michael@0: /*
michael@0:  *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
michael@0:  *
michael@0:  *  Use of this source code is governed by a BSD-style license
michael@0:  *  that can be found in the LICENSE file in the root of the source
michael@0:  *  tree. An additional intellectual property rights grant can be found
michael@0:  *  in the file PATENTS.  All contributing project authors may
michael@0:  *  be found in the AUTHORS file in the root of the source tree.
michael@0:  */
michael@0: 
michael@0: 
michael@0: #include "findnearmv.h"
michael@0: 
michael@0: const unsigned char vp8_mbsplit_offset[4][16] = {
michael@0:     { 0,  8,  0,  0,  0,  0,  0,  0,  0,  0,   0,  0,  0,  0,  0,  0},
michael@0:     { 0,  2,  0,  0,  0,  0,  0,  0,  0,  0,   0,  0,  0,  0,  0,  0},
michael@0:     { 0,  2,  8, 10,  0,  0,  0,  0,  0,  0,   0,  0,  0,  0,  0,  0},
michael@0:     { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9,  10, 11, 12, 13, 14, 15}
michael@0: };
michael@0: 
michael@0: /* Predict motion vectors using those from already-decoded nearby blocks.
michael@0:    Note that we only consider one 4x4 subblock from each candidate 16x16
michael@0:    macroblock.   */
michael@0: void vp8_find_near_mvs
michael@0: (
michael@0:     MACROBLOCKD *xd,
michael@0:     const MODE_INFO *here,
michael@0:     int_mv *nearest,
michael@0:     int_mv *nearby,
michael@0:     int_mv *best_mv,
michael@0:     int cnt[4],
michael@0:     int refframe,
michael@0:     int *ref_frame_sign_bias
michael@0: )
michael@0: {
michael@0:     const MODE_INFO *above = here - xd->mode_info_stride;
michael@0:     const MODE_INFO *left = here - 1;
michael@0:     const MODE_INFO *aboveleft = above - 1;
michael@0:     int_mv            near_mvs[4];
michael@0:     int_mv           *mv = near_mvs;
michael@0:     int             *cntx = cnt;
michael@0:     enum {CNT_INTRA, CNT_NEAREST, CNT_NEAR, CNT_SPLITMV};
michael@0: 
michael@0:     /* Zero accumulators */
michael@0:     mv[0].as_int = mv[1].as_int = mv[2].as_int = 0;
michael@0:     cnt[0] = cnt[1] = cnt[2] = cnt[3] = 0;
michael@0: 
michael@0:     /* Process above */
michael@0:     if (above->mbmi.ref_frame != INTRA_FRAME)
michael@0:     {
michael@0:         if (above->mbmi.mv.as_int)
michael@0:         {
michael@0:             (++mv)->as_int = above->mbmi.mv.as_int;
michael@0:             mv_bias(ref_frame_sign_bias[above->mbmi.ref_frame], refframe, mv, ref_frame_sign_bias);
michael@0:             ++cntx;
michael@0:         }
michael@0: 
michael@0:         *cntx += 2;
michael@0:     }
michael@0: 
michael@0:     /* Process left */
michael@0:     if (left->mbmi.ref_frame != INTRA_FRAME)
michael@0:     {
michael@0:         if (left->mbmi.mv.as_int)
michael@0:         {
michael@0:             int_mv this_mv;
michael@0: 
michael@0:             this_mv.as_int = left->mbmi.mv.as_int;
michael@0:             mv_bias(ref_frame_sign_bias[left->mbmi.ref_frame], refframe, &this_mv, ref_frame_sign_bias);
michael@0: 
michael@0:             if (this_mv.as_int != mv->as_int)
michael@0:             {
michael@0:                 (++mv)->as_int = this_mv.as_int;
michael@0:                 ++cntx;
michael@0:             }
michael@0: 
michael@0:             *cntx += 2;
michael@0:         }
michael@0:         else
michael@0:             cnt[CNT_INTRA] += 2;
michael@0:     }
michael@0: 
michael@0:     /* Process above left */
michael@0:     if (aboveleft->mbmi.ref_frame != INTRA_FRAME)
michael@0:     {
michael@0:         if (aboveleft->mbmi.mv.as_int)
michael@0:         {
michael@0:             int_mv this_mv;
michael@0: 
michael@0:             this_mv.as_int = aboveleft->mbmi.mv.as_int;
michael@0:             mv_bias(ref_frame_sign_bias[aboveleft->mbmi.ref_frame], refframe, &this_mv, ref_frame_sign_bias);
michael@0: 
michael@0:             if (this_mv.as_int != mv->as_int)
michael@0:             {
michael@0:                 (++mv)->as_int = this_mv.as_int;
michael@0:                 ++cntx;
michael@0:             }
michael@0: 
michael@0:             *cntx += 1;
michael@0:         }
michael@0:         else
michael@0:             cnt[CNT_INTRA] += 1;
michael@0:     }
michael@0: 
michael@0:     /* If we have three distinct MV's ... */
michael@0:     if (cnt[CNT_SPLITMV])
michael@0:     {
michael@0:         /* See if above-left MV can be merged with NEAREST */
michael@0:         if (mv->as_int == near_mvs[CNT_NEAREST].as_int)
michael@0:             cnt[CNT_NEAREST] += 1;
michael@0:     }
michael@0: 
michael@0:     cnt[CNT_SPLITMV] = ((above->mbmi.mode == SPLITMV)
michael@0:                         + (left->mbmi.mode == SPLITMV)) * 2
michael@0:                        + (aboveleft->mbmi.mode == SPLITMV);
michael@0: 
michael@0:     /* Swap near and nearest if necessary */
michael@0:     if (cnt[CNT_NEAR] > cnt[CNT_NEAREST])
michael@0:     {
michael@0:         int tmp;
michael@0:         tmp = cnt[CNT_NEAREST];
michael@0:         cnt[CNT_NEAREST] = cnt[CNT_NEAR];
michael@0:         cnt[CNT_NEAR] = tmp;
michael@0:         tmp = near_mvs[CNT_NEAREST].as_int;
michael@0:         near_mvs[CNT_NEAREST].as_int = near_mvs[CNT_NEAR].as_int;
michael@0:         near_mvs[CNT_NEAR].as_int = tmp;
michael@0:     }
michael@0: 
michael@0:     /* Use near_mvs[0] to store the "best" MV */
michael@0:     if (cnt[CNT_NEAREST] >= cnt[CNT_INTRA])
michael@0:         near_mvs[CNT_INTRA] = near_mvs[CNT_NEAREST];
michael@0: 
michael@0:     /* Set up return values */
michael@0:     best_mv->as_int = near_mvs[0].as_int;
michael@0:     nearest->as_int = near_mvs[CNT_NEAREST].as_int;
michael@0:     nearby->as_int = near_mvs[CNT_NEAR].as_int;
michael@0: }
michael@0: 
michael@0: 
michael@0: static void invert_and_clamp_mvs(int_mv *inv, int_mv *src, MACROBLOCKD *xd)
michael@0: {
michael@0:     inv->as_mv.row = src->as_mv.row * -1;
michael@0:     inv->as_mv.col = src->as_mv.col * -1;
michael@0:     vp8_clamp_mv2(inv, xd);
michael@0:     vp8_clamp_mv2(src, xd);
michael@0: }
michael@0: 
michael@0: 
michael@0: int vp8_find_near_mvs_bias
michael@0: (
michael@0:     MACROBLOCKD *xd,
michael@0:     const MODE_INFO *here,
michael@0:     int_mv mode_mv_sb[2][MB_MODE_COUNT],
michael@0:     int_mv best_mv_sb[2],
michael@0:     int cnt[4],
michael@0:     int refframe,
michael@0:     int *ref_frame_sign_bias
michael@0: )
michael@0: {
michael@0:     int sign_bias = ref_frame_sign_bias[refframe];
michael@0: 
michael@0:     vp8_find_near_mvs(xd,
michael@0:                       here,
michael@0:                       &mode_mv_sb[sign_bias][NEARESTMV],
michael@0:                       &mode_mv_sb[sign_bias][NEARMV],
michael@0:                       &best_mv_sb[sign_bias],
michael@0:                       cnt,
michael@0:                       refframe,
michael@0:                       ref_frame_sign_bias);
michael@0: 
michael@0:     invert_and_clamp_mvs(&mode_mv_sb[!sign_bias][NEARESTMV],
michael@0:                          &mode_mv_sb[sign_bias][NEARESTMV], xd);
michael@0:     invert_and_clamp_mvs(&mode_mv_sb[!sign_bias][NEARMV],
michael@0:                          &mode_mv_sb[sign_bias][NEARMV], xd);
michael@0:     invert_and_clamp_mvs(&best_mv_sb[!sign_bias],
michael@0:                          &best_mv_sb[sign_bias], xd);
michael@0: 
michael@0:     return sign_bias;
michael@0: }
michael@0: 
michael@0: 
michael@0: vp8_prob *vp8_mv_ref_probs(
michael@0:     vp8_prob p[VP8_MVREFS-1], const int near_mv_ref_ct[4]
michael@0: )
michael@0: {
michael@0:     p[0] = vp8_mode_contexts [near_mv_ref_ct[0]] [0];
michael@0:     p[1] = vp8_mode_contexts [near_mv_ref_ct[1]] [1];
michael@0:     p[2] = vp8_mode_contexts [near_mv_ref_ct[2]] [2];
michael@0:     p[3] = vp8_mode_contexts [near_mv_ref_ct[3]] [3];
michael@0:     /*p[3] = vp8_mode_contexts [near_mv_ref_ct[1] + near_mv_ref_ct[2] + near_mv_ref_ct[3]] [3];*/
michael@0:     return p;
michael@0: }
michael@0: