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 /*

  *  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"

 void vp9_setup_interp_filters(MACROBLOCKD *xd,

                               INTERPOLATION_TYPE mcomp_filter_type,

                               VP9_COMMON *cm) {

   if (xd->mi_8x8 && xd->mi_8x8[0]) {

     MB_MODE_INFO *const mbmi = &xd->mi_8x8[0]->mbmi;

     set_scale_factors(xd, mbmi->ref_frame[0] - LAST_FRAME,

                           mbmi->ref_frame[1] - LAST_FRAME,

                           cm->active_ref_scale);

   } else {

     set_scale_factors(xd, -1, -1, cm->active_ref_scale);

   }

   xd->subpix.filter_x = xd->subpix.filter_y =

       vp9_get_filter_kernel(mcomp_filter_type == SWITCHABLE ?

                                EIGHTTAP : mcomp_filter_type);

   assert(((intptr_t)xd->subpix.filter_x & 0xff) == 0);

 }

 static void inter_predictor(const uint8_t *src, int src_stride,

                             uint8_t *dst, int dst_stride,

                             const MV32 *mv,

                             const struct scale_factors *scale,

                             int w, int h, int ref,

                             const struct subpix_fn_table *subpix,

                             int xs, int ys) {

   const int subpel_x = mv->col & SUBPEL_MASK;

   const int subpel_y = mv->row & SUBPEL_MASK;

   src += (mv->row >> SUBPEL_BITS) * src_stride + (mv->col >> SUBPEL_BITS);

   scale->sfc->predict[subpel_x != 0][subpel_y != 0][ref](

       src, src_stride, dst, dst_stride,

       subpix->filter_x[subpel_x], xs,

       subpix->filter_y[subpel_y], ys,

       w, h);

 }

 void vp9_build_inter_predictor(const uint8_t *src, int src_stride,

                                uint8_t *dst, int dst_stride,

                                const MV *src_mv,

                                const struct scale_factors *scale,

                                int w, int h, int ref,

                                const struct subpix_fn_table *subpix,

                                enum mv_precision precision) {

   const int is_q4 = precision == MV_PRECISION_Q4;

   const MV mv_q4 = { is_q4 ? src_mv->row : src_mv->row * 2,

                      is_q4 ? src_mv->col : src_mv->col * 2 };

   const struct scale_factors_common *sfc = scale->sfc;

   const MV32 mv = sfc->scale_mv(&mv_q4, scale);

   inter_predictor(src, src_stride, dst, dst_stride, &mv, scale,

                   w, h, ref, subpix, sfc->x_step_q4, sfc->y_step_q4);

 }

 static INLINE int round_mv_comp_q4(int value) {

   return (value < 0 ? value - 2 : value + 2) / 4;

 }

 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 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 << (1 - ss_y)),

     src_mv->col * (1 << (1 - ss_x))

   };

   assert(ss_x <= 1);

   assert(ss_y <= 1);

   clamp_mv(&clamped_mv,

            xd->mb_to_left_edge * (1 << (1 - ss_x)) - spel_left,

            xd->mb_to_right_edge * (1 << (1 - ss_x)) + spel_right,

            xd->mb_to_top_edge * (1 << (1 - ss_y)) - spel_top,

            xd->mb_to_bottom_edge * (1 << (1 - ss_y)) + spel_bottom);

   return clamped_mv;

 }

 // 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.

 static void build_inter_predictors(MACROBLOCKD *xd, int plane, int block,

                                    BLOCK_SIZE bsize, int pred_w, int pred_h,

                                    int mi_x, int mi_y) {

   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 *mi = xd->mi_8x8[0];

   const int is_compound = has_second_ref(&mi->mbmi);

   int ref;

   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 (ref = 0; ref < 1 + is_compound; ++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;

     uint8_t *const dst = dst_buf->buf + dst_buf->stride * y + x;

     // 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.

     // mv_precision precision is MV_PRECISION_Q4.

     const MV mv_q4 = clamp_mv_to_umv_border_sb(xd, &mv, bw, bh,

                                                pd->subsampling_x,

                                                pd->subsampling_y);

     uint8_t *pre;

     MV32 scaled_mv;

     int xs, ys;

     if (vp9_is_scaled(scale->sfc)) {

       pre = pre_buf->buf + scaled_buffer_offset(x, y, pre_buf->stride, scale);

       scale->sfc->set_scaled_offsets(scale, mi_y + y, mi_x + x);

       scaled_mv = scale->sfc->scale_mv(&mv_q4, scale);

       xs = scale->sfc->x_step_q4;

       ys = scale->sfc->y_step_q4;

     } else {

       pre = pre_buf->buf + (y * pre_buf->stride + x);

       scaled_mv.row = mv_q4.row;

       scaled_mv.col = mv_q4.col;

       xs = ys = 16;

     }

     inter_predictor(pre, pre_buf->stride, dst, dst_buf->stride,

                     &scaled_mv, scale,

                     4 << pred_w, 4 << pred_h, ref,

                     &xd->subpix, xs, ys);

   }

 }

 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) {

     const int mi_x = mi_col * MI_SIZE;

     const int mi_y = mi_row * MI_SIZE;

     const int bwl = b_width_log2(bsize) - xd->plane[plane].subsampling_x;

     const int bhl = b_height_log2(bsize) - xd->plane[plane].subsampling_y;

     if (xd->mi_8x8[0]->mbmi.sb_type < BLOCK_8X8) {

       int i = 0, x, y;

       assert(bsize == BLOCK_8X8);

       for (y = 0; y < 1 << bhl; ++y)

         for (x = 0; x < 1 << bwl; ++x)

           build_inter_predictors(xd, plane, i++, bsize, 0, 0, mi_x, mi_y);

     } else {

       build_inter_predictors(xd, plane, 0, bsize, bwl, bhl, mi_x, mi_y);

     }

   }

 }

 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];

   struct scale_factors_common *const sfc = &cm->active_ref_scale_comm[i];

   if (ref >= NUM_YV12_BUFFERS) {

     vp9_zero(*sf);

     vp9_zero(*sfc);

   } else {

     YV12_BUFFER_CONFIG *const fb = &cm->yv12_fb[ref];

     vp9_setup_scale_factors_for_frame(sf, sfc,

                                       fb->y_crop_width, fb->y_crop_height,

                                       cm->width, cm->height);

     if (vp9_is_scaled(sfc))

       vp9_extend_frame_borders(fb, cm->subsampling_x, cm->subsampling_y);

   }

 }