Source code
Revision control
Copy as Markdown
Other Tools
/*
* Copyright (c) 2016, Alliance for Open Media. All rights reserved.
*
* This source code is subject to the terms of the BSD 2 Clause License and
* the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
* was not distributed with this source code in the LICENSE file, you can
* obtain it at www.aomedia.org/license/software. If the Alliance for Open
* Media Patent License 1.0 was not distributed with this source code in the
* PATENTS file, you can obtain it at www.aomedia.org/license/patent.
*/
#include <math.h>
#include "av1/common/common.h"
#include "av1/common/entropymode.h"
#include "av1/encoder/cost.h"
#include "av1/encoder/encodemv.h"
#include "aom_dsp/aom_dsp_common.h"
#include "aom_ports/bitops.h"
static void update_mv_component_stats(int comp, nmv_component *mvcomp,
MvSubpelPrecision precision) {
assert(comp != 0);
int offset;
const int sign = comp < 0;
const int mag = sign ? -comp : comp;
const int mv_class = av1_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
// Sign
update_cdf(mvcomp->sign_cdf, sign, 2);
// Class
update_cdf(mvcomp->classes_cdf, mv_class, MV_CLASSES);
// Integer bits
if (mv_class == MV_CLASS_0) {
update_cdf(mvcomp->class0_cdf, d, CLASS0_SIZE);
} else {
const int n = mv_class + CLASS0_BITS - 1; // number of bits
for (int i = 0; i < n; ++i)
update_cdf(mvcomp->bits_cdf[i], (d >> i) & 1, 2);
}
// Fractional bits
if (precision > MV_SUBPEL_NONE) {
aom_cdf_prob *fp_cdf =
mv_class == MV_CLASS_0 ? mvcomp->class0_fp_cdf[d] : mvcomp->fp_cdf;
update_cdf(fp_cdf, fr, MV_FP_SIZE);
}
// High precision bit
if (precision > MV_SUBPEL_LOW_PRECISION) {
aom_cdf_prob *hp_cdf =
mv_class == MV_CLASS_0 ? mvcomp->class0_hp_cdf : mvcomp->hp_cdf;
update_cdf(hp_cdf, hp, 2);
}
}
void av1_update_mv_stats(const MV *mv, const MV *ref, nmv_context *mvctx,
MvSubpelPrecision precision) {
const MV diff = { mv->row - ref->row, mv->col - ref->col };
const MV_JOINT_TYPE j = av1_get_mv_joint(&diff);
update_cdf(mvctx->joints_cdf, j, MV_JOINTS);
if (mv_joint_vertical(j))
update_mv_component_stats(diff.row, &mvctx->comps[0], precision);
if (mv_joint_horizontal(j))
update_mv_component_stats(diff.col, &mvctx->comps[1], precision);
}
static void encode_mv_component(aom_writer *w, int comp, nmv_component *mvcomp,
MvSubpelPrecision precision) {
assert(comp != 0);
int offset;
const int sign = comp < 0;
const int mag = sign ? -comp : comp;
const int mv_class = av1_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
// Sign
aom_write_symbol(w, sign, mvcomp->sign_cdf, 2);
// Class
aom_write_symbol(w, mv_class, mvcomp->classes_cdf, MV_CLASSES);
// Integer bits
if (mv_class == MV_CLASS_0) {
aom_write_symbol(w, d, mvcomp->class0_cdf, CLASS0_SIZE);
} else {
int i;
const int n = mv_class + CLASS0_BITS - 1; // number of bits
for (i = 0; i < n; ++i)
aom_write_symbol(w, (d >> i) & 1, mvcomp->bits_cdf[i], 2);
}
// Fractional bits
if (precision > MV_SUBPEL_NONE) {
aom_write_symbol(
w, fr,
mv_class == MV_CLASS_0 ? mvcomp->class0_fp_cdf[d] : mvcomp->fp_cdf,
MV_FP_SIZE);
}
// High precision bit
if (precision > MV_SUBPEL_LOW_PRECISION)
aom_write_symbol(
w, hp, mv_class == MV_CLASS_0 ? mvcomp->class0_hp_cdf : mvcomp->hp_cdf,
2);
}
/* TODO(siekyleb@amazon.com): This function writes MV_VALS ints or 128 KiB. This
* is more than most L1D caches and is a significant chunk of L2. Write
* SIMD that uses streaming writes to avoid loading all of that into L1, or
* just don't update the larger component costs every time this called
* (or both).
*/
void av1_build_nmv_component_cost_table(int *mvcost,
const nmv_component *const mvcomp,
MvSubpelPrecision precision) {
int i, j, v, o, mantissa;
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] = { 0 },
fp_cost[MV_FP_SIZE] = { 0 };
int class0_hp_cost[2] = { 0 }, hp_cost[2] = { 0 };
av1_cost_tokens_from_cdf(sign_cost, mvcomp->sign_cdf, NULL);
av1_cost_tokens_from_cdf(class_cost, mvcomp->classes_cdf, NULL);
av1_cost_tokens_from_cdf(class0_cost, mvcomp->class0_cdf, NULL);
for (i = 0; i < MV_OFFSET_BITS; ++i) {
av1_cost_tokens_from_cdf(bits_cost[i], mvcomp->bits_cdf[i], NULL);
}
if (precision > MV_SUBPEL_NONE) {
for (i = 0; i < CLASS0_SIZE; ++i)
av1_cost_tokens_from_cdf(class0_fp_cost[i], mvcomp->class0_fp_cdf[i],
NULL);
av1_cost_tokens_from_cdf(fp_cost, mvcomp->fp_cdf, NULL);
}
if (precision > MV_SUBPEL_LOW_PRECISION) {
av1_cost_tokens_from_cdf(class0_hp_cost, mvcomp->class0_hp_cdf, NULL);
av1_cost_tokens_from_cdf(hp_cost, mvcomp->hp_cdf, NULL);
}
// Instead of accumulating the cost of each vector component's bits
// individually, compute the costs based on smaller vectors. Costs for
// [2^exp, 2 * 2^exp - 1] are calculated based on [0, 2^exp - 1]
// respectively. Offsets are maintained to swap both 1) class costs when
// treated as a complete vector component with the highest set bit when
// treated as a mantissa (significand) and 2) leading zeros to account for
// the current exponent.
// Cost offsets
int cost_swap[MV_OFFSET_BITS] = { 0 };
// Delta to convert positive vector to negative vector costs
int negate_sign = sign_cost[1] - sign_cost[0];
// Initialize with offsets to swap the class costs with the costs of the
// highest set bit.
for (i = 1; i < MV_OFFSET_BITS; ++i) {
cost_swap[i] = bits_cost[i - 1][1];
if (i > CLASS0_BITS) cost_swap[i] -= class_cost[i - CLASS0_BITS];
}
// Seed the fractional costs onto the output (overwritten latter).
for (o = 0; o < MV_FP_SIZE; ++o) {
int hp;
for (hp = 0; hp < 2; ++hp) {
v = 2 * o + hp + 1;
mvcost[v] = fp_cost[o] + hp_cost[hp] + sign_cost[0];
}
}
mvcost[0] = 0;
// Fill the costs for each exponent's vectors, using the costs set in the
// previous exponents.
for (i = 0; i < MV_OFFSET_BITS; ++i) {
const int exponent = (2 * MV_FP_SIZE) << i;
int class = 0;
if (i >= CLASS0_BITS) {
class = class_cost[i - CLASS0_BITS + 1];
}
// Iterate through mantissas, keeping track of the location
// of the highest set bit for the mantissa.
// To be clear: in the outer loop, the position of the highest set bit
// (exponent) is tracked and, in this loop, the highest set bit of the
// mantissa is tracked.
mantissa = 0;
for (j = 0; j <= i; ++j) {
for (; mantissa < (2 * MV_FP_SIZE) << j; ++mantissa) {
int cost = mvcost[mantissa + 1] + class + cost_swap[j];
v = exponent + mantissa + 1;
mvcost[v] = cost;
mvcost[-v] = cost + negate_sign;
}
cost_swap[j] += bits_cost[i][0];
}
}
// Special case to avoid buffer overrun
{
int exponent = (2 * MV_FP_SIZE) << MV_OFFSET_BITS;
int class = class_cost[MV_CLASSES - 1];
mantissa = 0;
for (j = 0; j < MV_OFFSET_BITS; ++j) {
for (; mantissa < (2 * MV_FP_SIZE) << j; ++mantissa) {
int cost = mvcost[mantissa + 1] + class + cost_swap[j];
v = exponent + mantissa + 1;
mvcost[v] = cost;
mvcost[-v] = cost + negate_sign;
}
}
// At this point: mantissa = exponent >> 1
// Manually calculate the final cost offset
int cost_swap_hi =
bits_cost[MV_OFFSET_BITS - 1][1] - class_cost[MV_CLASSES - 2];
for (; mantissa < exponent - 1; ++mantissa) {
int cost = mvcost[mantissa + 1] + class + cost_swap_hi;
v = exponent + mantissa + 1;
mvcost[v] = cost;
mvcost[-v] = cost + negate_sign;
}
}
// Fill costs for class0 vectors, overwriting previous placeholder values
// used for calculating the costs of the larger vectors.
for (i = 0; i < CLASS0_SIZE; ++i) {
const int top = i * 2 * MV_FP_SIZE;
for (o = 0; o < MV_FP_SIZE; ++o) {
int hp;
int cost = class0_fp_cost[i][o] + class_cost[0] + class0_cost[i];
for (hp = 0; hp < 2; ++hp) {
v = top + 2 * o + hp + 1;
mvcost[v] = cost + class0_hp_cost[hp] + sign_cost[0];
mvcost[-v] = cost + class0_hp_cost[hp] + sign_cost[1];
}
}
}
}
void av1_encode_mv(AV1_COMP *cpi, aom_writer *w, ThreadData *td, const MV *mv,
const MV *ref, nmv_context *mvctx, int usehp) {
const MV diff = { mv->row - ref->row, mv->col - ref->col };
const MV_JOINT_TYPE j = av1_get_mv_joint(&diff);
// If the mv_diff is zero, then we should have used near or nearest instead.
assert(j != MV_JOINT_ZERO);
if (cpi->common.features.cur_frame_force_integer_mv) {
usehp = MV_SUBPEL_NONE;
}
aom_write_symbol(w, j, mvctx->joints_cdf, MV_JOINTS);
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_sf.auto_mv_step_size) {
int maxv = AOMMAX(abs(mv->row), abs(mv->col)) >> 3;
td->max_mv_magnitude = AOMMAX(maxv, td->max_mv_magnitude);
}
}
void av1_encode_dv(aom_writer *w, const MV *mv, const MV *ref,
nmv_context *mvctx) {
// DV and ref DV should not have sub-pel.
assert((mv->col & 7) == 0);
assert((mv->row & 7) == 0);
assert((ref->col & 7) == 0);
assert((ref->row & 7) == 0);
const MV diff = { mv->row - ref->row, mv->col - ref->col };
const MV_JOINT_TYPE j = av1_get_mv_joint(&diff);
aom_write_symbol(w, j, mvctx->joints_cdf, MV_JOINTS);
if (mv_joint_vertical(j))
encode_mv_component(w, diff.row, &mvctx->comps[0], MV_SUBPEL_NONE);
if (mv_joint_horizontal(j))
encode_mv_component(w, diff.col, &mvctx->comps[1], MV_SUBPEL_NONE);
}
void av1_build_nmv_cost_table(int *mvjoint, int *mvcost[2],
const nmv_context *ctx,
MvSubpelPrecision precision) {
av1_cost_tokens_from_cdf(mvjoint, ctx->joints_cdf, NULL);
av1_build_nmv_component_cost_table(mvcost[0], &ctx->comps[0], precision);
av1_build_nmv_component_cost_table(mvcost[1], &ctx->comps[1], precision);
}
int_mv av1_get_ref_mv_from_stack(int ref_idx,
const MV_REFERENCE_FRAME *ref_frame,
int ref_mv_idx,
const MB_MODE_INFO_EXT *mbmi_ext) {
const int8_t ref_frame_type = av1_ref_frame_type(ref_frame);
const CANDIDATE_MV *curr_ref_mv_stack =
mbmi_ext->ref_mv_stack[ref_frame_type];
if (ref_frame[1] > INTRA_FRAME) {
assert(ref_idx == 0 || ref_idx == 1);
return ref_idx ? curr_ref_mv_stack[ref_mv_idx].comp_mv
: curr_ref_mv_stack[ref_mv_idx].this_mv;
}
assert(ref_idx == 0);
return ref_mv_idx < mbmi_ext->ref_mv_count[ref_frame_type]
? curr_ref_mv_stack[ref_mv_idx].this_mv
: mbmi_ext->global_mvs[ref_frame_type];
}
int_mv av1_get_ref_mv(const MACROBLOCK *x, int ref_idx) {
const MACROBLOCKD *xd = &x->e_mbd;
const MB_MODE_INFO *mbmi = xd->mi[0];
int ref_mv_idx = mbmi->ref_mv_idx;
if (mbmi->mode == NEAR_NEWMV || mbmi->mode == NEW_NEARMV) {
assert(has_second_ref(mbmi));
ref_mv_idx += 1;
}
return av1_get_ref_mv_from_stack(ref_idx, mbmi->ref_frame, ref_mv_idx,
&x->mbmi_ext);
}
void av1_find_best_ref_mvs_from_stack(int allow_hp,
const MB_MODE_INFO_EXT *mbmi_ext,
MV_REFERENCE_FRAME ref_frame,
int_mv *nearest_mv, int_mv *near_mv,
int is_integer) {
const int ref_idx = 0;
MV_REFERENCE_FRAME ref_frames[2] = { ref_frame, NONE_FRAME };
*nearest_mv = av1_get_ref_mv_from_stack(ref_idx, ref_frames, 0, mbmi_ext);
lower_mv_precision(&nearest_mv->as_mv, allow_hp, is_integer);
*near_mv = av1_get_ref_mv_from_stack(ref_idx, ref_frames, 1, mbmi_ext);
lower_mv_precision(&near_mv->as_mv, allow_hp, is_integer);
}