ref: 5e32036b97f8a154acf708a9fecdc19886e60c0e
dir: /vp9/encoder/vp9_encodemv.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 <math.h>
#include "vp9/common/vp9_common.h"
#include "vp9/common/vp9_entropymode.h"
#include "vp9/common/vp9_systemdependent.h"
#include "vp9/encoder/vp9_cost.h"
#include "vp9/encoder/vp9_encodemv.h"
static struct vp9_token mv_joint_encodings[MV_JOINTS];
static struct vp9_token mv_class_encodings[MV_CLASSES];
static struct vp9_token mv_fp_encodings[MV_FP_SIZE];
static struct vp9_token mv_class0_encodings[CLASS0_SIZE];
void vp9_entropy_mv_init() {
vp9_tokens_from_tree(mv_joint_encodings, vp9_mv_joint_tree);
vp9_tokens_from_tree(mv_class_encodings, vp9_mv_class_tree);
vp9_tokens_from_tree(mv_class0_encodings, vp9_mv_class0_tree);
vp9_tokens_from_tree(mv_fp_encodings, vp9_mv_fp_tree);
}
static void encode_mv_component(vp9_writer* w, int comp,
const nmv_component* mvcomp, int usehp) {
int offset;
const int sign = comp < 0;
const int mag = sign ? -comp : comp;
const int mv_class = vp9_get_mv_class(mag - 1, &offset);
const int d = offset >> 3; // int mv data
const int fr = (offset >> 1) & 3; // fractional mv data
const int hp = offset & 1; // high precision mv data
assert(comp != 0);
// Sign
vp9_write(w, sign, mvcomp->sign);
// Class
vp9_write_token(w, vp9_mv_class_tree, mvcomp->classes,
&mv_class_encodings[mv_class]);
// Integer bits
if (mv_class == MV_CLASS_0) {
vp9_write_token(w, vp9_mv_class0_tree, mvcomp->class0,
&mv_class0_encodings[d]);
} else {
int i;
const int n = mv_class + CLASS0_BITS - 1; // number of bits
for (i = 0; i < n; ++i)
vp9_write(w, (d >> i) & 1, mvcomp->bits[i]);
}
// Fractional bits
vp9_write_token(w, vp9_mv_fp_tree,
mv_class == MV_CLASS_0 ? mvcomp->class0_fp[d] : mvcomp->fp,
&mv_fp_encodings[fr]);
// High precision bit
if (usehp)
vp9_write(w, hp,
mv_class == MV_CLASS_0 ? mvcomp->class0_hp : mvcomp->hp);
}
static void build_nmv_component_cost_table(int *mvcost,
const nmv_component* const mvcomp,
int usehp) {
int i, v;
int sign_cost[2], class_cost[MV_CLASSES], class0_cost[CLASS0_SIZE];
int bits_cost[MV_OFFSET_BITS][2];
int class0_fp_cost[CLASS0_SIZE][MV_FP_SIZE], fp_cost[MV_FP_SIZE];
int class0_hp_cost[2], hp_cost[2];
sign_cost[0] = vp9_cost_zero(mvcomp->sign);
sign_cost[1] = vp9_cost_one(mvcomp->sign);
vp9_cost_tokens(class_cost, mvcomp->classes, vp9_mv_class_tree);
vp9_cost_tokens(class0_cost, mvcomp->class0, vp9_mv_class0_tree);
for (i = 0; i < MV_OFFSET_BITS; ++i) {
bits_cost[i][0] = vp9_cost_zero(mvcomp->bits[i]);
bits_cost[i][1] = vp9_cost_one(mvcomp->bits[i]);
}
for (i = 0; i < CLASS0_SIZE; ++i)
vp9_cost_tokens(class0_fp_cost[i], mvcomp->class0_fp[i], vp9_mv_fp_tree);
vp9_cost_tokens(fp_cost, mvcomp->fp, vp9_mv_fp_tree);
if (usehp) {
class0_hp_cost[0] = vp9_cost_zero(mvcomp->class0_hp);
class0_hp_cost[1] = vp9_cost_one(mvcomp->class0_hp);
hp_cost[0] = vp9_cost_zero(mvcomp->hp);
hp_cost[1] = vp9_cost_one(mvcomp->hp);
}
mvcost[0] = 0;
for (v = 1; v <= MV_MAX; ++v) {
int z, c, o, d, e, f, cost = 0;
z = v - 1;
c = vp9_get_mv_class(z, &o);
cost += class_cost[c];
d = (o >> 3); /* int mv data */
f = (o >> 1) & 3; /* fractional pel mv data */
e = (o & 1); /* high precision mv data */
if (c == MV_CLASS_0) {
cost += class0_cost[d];
} else {
int i, b;
b = c + CLASS0_BITS - 1; /* number of bits */
for (i = 0; i < b; ++i)
cost += bits_cost[i][((d >> i) & 1)];
}
if (c == MV_CLASS_0) {
cost += class0_fp_cost[d][f];
} else {
cost += fp_cost[f];
}
if (usehp) {
if (c == MV_CLASS_0) {
cost += class0_hp_cost[e];
} else {
cost += hp_cost[e];
}
}
mvcost[v] = cost + sign_cost[0];
mvcost[-v] = cost + sign_cost[1];
}
}
static int update_mv(vp9_writer *w, const unsigned int ct[2], vp9_prob *cur_p,
vp9_prob upd_p) {
const vp9_prob new_p = get_binary_prob(ct[0], ct[1]) | 1;
const int update = cost_branch256(ct, *cur_p) + vp9_cost_zero(upd_p) >
cost_branch256(ct, new_p) + vp9_cost_one(upd_p) + 7 * 256;
vp9_write(w, update, upd_p);
if (update) {
*cur_p = new_p;
vp9_write_literal(w, new_p >> 1, 7);
}
return update;
}
static void write_mv_update(const vp9_tree_index *tree,
vp9_prob probs[/*n - 1*/],
const unsigned int counts[/*n - 1*/],
int n, vp9_writer *w) {
int i;
unsigned int branch_ct[32][2];
// Assuming max number of probabilities <= 32
assert(n <= 32);
vp9_tree_probs_from_distribution(tree, branch_ct, counts);
for (i = 0; i < n - 1; ++i)
update_mv(w, branch_ct[i], &probs[i], MV_UPDATE_PROB);
}
void vp9_write_nmv_probs(VP9_COMMON *cm, int usehp, vp9_writer *w) {
int i, j;
nmv_context *const mvc = &cm->fc.nmvc;
nmv_context_counts *const counts = &cm->counts.mv;
write_mv_update(vp9_mv_joint_tree, mvc->joints, counts->joints, MV_JOINTS, w);
for (i = 0; i < 2; ++i) {
nmv_component *comp = &mvc->comps[i];
nmv_component_counts *comp_counts = &counts->comps[i];
update_mv(w, comp_counts->sign, &comp->sign, MV_UPDATE_PROB);
write_mv_update(vp9_mv_class_tree, comp->classes, comp_counts->classes,
MV_CLASSES, w);
write_mv_update(vp9_mv_class0_tree, comp->class0, comp_counts->class0,
CLASS0_SIZE, w);
for (j = 0; j < MV_OFFSET_BITS; ++j)
update_mv(w, comp_counts->bits[j], &comp->bits[j], MV_UPDATE_PROB);
}
for (i = 0; i < 2; ++i) {
for (j = 0; j < CLASS0_SIZE; ++j)
write_mv_update(vp9_mv_fp_tree, mvc->comps[i].class0_fp[j],
counts->comps[i].class0_fp[j], MV_FP_SIZE, w);
write_mv_update(vp9_mv_fp_tree, mvc->comps[i].fp, counts->comps[i].fp,
MV_FP_SIZE, w);
}
if (usehp) {
for (i = 0; i < 2; ++i) {
update_mv(w, counts->comps[i].class0_hp, &mvc->comps[i].class0_hp,
MV_UPDATE_PROB);
update_mv(w, counts->comps[i].hp, &mvc->comps[i].hp, MV_UPDATE_PROB);
}
}
}
void vp9_encode_mv(VP9_COMP* cpi, vp9_writer* w,
const MV* mv, const MV* ref,
const nmv_context* mvctx, int usehp) {
const MV diff = {mv->row - ref->row,
mv->col - ref->col};
const MV_JOINT_TYPE j = vp9_get_mv_joint(&diff);
usehp = usehp && vp9_use_mv_hp(ref);
vp9_write_token(w, vp9_mv_joint_tree, mvctx->joints, &mv_joint_encodings[j]);
if (mv_joint_vertical(j))
encode_mv_component(w, diff.row, &mvctx->comps[0], usehp);
if (mv_joint_horizontal(j))
encode_mv_component(w, diff.col, &mvctx->comps[1], usehp);
// If auto_mv_step_size is enabled then keep track of the largest
// motion vector component used.
if (cpi->sf.mv.auto_mv_step_size) {
unsigned int maxv = MAX(abs(mv->row), abs(mv->col)) >> 3;
cpi->max_mv_magnitude = MAX(maxv, cpi->max_mv_magnitude);
}
}
void vp9_build_nmv_cost_table(int *mvjoint, int *mvcost[2],
const nmv_context* ctx, int usehp) {
vp9_cost_tokens(mvjoint, ctx->joints, vp9_mv_joint_tree);
build_nmv_component_cost_table(mvcost[0], &ctx->comps[0], usehp);
build_nmv_component_cost_table(mvcost[1], &ctx->comps[1], usehp);
}
static void inc_mvs(const MB_MODE_INFO *mbmi, const int_mv mvs[2],
nmv_context_counts *counts) {
int i;
for (i = 0; i < 1 + has_second_ref(mbmi); ++i) {
const MV *ref = &mbmi->ref_mvs[mbmi->ref_frame[i]][0].as_mv;
const MV diff = {mvs[i].as_mv.row - ref->row,
mvs[i].as_mv.col - ref->col};
vp9_inc_mv(&diff, counts);
}
}
void vp9_update_mv_count(VP9_COMMON *cm, const MACROBLOCKD *xd) {
const MODE_INFO *mi = xd->mi[0].src_mi;
const MB_MODE_INFO *const mbmi = &mi->mbmi;
if (mbmi->sb_type < BLOCK_8X8) {
const int num_4x4_w = num_4x4_blocks_wide_lookup[mbmi->sb_type];
const int num_4x4_h = num_4x4_blocks_high_lookup[mbmi->sb_type];
int idx, idy;
for (idy = 0; idy < 2; idy += num_4x4_h) {
for (idx = 0; idx < 2; idx += num_4x4_w) {
const int i = idy * 2 + idx;
if (mi->bmi[i].as_mode == NEWMV)
inc_mvs(mbmi, mi->bmi[i].as_mv, &cm->counts.mv);
}
}
} else {
if (mbmi->mode == NEWMV)
inc_mvs(mbmi, mbmi->mv, &cm->counts.mv);
}
}