uvg266/src/rdo.c

701 lines
28 KiB
C

/*****************************************************************************
* This file is part of Kvazaar HEVC encoder.
*
* Copyright (C) 2013-2014 Tampere University of Technology and others (see
* COPYING file).
*
* Kvazaar is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation.
*
* Kvazaar is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with Kvazaar. If not, see <http://www.gnu.org/licenses/>.
****************************************************************************/
/*
* \file
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "rdo.h"
#include "transform.h"
#include "context.h"
#include "cabac.h"
#define QUANT_SHIFT 14
#define MAX_TR_DYNAMIC_RANGE 15
#define SCAN_SET_SIZE 16
#define LOG2_SCAN_SET_SIZE 4
#define SBH_THRESHOLD 4
const uint32_t g_go_rice_range[5] = { 7, 14, 26, 46, 78 };
const uint32_t g_go_rice_prefix_len[5] = { 8, 7, 6, 5, 4 };
#define CTX_ENTROPY_BITS(ctx,val) entropy_bits[(ctx)->uc_state ^ val]
/**
* Entropy bits to estimate coded bits in RDO / RDOQ (From HM 12.0)
*/
const uint32_t entropy_bits[128] =
{
0x08000, 0x08000, 0x076da, 0x089a0, 0x06e92, 0x09340, 0x0670a, 0x09cdf, 0x06029, 0x0a67f, 0x059dd, 0x0b01f, 0x05413, 0x0b9bf, 0x04ebf, 0x0c35f,
0x049d3, 0x0ccff, 0x04546, 0x0d69e, 0x0410d, 0x0e03e, 0x03d22, 0x0e9de, 0x0397d, 0x0f37e, 0x03619, 0x0fd1e, 0x032ee, 0x106be, 0x02ffa, 0x1105d,
0x02d37, 0x119fd, 0x02aa2, 0x1239d, 0x02836, 0x12d3d, 0x025f2, 0x136dd, 0x023d1, 0x1407c, 0x021d2, 0x14a1c, 0x01ff2, 0x153bc, 0x01e2f, 0x15d5c,
0x01c87, 0x166fc, 0x01af7, 0x1709b, 0x0197f, 0x17a3b, 0x0181d, 0x183db, 0x016d0, 0x18d7b, 0x01595, 0x1971b, 0x0146c, 0x1a0bb, 0x01354, 0x1aa5a,
0x0124c, 0x1b3fa, 0x01153, 0x1bd9a, 0x01067, 0x1c73a, 0x00f89, 0x1d0da, 0x00eb7, 0x1da79, 0x00df0, 0x1e419, 0x00d34, 0x1edb9, 0x00c82, 0x1f759,
0x00bda, 0x200f9, 0x00b3c, 0x20a99, 0x00aa5, 0x21438, 0x00a17, 0x21dd8, 0x00990, 0x22778, 0x00911, 0x23118, 0x00898, 0x23ab8, 0x00826, 0x24458,
0x007ba, 0x24df7, 0x00753, 0x25797, 0x006f2, 0x26137, 0x00696, 0x26ad7, 0x0063f, 0x27477, 0x005ed, 0x27e17, 0x0059f, 0x287b6, 0x00554, 0x29156,
0x0050e, 0x29af6, 0x004cc, 0x2a497, 0x0048d, 0x2ae35, 0x00451, 0x2b7d6, 0x00418, 0x2c176, 0x003e2, 0x2cb15, 0x003af, 0x2d4b5, 0x0037f, 0x2de55
};
#define COEF_REMAIN_BIN_REDUCTION 3
/** Calculates the cost for specific absolute transform level
* \param abs_level scaled quantized level
* \param ctx_num_one current ctxInc for coeff_abs_level_greater1 (1st bin of coeff_abs_level_minus1 in AVC)
* \param ctx_num_abs current ctxInc for coeff_abs_level_greater2 (remaining bins of coeff_abs_level_minus1 in AVC)
* \param abs_go_rice Rice parameter for coeff_abs_level_minus3
* \returns cost of given absolute transform level
* From HM 12.0
*/
double get_ic_rate_cost (uint32_t abs_level,
uint16_t ctx_num_one,
uint16_t ctx_num_abs,
uint16_t abs_go_rice,
uint32_t c1_idx,
uint32_t c2_idx,
int8_t type
)
{
double rate = 32768.0;
uint32_t base_level = (c1_idx < C1FLAG_NUMBER)? (2 + (c2_idx < C2FLAG_NUMBER)) : 1;
cabac_ctx *base_one_ctx = (type == 0) ? &g_cu_one_model_luma[0] : &g_cu_one_model_chroma[0];
cabac_ctx *base_abs_ctx = (type == 0) ? &g_cu_abs_model_luma[0] : &g_cu_abs_model_chroma[0];
if ( abs_level >= base_level ) {
int32_t symbol = abs_level - base_level;
int32_t length;
if (symbol < (COEF_REMAIN_BIN_REDUCTION << abs_go_rice)) {
length = symbol>>abs_go_rice;
rate += (length+1+abs_go_rice)<< 15;
} else {
length = abs_go_rice;
symbol = symbol - ( COEF_REMAIN_BIN_REDUCTION << abs_go_rice);
while (symbol >= (1<<length)) {
symbol -= (1<<(length++));
}
rate += (COEF_REMAIN_BIN_REDUCTION+length+1-abs_go_rice+length)<< 15;
}
if (c1_idx < C1FLAG_NUMBER) {
rate += CTX_ENTROPY_BITS(&base_one_ctx[ctx_num_one],1);
if (c2_idx < C2FLAG_NUMBER) {
rate += CTX_ENTROPY_BITS(&base_abs_ctx[ctx_num_abs],1);
}
}
}
else if( abs_level == 1 ) {
rate += CTX_ENTROPY_BITS(&base_one_ctx[ctx_num_one],0);
} else if( abs_level == 2 ) {
rate += CTX_ENTROPY_BITS(&base_one_ctx[ctx_num_one],1);
rate += CTX_ENTROPY_BITS(&base_abs_ctx[ctx_num_abs],0);
}
return rate;
}
int32_t get_ic_rate( uint32_t abs_level, uint16_t ctx_num_one,uint16_t ctx_num_abs,
uint16_t abs_go_rice, uint32_t c1_idx, uint32_t c2_idx, int8_t type)
{
int32_t rate = 0;
uint32_t base_level = (c1_idx < C1FLAG_NUMBER)? (2 + (c2_idx < C2FLAG_NUMBER)) : 1;
cabac_ctx *base_one_ctx = (type == 0) ? &g_cu_one_model_luma[0] : &g_cu_one_model_chroma[0];
cabac_ctx *base_abs_ctx = (type == 0) ? &g_cu_abs_model_luma[0] : &g_cu_abs_model_chroma[0];
if(!abs_level) return 0;
if (abs_level >= base_level) {
uint32_t symbol = abs_level - base_level;
uint32_t max_vlc = g_go_rice_range[ abs_go_rice ];
uint16_t pref_len,num_bins;
if (symbol > max_vlc) { //Exp. Golomb
int32_t iEGS = 1;
uint32_t uiMax = 2;
abs_level = symbol - max_vlc;
for(; abs_level >= uiMax; uiMax <<= 1, iEGS += 2 );
rate += iEGS << 15;
symbol = MIN( symbol, ( max_vlc + 1 ) );
}
pref_len = (uint16_t)(symbol >> abs_go_rice) + 1;
num_bins = (uint16_t)MIN( pref_len, g_go_rice_prefix_len[ abs_go_rice ] ) + abs_go_rice;
rate += num_bins << 15;
if (c1_idx < C1FLAG_NUMBER) {
rate += CTX_ENTROPY_BITS(&base_one_ctx[ctx_num_one],1);
if (c2_idx < C2FLAG_NUMBER) {
rate += CTX_ENTROPY_BITS(&base_abs_ctx[ctx_num_abs],1);
}
}
} else if( abs_level == 1 ) {
rate += CTX_ENTROPY_BITS(&base_one_ctx[ctx_num_one],0);
} else if( abs_level == 2 ) {
rate += CTX_ENTROPY_BITS(&base_one_ctx[ctx_num_one],1);
rate += CTX_ENTROPY_BITS(&base_abs_ctx[ctx_num_abs],0);
}
return rate;
}
/** Get the best level in RD sense
* \param coded_cost reference to coded cost
* \param coded_cost0 reference to cost when coefficient is 0
* \param coded_cost_sig reference to cost of significant coefficient
* \param level_double reference to unscaled quantized level
* \param max_abs_level scaled quantized level
* \param ctx_num_sig current ctxInc for coeff_abs_significant_flag
* \param ctx_num_one current ctxInc for coeff_abs_level_greater1 (1st bin of coeff_abs_level_minus1 in AVC)
* \param ctx_num_abs current ctxInc for coeff_abs_level_greater2 (remaining bins of coeff_abs_level_minus1 in AVC)
* \param abs_go_rice current Rice parameter for coeff_abs_level_minus3
* \param q_bits quantization step size
* \param temp correction factor
* \param last indicates if the coefficient is the last significant
* \returns best quantized transform level for given scan position
* This method calculates the best quantized transform level for a given scan position.
* From HM 12.0
*/
uint32_t get_coded_level ( encoder_control* encoder, double *coded_cost, double *coded_cost0, double *coded_cost_sig,
int32_t level_double, uint32_t max_abs_level,
uint16_t ctx_num_sig, uint16_t ctx_num_one, uint16_t ctx_num_abs,
uint16_t abs_go_rice,
uint32_t c1_idx, uint32_t c2_idx,
int32_t q_bits,double temp, int8_t last, int8_t type)
{
double cur_cost_sig = 0;
uint32_t best_abs_level = 0;
int32_t abs_level;
int32_t min_abs_level;
cabac_ctx* base_sig_model = type?g_cu_sig_model_chroma:g_cu_sig_model_luma;
if( !last && max_abs_level < 3 ) {
*coded_cost_sig = g_lambda_cost[encoder->QP] * CTX_ENTROPY_BITS(&base_sig_model[ctx_num_sig], 0);
*coded_cost = *coded_cost0 + *coded_cost_sig;
if (max_abs_level == 0) return best_abs_level;
} else {
*coded_cost = MAX_DOUBLE;
}
if( !last ) {
cur_cost_sig = g_lambda_cost[encoder->QP] * CTX_ENTROPY_BITS(&base_sig_model[ctx_num_sig], 1);
}
min_abs_level = ( max_abs_level > 1 ? max_abs_level - 1 : 1 );
for (abs_level = max_abs_level; abs_level >= min_abs_level ; abs_level-- ) {
double err = (double)(level_double - ( abs_level << q_bits ) );
double cur_cost = err * err * temp + g_lambda_cost[encoder->QP] *
get_ic_rate_cost( abs_level, ctx_num_one, ctx_num_abs,
abs_go_rice, c1_idx, c2_idx, type);
cur_cost += cur_cost_sig;
if( cur_cost < *coded_cost ) {
best_abs_level = abs_level;
*coded_cost = cur_cost;
*coded_cost_sig = cur_cost_sig;
}
}
return best_abs_level;
}
/** Calculates the cost of signaling the last significant coefficient in the block
* \param pos_x X coordinate of the last significant coefficient
* \param pos_y Y coordinate of the last significant coefficient
* \returns cost of last significant coefficient
* \param uiWidth width of the transform unit (TU)
*
* From HM 12.0
*/
double get_rate_last(encoder_control* encoder, const uint32_t pos_x, const uint32_t pos_y, int32_t* last_x_bits, int32_t* last_y_bits)
{
uint32_t ctx_x = g_group_idx[pos_x];
uint32_t ctx_y = g_group_idx[pos_y];
double uiCost = last_x_bits[ ctx_x ] + last_y_bits[ ctx_y ];
if( ctx_x > 3 ) {
uiCost += 32768.0 * ((ctx_x-2)>>1);
}
if( ctx_y > 3 ) {
uiCost += 32768.0 * ((ctx_y-2)>>1);
}
return g_lambda_cost[encoder->QP]*uiCost;
}
void calc_last_bits(int32_t width, int32_t height, int8_t type, int32_t* last_x_bits, int32_t* last_y_bits)
{
int32_t bits_x = 0, bits_y = 0;
int32_t blk_size_offset_x, blk_size_offset_y, shiftX, shiftY;
int32_t ctx;
cabac_ctx *base_ctx_x = (type ? g_cu_ctx_last_x_chroma : g_cu_ctx_last_x_luma);
cabac_ctx *base_ctx_y = (type ? g_cu_ctx_last_y_chroma : g_cu_ctx_last_y_luma);
blk_size_offset_x = type ? 0: (g_convert_to_bit[ width ] *3 + ((g_convert_to_bit[ width ] +1)>>2));
blk_size_offset_y = type ? 0: (g_convert_to_bit[ height ]*3 + ((g_convert_to_bit[ height ]+1)>>2));
shiftX = type ? g_convert_to_bit[ width ] :((g_convert_to_bit[ width ]+3)>>2);
shiftY = type ? g_convert_to_bit[ height ] :((g_convert_to_bit[ height ]+3)>>2);
for (ctx = 0; ctx < g_group_idx[ width - 1 ]; ctx++) {
int32_t ctx_offset = blk_size_offset_x + (ctx >>shiftX);
last_x_bits[ ctx ] = bits_x + CTX_ENTROPY_BITS(&base_ctx_x[ ctx_offset ],0);
bits_x += CTX_ENTROPY_BITS(&base_ctx_x[ ctx_offset ],1);
}
last_x_bits[ctx] = bits_x;
for (ctx = 0; ctx < g_group_idx[ height - 1 ]; ctx++) {
int32_t ctx_offset = blk_size_offset_y + (ctx >>shiftY);
last_y_bits[ ctx ] = bits_y + CTX_ENTROPY_BITS(&base_ctx_y[ ctx_offset ],0);
bits_y += CTX_ENTROPY_BITS(&base_ctx_y[ ctx_offset ],1);
}
last_y_bits[ctx] = bits_y;
}
/** RDOQ with CABAC
* \returns void
* Rate distortion optimized quantization for entropy
* coding engines using probability models like CABAC
* From HM 12.0
*/
void rdoq(encoder_control *encoder, coefficient *coef, coefficient *dest_coeff, int32_t width,
int32_t height, uint32_t *abs_sum, int8_t type, int8_t scan_mode, int8_t block_type, int8_t tr_depth)
{
uint32_t log2_tr_size = g_convert_to_bit[ width ] + 2;
int32_t transform_shift = MAX_TR_DYNAMIC_RANGE - g_bitdepth - log2_tr_size; // Represents scaling through forward transform
uint16_t go_rice_param = 0;
uint32_t log2_block_size = g_convert_to_bit[ width ] + 2;
uint32_t max_num_coeff = width * height;
int32_t scalinglist_type= (block_type == CU_INTRA ? 0 : 3) + (int8_t)("\0\3\1\2"[type]);
int32_t qp_base = encoder->QP;
int32_t qp_scaled = get_scaled_qp(type, encoder->QP, 0);
{
int32_t q_bits = QUANT_SHIFT + qp_scaled/6 + transform_shift;
int32_t *quant_coeff = g_quant_coeff[log2_tr_size-2][scalinglist_type][qp_scaled%6];
double *err_scale = g_error_scale[log2_tr_size-2][scalinglist_type][qp_scaled%6];
double block_uncoded_cost = 0;
double cost_coeff [ 32 * 32 ];
double cost_sig [ 32 * 32 ];
double cost_coeff0[ 32 * 32 ];
int32_t rate_inc_up [ 32 * 32 ];
int32_t rate_inc_down [ 32 * 32 ];
int32_t sig_rate_delta[ 32 * 32 ];
int32_t delta_u [ 32 * 32 ];
const uint32_t *scan_cg = NULL;
const int32_t shift = 4>>1;
const uint32_t cg_size = 16;
const uint32_t num_blk_side = width >> shift;
double cost_coeffgroup_sig[ 64 ];
uint32_t sig_coeffgroup_flag[ 64 ];
int32_t cg_last_scanpos = -1;
uint16_t ctx_set = 0;
int16_t c1 = 1;
int16_t c2 = 0;
double base_cost = 0;
int32_t last_scanpos = -1;
uint32_t c1_idx = 0;
uint32_t c2_idx = 0;
int32_t base_level;
uint32_t *scan = g_sig_last_scan[ scan_mode ][ log2_block_size - 1 ];
uint32_t cg_num = width * height >> 4;
int32_t scanpos;
cabac_ctx *base_coeff_group_ctx = &g_cu_sig_coeff_group_model[type];
cabac_ctx *baseCtx = (type == 0) ? &g_cu_sig_model_luma[0] : &g_cu_sig_model_chroma[0];
cabac_ctx *base_one_ctx = (type == 0) ? &g_cu_one_model_luma[0] : &g_cu_one_model_chroma[0];
double best_cost = 0;
int32_t ctx_cbf = 0;
int32_t best_last_idx_p1 = 0;
int8_t found_last = 0;
int32_t cg_scanpos, scanpos_in_cg;
coeffgroup_rd_stats rd_stats;
int32_t last_x_bits[32],last_y_bits[32];
calc_last_bits(width, height, type,last_x_bits, last_y_bits);
memset( cost_coeff, 0, sizeof(double) * max_num_coeff );
memset( cost_sig, 0, sizeof(double) * max_num_coeff );
memset( rate_inc_up, 0, sizeof(int32_t) * max_num_coeff );
memset( rate_inc_down, 0, sizeof(int32_t) * max_num_coeff );
memset( sig_rate_delta, 0, sizeof(int32_t) * max_num_coeff );
memset( delta_u, 0, sizeof(int32_t) * max_num_coeff );
memset( cost_coeffgroup_sig, 0, sizeof(double) * 64 );
memset( sig_coeffgroup_flag, 0, sizeof(uint32_t) * 64 );
scan_cg = g_sig_last_scan[scan_mode][log2_block_size > 3 ? log2_block_size - 3 : 0];
if (log2_block_size == 3) {
scan_cg = g_sig_last_scan_8x8[scan_mode];
} else if (log2_block_size == 5) {
scan_cg = g_sig_last_scan_32x32;
}
for (cg_scanpos = cg_num-1; cg_scanpos >= 0; cg_scanpos--) {
uint32_t cg_blkpos = scan_cg[ cg_scanpos ];
uint32_t cg_pos_y = cg_blkpos / num_blk_side;
uint32_t cg_pos_x = cg_blkpos - (cg_pos_y * num_blk_side);
int32_t scanpos_in_cg;
int32_t pattern_sig_ctx = context_calc_pattern_sig_ctx(sig_coeffgroup_flag,
cg_pos_x, cg_pos_y, width);
memset( &rd_stats, 0, sizeof (coeffgroup_rd_stats));
for (scanpos_in_cg = cg_size-1; scanpos_in_cg >= 0; scanpos_in_cg--) {
uint32_t blkpos;
int32_t q;
double temp, err;
int32_t level_double;
uint32_t max_abs_level;
scanpos = cg_scanpos*cg_size + scanpos_in_cg;
blkpos = scan[scanpos];
q = quant_coeff[blkpos];
temp = err_scale[blkpos];
level_double = coef[blkpos];
level_double = MIN(abs(level_double) * q , MAX_INT - (1 << (q_bits - 1)));
max_abs_level = (level_double + (1 << (q_bits - 1))) >> q_bits;
err = (double)level_double;
cost_coeff0[ scanpos ] = err * err * temp;
block_uncoded_cost += cost_coeff0[ scanpos ];
dest_coeff[ blkpos ] = (coefficient)max_abs_level;
if ( max_abs_level > 0 && last_scanpos < 0 ) {
last_scanpos = scanpos;
ctx_set = (scanpos > 0 && type == 0) ? 2 : 0;
cg_last_scanpos = cg_scanpos;
}
if ( last_scanpos >= 0 ) {
//===== coefficient level estimation =====
int32_t level;
uint16_t one_ctx = 4 * ctx_set + c1;
uint16_t abs_ctx = ctx_set + c2;
if( scanpos == last_scanpos ) {
level = get_coded_level(encoder, &cost_coeff[ scanpos ], &cost_coeff0[ scanpos ], &cost_sig[ scanpos ],
level_double, max_abs_level, 0, one_ctx, abs_ctx, go_rice_param,
c1_idx, c2_idx, q_bits, temp, 1, type );
} else {
uint32_t pos_y = blkpos >> log2_block_size;
uint32_t pos_x = blkpos - ( pos_y << log2_block_size );
uint16_t ctx_sig = (uint16_t)context_get_sig_ctx_inc(pattern_sig_ctx, scan_mode, pos_x, pos_y,
log2_block_size, width, type);
level = get_coded_level(encoder, &cost_coeff[ scanpos ], &cost_coeff0[ scanpos ], &cost_sig[ scanpos ],
level_double, max_abs_level, ctx_sig, one_ctx, abs_ctx, go_rice_param,
c1_idx, c2_idx, q_bits, temp, 0, type );
sig_rate_delta[ blkpos ] = CTX_ENTROPY_BITS(&baseCtx[ctx_sig],1) - CTX_ENTROPY_BITS(&baseCtx[ctx_sig],0);
}
delta_u[ blkpos ] = (level_double - ((int32_t)level << q_bits)) >> (q_bits-8);
if( level > 0 ) {
int32_t rate_now = get_ic_rate( level, one_ctx, abs_ctx, go_rice_param, c1_idx, c2_idx, type);
rate_inc_up [blkpos] = get_ic_rate( level+1, one_ctx, abs_ctx, go_rice_param, c1_idx, c2_idx, type) - rate_now;
rate_inc_down[blkpos] = get_ic_rate( level-1, one_ctx, abs_ctx, go_rice_param, c1_idx, c2_idx, type) - rate_now;
} else { // level == 0
rate_inc_up[blkpos] = CTX_ENTROPY_BITS(&base_one_ctx[one_ctx],0);
}
dest_coeff[blkpos] = (coefficient)level;
base_cost += cost_coeff[scanpos];
base_level = (c1_idx < C1FLAG_NUMBER) ? (2 + (c2_idx < C2FLAG_NUMBER)) : 1;
if( level >= base_level ) {
if(level > 3*(1<<go_rice_param)) {
go_rice_param = MIN(go_rice_param + 1, 4);
}
}
if (level >= 1) c1_idx ++;
//===== update bin model =====
if (level > 1) {
c1 = 0;
c2 += (c2 < 2);
c2_idx ++;
} else if( (c1 < 3) && (c1 > 0) && level) {
c1++;
}
//===== context set update =====
if ((scanpos % SCAN_SET_SIZE == 0) && scanpos > 0) {
c2 = 0;
go_rice_param = 0;
c1_idx = 0;
c2_idx = 0;
ctx_set = (scanpos == SCAN_SET_SIZE || type!=0) ? 0 : 2;
if( c1 == 0 ) {
ctx_set++;
}
c1 = 1;
}
} else {
base_cost += cost_coeff0[scanpos];
}
rd_stats.sig_cost += cost_sig[scanpos];
if (scanpos_in_cg == 0 ) {
rd_stats.sig_cost_0 = cost_sig[scanpos];
}
if (dest_coeff[ blkpos ] ) {
sig_coeffgroup_flag[ cg_blkpos ] = 1;
rd_stats.coded_level_and_dist += cost_coeff[scanpos] - cost_sig[scanpos];
rd_stats.uncoded_dist += cost_coeff0[scanpos];
if ( scanpos_in_cg != 0 ) {
rd_stats.nnz_before_pos0++;
}
}
} //end for (scanpos_in_cg)
if (cg_last_scanpos >= 0) {
if( cg_scanpos ) {
if (sig_coeffgroup_flag[ cg_blkpos ] == 0) {
uint32_t ctx_sig = context_get_sig_coeff_group(sig_coeffgroup_flag, cg_pos_x,
cg_pos_y, width);
cost_coeffgroup_sig[ cg_scanpos ] = g_lambda_cost[encoder->QP]*CTX_ENTROPY_BITS(&base_coeff_group_ctx[ctx_sig],0);
base_cost += cost_coeffgroup_sig[ cg_scanpos ] - rd_stats.sig_cost;
} else {
if (cg_scanpos < cg_last_scanpos) {//skip the last coefficient group, which will be handled together with last position below.
double cost_zero_cg;
uint32_t ctx_sig;
if (rd_stats.nnz_before_pos0 == 0) {
base_cost -= rd_stats.sig_cost_0;
rd_stats.sig_cost -= rd_stats.sig_cost_0;
}
// rd-cost if SigCoeffGroupFlag = 0, initialization
cost_zero_cg = base_cost;
// add SigCoeffGroupFlag cost to total cost
ctx_sig = context_get_sig_coeff_group(sig_coeffgroup_flag, cg_pos_x,
cg_pos_y, width);
if (cg_scanpos < cg_last_scanpos) {
cost_coeffgroup_sig[cg_scanpos] = g_lambda_cost[encoder->QP]*CTX_ENTROPY_BITS(&base_coeff_group_ctx[ctx_sig],1);
base_cost += cost_coeffgroup_sig[cg_scanpos];
cost_zero_cg += g_lambda_cost[encoder->QP]*CTX_ENTROPY_BITS(&base_coeff_group_ctx[ctx_sig],0);
}
// try to convert the current coeff group from non-zero to all-zero
cost_zero_cg += rd_stats.uncoded_dist; // distortion for resetting non-zero levels to zero levels
cost_zero_cg -= rd_stats.coded_level_and_dist; // distortion and level cost for keeping all non-zero levels
cost_zero_cg -= rd_stats.sig_cost; // sig cost for all coeffs, including zero levels and non-zerl levels
// if we can save cost, change this block to all-zero block
if (cost_zero_cg < base_cost) {
int32_t scanpos_in_cg;
sig_coeffgroup_flag[ cg_blkpos ] = 0;
base_cost = cost_zero_cg;
if (cg_scanpos < cg_last_scanpos) {
cost_coeffgroup_sig[ cg_scanpos ] = g_lambda_cost[encoder->QP]*CTX_ENTROPY_BITS(&base_coeff_group_ctx[ctx_sig],0);
}
// reset coeffs to 0 in this block
for (scanpos_in_cg = cg_size-1; scanpos_in_cg >= 0; scanpos_in_cg--) {
uint32_t blkpos;
scanpos = cg_scanpos*cg_size + scanpos_in_cg;
blkpos = scan[ scanpos ];
if (dest_coeff[ blkpos ]) {
dest_coeff[ blkpos ] = 0;
cost_coeff[ scanpos ] = cost_coeff0[ scanpos ];
cost_sig [ scanpos ] = 0;
}
}
} // end if ( cost_all_zeros < base_cost )
}
} // end if if (sig_coeffgroup_flag[ cg_blkpos ] == 0)
} else {
sig_coeffgroup_flag[ cg_blkpos ] = 1;
}
}
} //end for (cg_scanpos)
//===== estimate last position =====
if (last_scanpos < 0) return;
if( block_type != CU_INTRA && !type/* && pcCU->getTransformIdx( uiAbsPartIdx ) == 0*/ ) {
best_cost = block_uncoded_cost + g_lambda_cost[encoder->QP]*CTX_ENTROPY_BITS(&g_cu_qt_root_cbf_model,0);
base_cost += g_lambda_cost[encoder->QP]*CTX_ENTROPY_BITS(&g_cu_qt_root_cbf_model,1);
} else {
cabac_ctx* base_cbf_model = type?g_qt_cbf_model_chroma:g_qt_cbf_model_luma;
ctx_cbf = ( type ? tr_depth : !tr_depth);
best_cost = block_uncoded_cost + g_lambda_cost[encoder->QP]*CTX_ENTROPY_BITS(&base_cbf_model[ctx_cbf],0);
base_cost += g_lambda_cost[encoder->QP]*CTX_ENTROPY_BITS(&base_cbf_model[ctx_cbf],1);
}
for (cg_scanpos = cg_last_scanpos; cg_scanpos >= 0; cg_scanpos--) {
uint32_t cg_blkpos = scan_cg[cg_scanpos];
base_cost -= cost_coeffgroup_sig[cg_scanpos];
if (sig_coeffgroup_flag[ cg_blkpos ]) {
for (scanpos_in_cg = cg_size-1; scanpos_in_cg >= 0; scanpos_in_cg--) {
uint32_t blkpos;
scanpos = cg_scanpos*cg_size + scanpos_in_cg;
if (scanpos > last_scanpos) continue;
blkpos = scan[scanpos];
if( dest_coeff[ blkpos ] ) {
uint32_t pos_y = blkpos >> log2_block_size;
uint32_t pos_x = blkpos - ( pos_y << log2_block_size );
double cost_last = (scan_mode == SCAN_VER) ? get_rate_last(encoder, pos_y, pos_x,last_x_bits,last_y_bits) : get_rate_last(encoder, pos_x, pos_y, last_x_bits,last_y_bits );
double totalCost = base_cost + cost_last - cost_sig[ scanpos ];
if( totalCost < best_cost ) {
best_last_idx_p1 = scanpos + 1;
best_cost = totalCost;
}
if( dest_coeff[ blkpos ] > 1 ) {
found_last = 1;
break;
}
base_cost -= cost_coeff[ scanpos ];
base_cost += cost_coeff0[ scanpos ];
} else {
base_cost -= cost_sig[ scanpos ];
}
} //end for
if (found_last) break;
} // end if (sig_coeffgroup_flag[ cg_blkpos ])
} // end for
for ( scanpos = 0; scanpos < best_last_idx_p1; scanpos++ ) {
int32_t blkPos = scan[ scanpos ];
int32_t level = dest_coeff[ blkPos ];
*abs_sum += level;
dest_coeff[ blkPos ] = (coefficient)(( coef[ blkPos ] < 0 ) ? -level : level);
}
//===== clean uncoded coefficients =====
for ( scanpos = best_last_idx_p1; scanpos <= last_scanpos; scanpos++ ) {
dest_coeff[ scan[ scanpos ] ] = 0;
}
#if ENABLE_SIGN_HIDING == 1
if(*abs_sum >= 2) {
int64_t rd_factor = (int64_t) (
g_inv_quant_scales[qp_scaled%6] * g_inv_quant_scales[qp_scaled%6] * (1<<(2*(qp_scaled/6)))
/ g_lambda_cost[encoder->QP] / 16 / (1<<(2*(g_bitdepth-8)))
+ 0.5);
int32_t lastCG = -1;
int32_t absSum = 0;
int32_t n,subset;
for (subset = (width*height-1) >> LOG2_SCAN_SET_SIZE; subset >= 0; subset--) {
int32_t subPos = subset << LOG2_SCAN_SET_SIZE;
int32_t firstNZPosInCG=SCAN_SET_SIZE, lastNZPosInCG = -1;
absSum = 0;
for(n = SCAN_SET_SIZE-1; n >= 0; --n ) {
if( dest_coeff[ scan[ n + subPos ]] ) {
lastNZPosInCG = n;
break;
}
}
for(n = 0; n <SCAN_SET_SIZE; n++ ) {
if( dest_coeff[ scan[ n + subPos ]] ) {
firstNZPosInCG = n;
break;
}
}
for(n = firstNZPosInCG; n <=lastNZPosInCG; n++ ) {
absSum += dest_coeff[ scan[ n + subPos ]];
}
if(lastNZPosInCG>=0 && lastCG==-1) lastCG = 1;
if (lastNZPosInCG-firstNZPosInCG >= SBH_THRESHOLD ) {
int32_t signbit = (dest_coeff[scan[subPos+firstNZPosInCG]]>0?0:1);
if( signbit!=(absSum&0x1) ) { // hide but need tune
// calculate the cost
int64_t minCostInc = MAX_INT64, curCost=MAX_INT64;
int32_t minPos =-1, finalChange=0, curChange=0;
for( n = (lastCG==1?lastNZPosInCG:SCAN_SET_SIZE-1) ; n >= 0; --n ) {
uint32_t blkpos = scan[ n + subPos ];
if(dest_coeff[ blkpos ] != 0 ) {
int64_t costUp = rd_factor * (-delta_u[blkpos]) + rate_inc_up[blkpos];
int64_t costDown = rd_factor * ( delta_u[blkpos]) + rate_inc_down[blkpos]
- ( abs(dest_coeff[blkpos])==1?((1<<15)+sig_rate_delta[blkpos]):0 );
if(lastCG==1 && lastNZPosInCG==n && abs(dest_coeff[blkpos])==1) {
costDown -= (4<<15);
}
if(costUp<costDown) {
curCost = costUp;
curChange = 1;
} else {
curChange = -1;
if(n==firstNZPosInCG && abs(dest_coeff[blkpos])==1) {
curCost = MAX_INT64;
} else {
curCost = costDown;
}
}
} else {
curCost = rd_factor * ( - (abs(delta_u[blkpos])) ) + (1<<15) + rate_inc_up[blkpos] + sig_rate_delta[blkpos];
curChange = 1;
if(n<firstNZPosInCG) {
if( ((coef[blkpos] >= 0) ? 0 : 1) != signbit ) curCost = MAX_INT64;
}
}
if( curCost<minCostInc) {
minCostInc = curCost;
finalChange = curChange;
minPos = blkpos;
}
}
if(dest_coeff[minPos] == 32767 || dest_coeff[minPos] == -32768) {
finalChange = -1;
}
if(coef[minPos]>=0) {
dest_coeff[minPos] += (coefficient)finalChange;
} else {
dest_coeff[minPos] -= (coefficient)finalChange;
}
}
}
if(lastCG==1) lastCG = 0;
}
}
#endif
}
}