixels
+  // are used for reconstruction, the subpel part of the MV can be
+  // discarded and the MV limited to 16 pixels with equivalent results.
+  const int spel_left = (VP9_INTERP_EXTEND + bw) << SUBPEL_BITS;
+  const int spel_right = spel_left - SUBPEL_SHIFTS;
+  const int spel_top = (VP9_INTERP_EXTEND + bh) << SUBPEL_BITS;
+  const int spel_bottom = spel_top - SUBPEL_SHIFTS;
+  MV clamped_mv = {
+    src_mv->row << (1 - ss_y),
+    src_mv->col << (1 - ss_x)
+  };
   assert(ss_x <= 1);
   assert(ss_y <= 1);
-  clamped_mv.col = clamp(src_mv->col << (1 - ss_x),
-                         (mb_to_left_edge << (1 - ss_x)) - spel_left,
-                         (mb_to_right_edge << (1 - ss_x)) + spel_right);
-  clamped_mv.row = clamp(src_mv->row << (1 - ss_y),
-                         (mb_to_top_edge << (1 - ss_y)) - spel_top,
-                         (mb_to_bottom_edge << (1 - ss_y)) + spel_bottom);
+
+  clamp_mv(&clamped_mv, (xd->mb_to_left_edge << (1 - ss_x)) - spel_left,
+                        (xd->mb_to_right_edge << (1 - ss_x)) + spel_right,
+                        (xd->mb_to_top_edge << (1 - ss_y)) - spel_top,
+                        (xd->mb_to_bottom_edge << (1 - ss_y)) + spel_bottom);
+
   return clamped_mv;
 }
 
 struct build_inter_predictors_args {
   MACROBLOCKD *xd;
-  int x;
-  int y;
-  uint8_t* dst[MAX_MB_PLANE];
-  int dst_stride[MAX_MB_PLANE];
-  uint8_t* pre[2][MAX_MB_PLANE];
-  int pre_stride[2][MAX_MB_PLANE];
+  int x, y;
 };
-static void build_inter_predictors(int plane, int block,
-                                   BLOCK_SIZE_TYPE bsize,
+
+static void build_inter_predictors(int plane, int block, BLOCK_SIZE bsize,
                                    int pred_w, int pred_h,
                                    void *argv) {
   const struct build_inter_predictors_args* const arg = argv;
-  MACROBLOCKD * const xd = arg->xd;
-  const int bwl = b_width_log2(bsize) - xd->plane[plane].subsampling_x;
-  const int bhl = b_height_log2(bsize) - xd->plane[plane].subsampling_y;
-  const int x = 4 * (block & ((1 << bwl) - 1)), y = 4 * (block >> bwl);
-  const int use_second_ref = xd->mode_info_context->mbmi.ref_frame[1] > 0;
-  int which_mv;
+  MACROBLOCKD *const xd = arg->xd;
+  struct macroblockd_plane *const pd = &xd->plane[plane];
+  const int bwl = b_width_log2(bsize) - pd->subsampling_x;
+  const int bw = 4 << bwl;
+  const int bh = plane_block_height(bsize, pd);
+  const int x = 4 * (block & ((1 << bwl) - 1));
+  const int y = 4 * (block >> bwl);
+  const MODE_INFO *const mi = xd->mode_info_context;
+  const int use_second_ref = mi->mbmi.ref_frame[1] > 0;
+  int ref;
 
-  assert(x < (4 << bwl));
-  assert(y < (4 << bhl));
-  assert(xd->mode_info_context->mbmi.sb_type < BLOCK_SIZE_SB8X8 ||
-         4 << pred_w == (4 << bwl));
-  assert(xd->mode_info_context->mbmi.sb_type < BLOCK_SIZE_SB8X8 ||
-         4 << pred_h == (4 << bhl));
+  assert(x < bw);
+  assert(y < bh);
+  assert(mi->mbmi.sb_type < BLOCK_8X8 || 4 << pred_w == bw);
+  assert(mi->mbmi.sb_type < BLOCK_8X8 || 4 << pred_h == bh);
 
-  for (which_mv = 0; which_mv < 1 + use_second_ref; ++which_mv) {
-    // source
-    const uint8_t * const base_pre = arg->pre[which_mv][plane];
-    const int pre_stride = arg->pre_stride[which_mv][plane];
-    const uint8_t *const pre = base_pre +
-        scaled_buffer_offset(x, y, pre_stride, &xd->scale_factor[which_mv]);
-    struct scale_factors * const scale = &xd->scale_factor[which_mv];
+  for (ref = 0; ref < 1 + use_second_ref; ++ref) {
+    struct scale_factors *const scale = &xd->scale_factor[ref];
+    struct buf_2d *const pre_buf = &pd->pre[ref];
+    struct buf_2d *const dst_buf = &pd->dst;
 
-    // dest
-    uint8_t *const dst = arg->dst[plane] + arg->dst_stride[plane] * y + x;
+    const uint8_t *const pre = pre_buf->buf + scaled_buffer_offset(x, y,
+                               pre_buf->stride, scale);
 
-    // motion vector
-    const MV *mv;
-    MV split_chroma_mv;
-    int_mv clamped_mv;
+    uint8_t *const dst = dst_buf->buf + dst_buf->stride * y + x;
 
-    if (xd->mode_info_context->mbmi.sb_type < BLOCK_SIZE_SB8X8) {
-      if (plane == 0) {
-        mv = &xd->mode_info_context->bmi[block].as_mv[which_mv].as_mv;
-      } else {
-        // TODO(jkoleszar): All chroma MVs in SPLITMV mode are taken as the
-        // same MV (the average of the 4 luma MVs) but we could do something
-        // smarter for non-4:2:0. Just punt for now, pending the changes to get
-        // rid of SPLITMV mode entirely.
-        split_chroma_mv.row = mi_mv_pred_row_q4(xd, which_mv);
-        split_chroma_mv.col = mi_mv_pred_col_q4(xd, which_mv);
-        mv = &split_chroma_mv;
-      }
-    } else {
-      mv = &xd->mode_info_context->mbmi.mv[which_mv].as_mv;
-    }
+    // TODO(jkoleszar): All chroma MVs in SPLITMV mode are taken as the
+    // same MV (the average of the 4 luma MVs) but we could do something
+    // smarter for non-4:2:0. Just punt for now, pending the changes to get
+    // rid of SPLITMV mode entirely.
+    const MV mv = mi->mbmi.sb_type < BLOCK_8X8
+               ? (plane == 0 ? mi->bmi[block].as_mv[ref].as_mv
+                             : mi_mv_pred_q4(mi, ref))
+               : mi->mbmi.mv[ref].as_mv;
 
-    /* TODO(jkoleszar): This clamping is done in the incorrect place for the
-     * scaling case. It needs to be done on the scaled MV, not the pre-scaling
-     * MV. Note however that it performs the subsampling aware scaling so
-     * that the result is always q4.
-     */
-    clamped_mv.as_mv = clamp_mv_to_umv_border_sb(mv, bwl, bhl,
-                                                 xd->plane[plane].subsampling_x,
-                                                 xd->plane[plane].subsampling_y,
-                                                 xd->mb_to_left_edge,
-                                                 xd->mb_to_top_edge,
-                                                 xd->mb_to_right_edge,
-                                                 xd->mb_to_bottom_edge);
+    // TODO(jkoleszar): This clamping is done in the incorrect place for the
+    // scaling case. It needs to be done on the scaled MV, not the pre-scaling
+    // MV. Note however that it performs the subsampling aware scaling so
+    // that the result is always q4.
+    const MV res_mv = clamp_mv_to_umv_border_sb(xd, &mv, bw, bh,
+                                                pd->subsampling_x,
+                                                pd->subsampling_y);
+
     scale->set_scaled_offsets(scale, arg->y + y, arg->x + x);
-
-    vp9_build_inter_predictor(pre, pre_stride,
-                              dst, arg->dst_stride[plane],
-                              &clamped_mv, &xd->scale_factor[which_mv],
-                              4 << pred_w, 4 << pred_h, which_mv,
+    vp9_build_inter_predictor(pre, pre_buf->stride, dst, dst_buf->stride,
+                              &res_mv, scale,
+                              4 << pred_w, 4 << pred_h, ref,
                               &xd->subpix, MV_PRECISION_Q4);
   }
 }
-void vp9_build_inter_predictors_sby(MACROBLOCKD *xd,
-                                    int mi_row,
-                                    int mi_col,
-                                    BLOCK_SIZE_TYPE bsize) {
-  struct build_inter_predictors_args args = {
-    xd, mi_col * MI_SIZE, mi_row * MI_SIZE,
-    {xd->plane[0].dst.buf, NULL, NULL}, {xd->plane[0].dst.stride, 0, 0},
-    {{xd->plane[0].pre[0].buf, NULL, NULL},
-     {xd->plane[0].pre[1].buf, NULL, NULL}},
-    {{xd->plane[0].pre[0].stride, 0, 0}, {xd->plane[0].pre[1].stride, 0, 0}},
-  };
 
-  foreach_predicted_block_in_plane(xd, bsize, 0, build_inter_predictors, &args);
+// TODO(jkoleszar): In principle, pred_w, pred_h are unnecessary, as we could
+// calculate the subsampled BLOCK_SIZE, but that type isn't defined for
+// sizes smaller than 16x16 yet.
+typedef void (*foreach_predicted_block_visitor)(int plane, int block,
+                                                BLOCK_SIZE bsize,
+                                                int pred_w, int pred_h,
+                                                void *arg);
+static INLINE void foreach_predicted_block_in_plane(
+    const MACROBLOCKD* const xd, BLOCK_SIZE bsize, int plane,
+    foreach_predicted_block_visitor visit, void *arg) {
+  int i, x, y;
+
+  // block sizes in number of 4x4 blocks log 2 ("*_b")
+  // 4x4=0, 8x8=2, 16x16=4, 32x32=6, 64x64=8
+  // subsampled size of the block
+  const int bwl = b_width_log2(bsize) - xd->plane[plane].subsampling_x;
+  const int bhl = b_height_log2(bsize) - xd->plane[plane].subsampling_y;
+
+  // size of the predictor to use.
+  int pred_w, pred_h;
+
+  if (xd->mode_info_context->mbmi.sb_type < BLOCK_8X8) {
+    assert(bsize == BLOCK_8X8);
+    pred_w = 0;
+    pred_h = 0;
+  } else {
+    pred_w = bwl;
+    pred_h = bhl;
+  }
+  assert(pred_w <= bwl);
+  assert(pred_h <= bhl);
+
+  // visit each subblock in raster order
+  i = 0;
+  for (y = 0; y < 1 << bhl; y += 1 << pred_h) {
+    for (x = 0; x < 1 << bwl; x += 1 << pred_w) {
+      visit(plane, i, bsize, pred_w, pred_h, arg);
+      i += 1 << pred_w;
+    }
+    i += (1 << (bwl + pred_h)) - (1 << bwl);
+  }
 }
-void vp9_build_inter_predictors_sbuv(MACROBLOCKD *xd,
-                                     int mi_row,
-                                     int mi_col,
-                                     BLOCK_SIZE_TYPE bsize) {
-  struct build_inter_predictors_args args = {
-    xd, mi_col * MI_SIZE, mi_row * MI_SIZE,
-#if CONFIG_ALPHA
-    {NULL, xd->plane[1].dst.buf, xd->plane[2].dst.buf,
-     xd->plane[3].dst.buf},
-    {0, xd->plane[1].dst.stride, xd->plane[1].dst.stride,
-     xd->plane[3].dst.stride},
-    {{NULL, xd->plane[1].pre[0].buf, xd->plane[2].pre[0].buf,
-      xd->plane[3].pre[0].buf},
-     {NULL, xd->plane[1].pre[1].buf, xd->plane[2].pre[1].buf,
-      xd->plane[3].pre[1].buf}},
-    {{0, xd->plane[1].pre[0].stride, xd->plane[1].pre[0].stride,
-      xd->plane[3].pre[0].stride},
-     {0, xd->plane[1].pre[1].stride, xd->plane[1].pre[1].stride,
-      xd->plane[3].pre[1].stride}},
-#else
-    {NULL, xd->plane[1].dst.buf, xd->plane[2].dst.buf},
-    {0, xd->plane[1].dst.stride, xd->plane[1].dst.stride},
-    {{NULL, xd->plane[1].pre[0].buf, xd->plane[2].pre[0].buf},
-     {NULL, xd->plane[1].pre[1].buf, xd->plane[2].pre[1].buf}},
-    {{0, xd->plane[1].pre[0].stride, xd->plane[1].pre[0].stride},
-     {0, xd->plane[1].pre[1].stride, xd->plane[1].pre[1].stride}},
-#endif
-  };
-  foreach_predicted_block_uv(xd, bsize, build_inter_predictors, &args);
+
+static void build_inter_predictors_for_planes(MACROBLOCKD *xd, BLOCK_SIZE bsize,
+                                              int mi_row, int mi_col,
+                                              int plane_from, int plane_to) {
+  int plane;
+  for (plane = plane_from; plane <= plane_to; ++plane) {
+    struct build_inter_predictors_args args = {
+      xd, mi_col * MI_SIZE, mi_row * MI_SIZE,
+    };
+    foreach_predicted_block_in_plane(xd, bsize, plane, build_inter_predictors,
+                                     &args);
+  }
 }
-void vp9_build_inter_predictors_sb(MACROBLOCKD *xd,
-                                   int mi_row, int mi_col,
-                                   BLOCK_SIZE_TYPE bsize) {
 
-  vp9_build_inter_predictors_sby(xd, mi_row, mi_col, bsize);
-  vp9_build_inter_predictors_sbuv(xd, mi_row, mi_col, bsize);
+void vp9_build_inter_predictors_sby(MACROBLOCKD *xd, int mi_row, int mi_col,
+                                    BLOCK_SIZE bsize) {
+  build_inter_predictors_for_planes(xd, bsize, mi_row, mi_col, 0, 0);
+}
+void vp9_build_inter_predictors_sbuv(MACROBLOCKD *xd, int mi_row, int mi_col,
+                                     BLOCK_SIZE bsize) {
+  build_inter_predictors_for_planes(xd, bsize, mi_row, mi_col, 1,
+                                    MAX_MB_PLANE - 1);
+}
+void vp9_build_inter_predictors_sb(MACROBLOCKD *xd, int mi_row, int mi_col,
+                                   BLOCK_SIZE bsize) {
+  build_inter_predictors_for_planes(xd, bsize, mi_row, mi_col, 0,
+                                    MAX_MB_PLANE - 1);
 }
 
 // TODO(dkovalev: find better place for this function)
 void vp9_setup_scale_factors(VP9_COMMON *cm, int i) {
   const int ref = cm->active_ref_idx[i];
   struct scale_factors *const sf = &cm->active_ref_scale[i];
   if (ref >= NUM_YV12_BUFFERS) {
-    memset(sf, 0, sizeof(*sf));
+    vp9_zero(*sf);
   } else {
     YV12_BUFFER_CONFIG *const fb = &cm->yv12_fb[ref];
     vp9_setup_scale_factors_for_frame(sf,
                                       fb->y_crop_width, fb->y_crop_height,
                                       cm->width, cm->height);
 
-    if (sf->x_scale_fp != VP9_REF_NO_SCALE ||
-        sf->y_scale_fp != VP9_REF_NO_SCALE)
+    if (vp9_is_scaled(sf))
       vp9_extend_frame_borders(fb, cm->subsampling_x, cm->subsampling_y);
   }
 }