ref: 6e364a57c0bf7477b35284e7acbcf776e1d5ec3e
dir: /vp8/common/findnearmv.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 "findnearmv.h"
#include "vp8/encoder/variance.h"
#include <limits.h>
const unsigned char vp8_mbsplit_offset[4][16] = {
{ 0, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
{ 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
{ 0, 2, 8, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
{ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15}
};
static void lower_mv_precision(int_mv *mv, int usehp)
{
#if CONFIG_NEWMVENTROPY
if (!usehp || !vp8_use_nmv_hp(&mv->as_mv)) {
#else
if (!usehp) {
#endif
if (mv->as_mv.row & 1)
mv->as_mv.row += (mv->as_mv.row > 0 ? -1 : 1);
if (mv->as_mv.col & 1)
mv->as_mv.col += (mv->as_mv.col > 0 ? -1 : 1);
}
}
/* Predict motion vectors using those from already-decoded nearby blocks.
Note that we only consider one 4x4 subblock from each candidate 16x16
macroblock. */
void vp8_find_near_mvs
(
MACROBLOCKD *xd,
const MODE_INFO *here,
const MODE_INFO *lf_here,
int_mv *nearest,
int_mv *nearby,
int_mv *best_mv,
int cnt[4],
int refframe,
int *ref_frame_sign_bias) {
const MODE_INFO *above = here - xd->mode_info_stride;
const MODE_INFO *left = here - 1;
const MODE_INFO *aboveleft = above - 1;
const MODE_INFO *third = NULL;
int_mv near_mvs[4];
int_mv *mv = near_mvs;
int *cntx = cnt;
enum {CNT_INTRA, CNT_NEAREST, CNT_NEAR, CNT_SPLITMV};
#if CONFIG_NEWBESTREFMV
int_mv *ref_mv = xd->ref_mv;
#endif
/* Zero accumulators */
mv[0].as_int = mv[1].as_int = mv[2].as_int = 0;
cnt[0] = cnt[1] = cnt[2] = cnt[3] = 0;
#if CONFIG_NEWBESTREFMV
ref_mv[0].as_int = ref_mv[1].as_int
= ref_mv[2].as_int
= ref_mv[3].as_int
= 0;
#endif
/* Process above */
if (above->mbmi.ref_frame != INTRA_FRAME) {
if (above->mbmi.mv[0].as_int) {
++ mv;
mv->as_int = above->mbmi.mv[0].as_int;
mv_bias(ref_frame_sign_bias[above->mbmi.ref_frame],
refframe, mv, ref_frame_sign_bias);
#if CONFIG_NEWBESTREFMV
ref_mv[0].as_int = mv->as_int;
#endif
++cntx;
}
*cntx += 2;
}
/* Process left */
if (left->mbmi.ref_frame != INTRA_FRAME) {
if (left->mbmi.mv[0].as_int) {
int_mv this_mv;
this_mv.as_int = left->mbmi.mv[0].as_int;
mv_bias(ref_frame_sign_bias[left->mbmi.ref_frame],
refframe, &this_mv, ref_frame_sign_bias);
#if CONFIG_NEWBESTREFMV
ref_mv[1].as_int = this_mv.as_int;
#endif
if (this_mv.as_int != mv->as_int) {
++ mv;
mv->as_int = this_mv.as_int;
++ cntx;
}
*cntx += 2;
} else
cnt[CNT_INTRA] += 2;
}
/* Process above left or the one from last frame */
if (aboveleft->mbmi.ref_frame != INTRA_FRAME ||
(lf_here->mbmi.ref_frame == LAST_FRAME && refframe == LAST_FRAME)) {
if (aboveleft->mbmi.mv[0].as_int) {
third = aboveleft;
#if CONFIG_NEWBESTREFMV
ref_mv[2].as_int = aboveleft->mbmi.mv[0].as_int;
mv_bias(ref_frame_sign_bias[aboveleft->mbmi.ref_frame],
refframe, (ref_mv+2), ref_frame_sign_bias);
#endif
} else if (lf_here->mbmi.mv[0].as_int) {
third = lf_here;
}
#if CONFIG_NEWBESTREFMV
if (lf_here->mbmi.mv[0].as_int) {
ref_mv[3].as_int = lf_here->mbmi.mv[0].as_int;
mv_bias(ref_frame_sign_bias[lf_here->mbmi.ref_frame],
refframe, (ref_mv+3), ref_frame_sign_bias);
}
#endif
if (third) {
int_mv this_mv;
this_mv.as_int = third->mbmi.mv[0].as_int;
mv_bias(ref_frame_sign_bias[third->mbmi.ref_frame],
refframe, &this_mv, ref_frame_sign_bias);
if (this_mv.as_int != mv->as_int) {
++ mv;
mv->as_int = this_mv.as_int;
++ cntx;
}
*cntx += 1;
} else
cnt[CNT_INTRA] += 1;
}
/* If we have three distinct MV's ... */
if (cnt[CNT_SPLITMV]) {
/* See if the third MV can be merged with NEAREST */
if (mv->as_int == near_mvs[CNT_NEAREST].as_int)
cnt[CNT_NEAREST] += 1;
}
cnt[CNT_SPLITMV] = ((above->mbmi.mode == SPLITMV)
+ (left->mbmi.mode == SPLITMV)) * 2
+ (
lf_here->mbmi.mode == SPLITMV ||
aboveleft->mbmi.mode == SPLITMV);
/* Swap near and nearest if necessary */
if (cnt[CNT_NEAR] > cnt[CNT_NEAREST]) {
int tmp;
tmp = cnt[CNT_NEAREST];
cnt[CNT_NEAREST] = cnt[CNT_NEAR];
cnt[CNT_NEAR] = tmp;
tmp = near_mvs[CNT_NEAREST].as_int;
near_mvs[CNT_NEAREST].as_int = near_mvs[CNT_NEAR].as_int;
near_mvs[CNT_NEAR].as_int = tmp;
}
/* Use near_mvs[0] to store the "best" MV */
if (cnt[CNT_NEAREST] >= cnt[CNT_INTRA])
near_mvs[CNT_INTRA] = near_mvs[CNT_NEAREST];
/* Set up return values */
best_mv->as_int = near_mvs[0].as_int;
nearest->as_int = near_mvs[CNT_NEAREST].as_int;
nearby->as_int = near_mvs[CNT_NEAR].as_int;
/* Make sure that the 1/8th bits of the Mvs are zero if high_precision
* is not being used, by truncating the last bit towards 0
*/
lower_mv_precision(best_mv, xd->allow_high_precision_mv);
lower_mv_precision(nearest, xd->allow_high_precision_mv);
lower_mv_precision(nearby, xd->allow_high_precision_mv);
// TODO: move clamp outside findnearmv
vp8_clamp_mv2(nearest, xd);
vp8_clamp_mv2(nearby, xd);
vp8_clamp_mv2(best_mv, xd);
}
vp8_prob *vp8_mv_ref_probs(VP8_COMMON *pc,
vp8_prob p[VP8_MVREFS - 1], const int near_mv_ref_ct[4]
) {
p[0] = pc->fc.vp8_mode_contexts [near_mv_ref_ct[0]] [0];
p[1] = pc->fc.vp8_mode_contexts [near_mv_ref_ct[1]] [1];
p[2] = pc->fc.vp8_mode_contexts [near_mv_ref_ct[2]] [2];
p[3] = pc->fc.vp8_mode_contexts [near_mv_ref_ct[3]] [3];
return p;
}
#if CONFIG_NEWBESTREFMV
/* check a list of motion vectors by sad score using a number rows of pixels
* above and a number cols of pixels in the left to select the one with best
* score to use as ref motion vector
*/
void vp8_find_best_ref_mvs(MACROBLOCKD *xd,
unsigned char *ref_y_buffer,
int ref_y_stride,
int_mv *mvlist,
int_mv *best_mv,
int_mv *nearest,
int_mv *near) {
int i, j;
unsigned char *above_src;
unsigned char *left_src;
unsigned char *above_ref;
unsigned char *left_ref;
int sad;
int sad_scores[MAX_MV_REFS] = {0};
int_mv sorted_mvs[MAX_MV_REFS];
int zero_seen = FALSE;
// Default all to 0,0 if nothing else available
best_mv->as_int = nearest->as_int = near->as_int = 0;
vpx_memset(sorted_mvs, 0, sizeof(sorted_mvs));
above_src = xd->dst.y_buffer - xd->dst.y_stride * 3;
left_src = xd->dst.y_buffer - 3;
above_ref = ref_y_buffer - ref_y_stride * 3;
left_ref = ref_y_buffer - 3;
//for(i = 0; i < MAX_MV_REFS; ++i) {
// Limit search to the predicted best 4
for(i = 0; i < 4; ++i) {
int_mv this_mv;
int offset=0;
int row_offset, col_offset;
this_mv.as_int = mvlist[i].as_int;
// If we see a 0,0 vector for a second time we have reached the end of
// the list of valid candidate vectors.
if (!this_mv.as_int)
if (zero_seen)
break;
else
zero_seen = TRUE;
vp8_clamp_mv(&this_mv,
xd->mb_to_left_edge - LEFT_TOP_MARGIN + 16,
xd->mb_to_right_edge + RIGHT_BOTTOM_MARGIN,
xd->mb_to_top_edge - LEFT_TOP_MARGIN + 16,
xd->mb_to_bottom_edge + RIGHT_BOTTOM_MARGIN);
row_offset = (this_mv.as_mv.row > 0) ?
((this_mv.as_mv.row + 3) >> 3):((this_mv.as_mv.row + 4) >> 3);
col_offset = (this_mv.as_mv.col > 0) ?
((this_mv.as_mv.col + 3) >> 3):((this_mv.as_mv.col + 4) >> 3);
offset = ref_y_stride * row_offset + col_offset;
sad = 0;
if (xd->up_available)
sad += vp8_sad16x3_c(above_src, xd->dst.y_stride,
above_ref + offset, ref_y_stride, INT_MAX);
if (xd->left_available)
sad += vp8_sad3x16_c(left_src, xd->dst.y_stride,
left_ref + offset, ref_y_stride, INT_MAX);
// Add the entry to our list and then resort the list on score.
sad_scores[i] = sad;
sorted_mvs[i].as_int = this_mv.as_int;
j = i;
while (j > 0) {
if (sad_scores[j] < sad_scores[j-1]) {
sad_scores[j] = sad_scores[j-1];
sorted_mvs[j].as_int = sorted_mvs[j-1].as_int;
sad_scores[j-1] = sad;
sorted_mvs[j-1].as_int = this_mv.as_int;
j--;
} else
break;
}
}
// Set the best mv to the first entry in the sorted list
best_mv->as_int = sorted_mvs[0].as_int;
// Provided that there are non zero vectors available there will not
// be more than one 0,0 entry in the sorted list.
// The best ref mv is always set to the first entry (which gave the best
// results. The nearest is set to the first non zero vector if available and
// near to the second non zero vector if avaialable.
// We do not use 0,0 as a nearest or near as 0,0 has its own mode.
if ( sorted_mvs[0].as_int ) {
nearest->as_int = sorted_mvs[0].as_int;
if ( sorted_mvs[1].as_int )
near->as_int = sorted_mvs[1].as_int;
else
near->as_int = sorted_mvs[2].as_int;
} else {
nearest->as_int = sorted_mvs[1].as_int;
near->as_int = sorted_mvs[2].as_int;
}
// Copy back the re-ordered mv list
vpx_memcpy(mvlist, sorted_mvs, sizeof(sorted_mvs));
lower_mv_precision(best_mv, xd->allow_high_precision_mv);
vp8_clamp_mv2(best_mv, xd);
}
#endif // CONFIG_NEWBESTREFMV