/*****************************************************************************
* This file is part of Kvazaar HEVC encoder.
*
* Copyright (C) 2013-2015 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 Lesser General Public License as published by the
* Free Software Foundation; either version 2.1 of the License, or (at your
* option) any later version.
*
* 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 Lesser General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along
* with Kvazaar. If not, see .
****************************************************************************/
#include "strategyselector.h"
#include "cabac.h"
#include "context.h"
#include "encode_coding_tree-avx2.h"
#include "kvz_math.h"
#include
static INLINE __m256i scanord_read_vector(const int16_t *coeff, const uint32_t *scan, int8_t scan_mode, int32_t subpos, int32_t width)
{
// For vectorized reordering of coef and q_coef
const __m128i low128_shuffle_masks[3] = {
_mm_setr_epi8(10,11, 4, 5, 12,13, 0, 1, 6, 7, 14,15, 8, 9, 2, 3),
_mm_setr_epi8( 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10,11, 12,13, 14,15),
_mm_setr_epi8( 4, 5, 6, 7, 0, 1, 2, 3, 12,13, 14,15, 8, 9, 10,11),
};
const __m128i blend_masks[3] = {
_mm_setr_epi16( 0, 0, 0, -1, 0, 0, -1, -1),
_mm_setr_epi16( 0, 0, 0, 0, 0, 0, 0, 0),
_mm_setr_epi16( 0, 0, -1, -1, 0, 0, -1, -1),
};
const __m128i invec_rearr_masks_upper[3] = {
_mm_setr_epi8( 0, 1, 8, 9, 2, 3, 6, 7, 10,11, 4, 5, 12,13, 14,15),
_mm_setr_epi8( 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10,11, 12,13, 14,15),
_mm_setr_epi8( 0, 1, 8, 9, 4, 5, 12,13, 2, 3, 10,11, 6, 7, 14,15),
};
const __m128i invec_rearr_masks_lower[3] = {
_mm_setr_epi8(12,13, 6, 7, 0, 1, 2, 3, 14,15, 4, 5, 8, 9, 10,11),
_mm_setr_epi8( 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10,11, 12,13, 14,15),
_mm_setr_epi8( 4, 5, 12,13, 0, 1, 8, 9, 6, 7, 14,15, 2, 3, 10,11),
};
const size_t row_offsets[4] = {
scan[subpos] + width * 0,
scan[subpos] + width * 1,
scan[subpos] + width * 2,
scan[subpos] + width * 3,
};
// NOTE: Upper means "higher in pixel order inside block", which implies
// lower addresses (note the difference: HIGH and LOW vs UPPER and LOWER),
// so upper 128b vector actually becomes the lower part of a 256-bit coeff
// vector and lower vector the higher part!
__m128d coeffs_d_upper = _mm_castsi128_pd(_mm_set1_epi8(0));
__m128d coeffs_d_lower = _mm_castsi128_pd(_mm_set1_epi8(0));
__m128i coeffs_upper;
__m128i coeffs_lower;
__m128i coeffs_rearr1_upper;
__m128i coeffs_rearr1_lower;
__m128i coeffs_rearr2_upper;
__m128i coeffs_rearr2_lower;
coeffs_d_upper = _mm_loadl_pd(coeffs_d_upper, (double *)(coeff + row_offsets[0]));
coeffs_d_upper = _mm_loadh_pd(coeffs_d_upper, (double *)(coeff + row_offsets[1]));
coeffs_d_lower = _mm_loadl_pd(coeffs_d_lower, (double *)(coeff + row_offsets[2]));
coeffs_d_lower = _mm_loadh_pd(coeffs_d_lower, (double *)(coeff + row_offsets[3]));
coeffs_upper = _mm_castpd_si128(coeffs_d_upper);
coeffs_lower = _mm_castpd_si128(coeffs_d_lower);
coeffs_lower = _mm_shuffle_epi8(coeffs_lower, low128_shuffle_masks[scan_mode]);
coeffs_rearr1_upper = _mm_blendv_epi8(coeffs_upper, coeffs_lower, blend_masks[scan_mode]);
coeffs_rearr1_lower = _mm_blendv_epi8(coeffs_lower, coeffs_upper, blend_masks[scan_mode]);
coeffs_rearr2_upper = _mm_shuffle_epi8(coeffs_rearr1_upper, invec_rearr_masks_upper[scan_mode]);
coeffs_rearr2_lower = _mm_shuffle_epi8(coeffs_rearr1_lower, invec_rearr_masks_lower[scan_mode]);
// Why, oh why, is there no _mm256_setr_m128i intrinsic in the header that
// would do the exact same operation in the exact same way? :(
return _mm256_insertf128_si256(_mm256_castsi128_si256(coeffs_rearr2_upper),
coeffs_rearr2_lower,
1);
}
// If ints is completely zero, returns 16 in *first and -1 in *last
static INLINE void get_first_last_nz_int16(__m256i ints, int32_t *first, int32_t *last)
{
// Note that nonzero_bytes will always have both bytes set for a set word
// even if said word only had one of its bytes set, because we're doing 16
// bit wide comparisons. No big deal, just shift results to the right by one
// bit to have the results represent indexes of first set words, not bytes.
// Another note, it has to use right shift instead of division to preserve
// behavior on an all-zero vector (-1 / 2 == 0, but -1 >> 1 == -1)
const __m256i zero = _mm256_setzero_si256();
__m256i zeros = _mm256_cmpeq_epi16(ints, zero);
uint32_t nonzero_bytes = ~((uint32_t)_mm256_movemask_epi8(zeros));
*first = ( (int32_t)_tzcnt_u32(nonzero_bytes)) >> 1;
*last = (31 - (int32_t)_lzcnt_u32(nonzero_bytes)) >> 1;
}
/**
* \brief Encode (X,Y) position of the last significant coefficient
*
* \param lastpos_x X component of last coefficient
* \param lastpos_y Y component of last coefficient
* \param width Block width
* \param height Block height
* \param type plane type / luminance or chrominance
* \param scan scan type (diag, hor, ver)
*
* This method encodes the X and Y component within a block of the last
* significant coefficient.
*/
static void encode_last_significant_xy(cabac_data_t * const cabac,
uint8_t lastpos_x, uint8_t lastpos_y,
uint8_t width, uint8_t height,
uint8_t type, uint8_t scan)
{
const int index = kvz_math_floor_log2(width) - 2;
uint8_t ctx_offset = type ? 0 : (index * 3 + (index + 1) / 4);
uint8_t shift = type ? index : (index + 3) / 4;
cabac_ctx_t *base_ctx_x = (type ? cabac->ctx.cu_ctx_last_x_chroma : cabac->ctx.cu_ctx_last_x_luma);
cabac_ctx_t *base_ctx_y = (type ? cabac->ctx.cu_ctx_last_y_chroma : cabac->ctx.cu_ctx_last_y_luma);
if (scan == SCAN_VER) {
SWAP(lastpos_x, lastpos_y, uint8_t);
}
const int group_idx_x = g_group_idx[lastpos_x];
const int group_idx_y = g_group_idx[lastpos_y];
// x prefix
for (int last_x = 0; last_x < group_idx_x; last_x++) {
cabac->cur_ctx = &base_ctx_x[ctx_offset + (last_x >> shift)];
CABAC_BIN(cabac, 1, "last_sig_coeff_x_prefix");
}
if (group_idx_x < g_group_idx[width - 1]) {
cabac->cur_ctx = &base_ctx_x[ctx_offset + (group_idx_x >> shift)];
CABAC_BIN(cabac, 0, "last_sig_coeff_x_prefix");
}
// y prefix
for (int last_y = 0; last_y < group_idx_y; last_y++) {
cabac->cur_ctx = &base_ctx_y[ctx_offset + (last_y >> shift)];
CABAC_BIN(cabac, 1, "last_sig_coeff_y_prefix");
}
if (group_idx_y < g_group_idx[height - 1]) {
cabac->cur_ctx = &base_ctx_y[ctx_offset + (group_idx_y >> shift)];
CABAC_BIN(cabac, 0, "last_sig_coeff_y_prefix");
}
// last_sig_coeff_x_suffix
if (group_idx_x > 3) {
const int suffix = lastpos_x - g_min_in_group[group_idx_x];
const int bits = (group_idx_x - 2) / 2;
CABAC_BINS_EP(cabac, suffix, bits, "last_sig_coeff_x_suffix");
}
// last_sig_coeff_y_suffix
if (group_idx_y > 3) {
const int suffix = lastpos_y - g_min_in_group[group_idx_y];
const int bits = (group_idx_y - 2) / 2;
CABAC_BINS_EP(cabac, suffix, bits, "last_sig_coeff_y_suffix");
}
}
void kvz_encode_coeff_nxn_avx2(encoder_state_t * const state,
cabac_data_t * const cabac,
const coeff_t *coeff,
uint8_t width,
uint8_t type,
int8_t scan_mode,
int8_t tr_skip)
{
const encoder_control_t * const encoder = state->encoder_control;
int c1 = 1;
uint8_t last_coeff_x = 0;
uint8_t last_coeff_y = 0;
int32_t i;
uint32_t sig_coeffgroup_flag[8 * 8] = { 0 };
int8_t be_valid = encoder->cfg.signhide_enable;
int32_t scan_pos_sig;
uint32_t go_rice_param = 0;
uint32_t ctx_sig;
// CONSTANTS
const uint32_t num_blk_side = width >> TR_MIN_LOG2_SIZE;
const uint32_t log2_block_size = kvz_g_convert_to_bit[width] + 2;
const uint32_t *scan =
kvz_g_sig_last_scan[scan_mode][log2_block_size - 1];
const uint32_t *scan_cg = g_sig_last_scan_cg[log2_block_size - 2][scan_mode];
const uint32_t num_blocks = num_blk_side * num_blk_side;
const __m256i zero = _mm256_set1_epi8(0);
// Init base contexts according to block type
cabac_ctx_t *base_coeff_group_ctx = &(cabac->ctx.cu_sig_coeff_group_model[type]);
cabac_ctx_t *baseCtx = (type == 0) ? &(cabac->ctx.cu_sig_model_luma[0]) :
&(cabac->ctx.cu_sig_model_chroma[0]);
// Scan all coeff groups to find out which of them have coeffs.
// Populate sig_coeffgroup_flag with that info.
// NOTE: Modified the functionality a bit, sig_coeffgroup_flag used to be
// 1 if true and 0 if false, now it's "undefined but nonzero" if true and
// 0 if false (not actually undefined, it's a bitmask representing the
// significant coefficients' position in the group which in itself could
// be useful information)
int32_t scan_cg_last = -1;
for (int32_t i = 0; i < num_blocks; i++) {
const uint32_t cg_id = scan_cg[i];
const uint32_t n_xbits = log2_block_size - 2; // How many lowest bits of scan_cg represent X coord
const uint32_t cg_x = cg_id & ((1 << n_xbits) - 1);
const uint32_t cg_y = cg_id >> n_xbits;
const uint32_t cg_pos = cg_y * width * 4 + cg_x * 4;
const uint32_t cg_pos_y = (cg_pos >> log2_block_size) >> TR_MIN_LOG2_SIZE;
const uint32_t cg_pos_x = (cg_pos & (width - 1)) >> TR_MIN_LOG2_SIZE;
const uint32_t addr = cg_pos_x + cg_pos_y * num_blk_side;
__m128d coeffs_d_upper;
__m128d coeffs_d_lower;
__m128i coeffs_upper;
__m128i coeffs_lower;
__m256i cur_coeffs;
coeffs_d_upper = _mm_loadl_pd(coeffs_d_upper, (double *)(coeff + cg_pos + 0 * width));
coeffs_d_upper = _mm_loadh_pd(coeffs_d_upper, (double *)(coeff + cg_pos + 1 * width));
coeffs_d_lower = _mm_loadl_pd(coeffs_d_lower, (double *)(coeff + cg_pos + 2 * width));
coeffs_d_lower = _mm_loadh_pd(coeffs_d_lower, (double *)(coeff + cg_pos + 3 * width));
coeffs_upper = _mm_castpd_si128(coeffs_d_upper);
coeffs_lower = _mm_castpd_si128(coeffs_d_lower);
cur_coeffs = _mm256_insertf128_si256(_mm256_castsi128_si256(coeffs_upper),
coeffs_lower,
1);
__m256i coeffs_zero = _mm256_cmpeq_epi16(cur_coeffs, zero);
uint32_t nz_coeffs_2b = ~((uint32_t)_mm256_movemask_epi8(coeffs_zero));
sig_coeffgroup_flag[addr] = nz_coeffs_2b;
if (nz_coeffs_2b)
scan_cg_last = i;
}
// Rest of the code assumes at least one non-zero coeff.
assert(scan_cg_last >= 0);
ALIGNED(64) int16_t coeff_reord[LCU_WIDTH * LCU_WIDTH];
for (int32_t i = scan_cg_last; i >= 0; i--) {
int32_t subpos = i * 16;
__m256i coeffs_r = scanord_read_vector(coeff, scan, scan_mode, subpos, width);
_mm256_store_si256((__m256i *)(coeff_reord + subpos), coeffs_r);
}
// Find the last coeff by going backwards in scan order.
uint32_t scan_pos_last;
uint32_t baseaddr = scan_cg_last * 16;
__m256i cur_coeffs = _mm256_loadu_si256((__m256i *)(coeff_reord + baseaddr));
__m256i cur_coeffs_zeros = _mm256_cmpeq_epi16(cur_coeffs, zero);
uint32_t nz_bytes = ~(_mm256_movemask_epi8(cur_coeffs_zeros));
scan_pos_last = baseaddr + ((31 - _lzcnt_u32(nz_bytes)) >> 1);
int pos_last = scan[scan_pos_last];
// transform skip flag
if(width == 4 && encoder->cfg.trskip_enable) {
cabac->cur_ctx = (type == 0) ? &(cabac->ctx.transform_skip_model_luma) : &(cabac->ctx.transform_skip_model_chroma);
CABAC_BIN(cabac, tr_skip, "transform_skip_flag");
}
last_coeff_x = pos_last & (width - 1);
last_coeff_y = (uint8_t)(pos_last >> log2_block_size);
// Code last_coeff_x and last_coeff_y
encode_last_significant_xy(cabac,
last_coeff_x,
last_coeff_y,
width,
width,
type,
scan_mode);
scan_pos_sig = scan_pos_last;
int32_t abs_coeff[16];
abs_coeff[0] = abs(coeff[pos_last]);
uint32_t coeff_signs = (coeff[pos_last] < 0);
int32_t num_non_zero = 1;
int32_t last_nz_pos_in_cg = scan_pos_sig;
int32_t first_nz_pos_in_cg = scan_pos_sig;
scan_pos_sig--;
// significant_coeff_flag
for (i = scan_cg_last; i >= 0; i--) {
int32_t sub_pos = i << 4; // LOG2_SCAN_SET_SIZE;
int32_t cg_blk_pos = scan_cg[i];
int32_t cg_pos_y = cg_blk_pos / num_blk_side;
int32_t cg_pos_x = cg_blk_pos - (cg_pos_y * num_blk_side);
go_rice_param = 0;
if (i == scan_cg_last || i == 0) {
sig_coeffgroup_flag[cg_blk_pos] = 1;
} else {
uint32_t sig_coeff_group = (sig_coeffgroup_flag[cg_blk_pos] != 0);
uint32_t ctx_sig = kvz_context_get_sig_coeff_group(sig_coeffgroup_flag, cg_pos_x,
cg_pos_y, width);
cabac->cur_ctx = &base_coeff_group_ctx[ctx_sig];
CABAC_BIN(cabac, sig_coeff_group, "coded_sub_block_flag");
}
if (sig_coeffgroup_flag[cg_blk_pos]) {
int32_t pattern_sig_ctx = kvz_context_calc_pattern_sig_ctx(sig_coeffgroup_flag,
cg_pos_x, cg_pos_y, width);
ALIGNED(64) int16_t abs_coeff_buf[16];
ALIGNED(32) int16_t pos_ys_buf[16];
ALIGNED(32) int16_t pos_xs_buf[16];
const __m256i coeff_pos_zero = _mm256_castsi128_si256(_mm_cvtsi32_si128(0xffff));
const __m128i log2_block_size_128 = _mm_cvtsi32_si128(log2_block_size);
__m256i coeffs = _mm256_load_si256((__m256i *)(coeff_reord + sub_pos));
__m256i sigs_inv = _mm256_cmpeq_epi16(coeffs, zero);
__m256i is = _mm256_set1_epi16(i);
__m256i is_zero = _mm256_cmpeq_epi16(is, zero);
__m256i coeffs_subzero = _mm256_cmpgt_epi16(zero, coeffs);
__m256i masked_coeffs = _mm256_andnot_si256(sigs_inv, coeffs);
__m256i abs_coeffs = _mm256_abs_epi16(masked_coeffs);
// TODO: obtain 16-bit block positions, maybe? :P
__m256i blk_poses_hi = _mm256_loadu_si256((__m256i *)(scan + sub_pos + 8));
__m256i blk_poses_lo = _mm256_loadu_si256((__m256i *)(scan + sub_pos + 0));
__m256i blk_poses_tmp = _mm256_packs_epi32(blk_poses_lo, blk_poses_hi);
__m256i blk_poses = _mm256_permute4x64_epi64(blk_poses_tmp, _MM_SHUFFLE(3, 1, 2, 0));
__m256i pos_ys = _mm256_srl_epi16(blk_poses, log2_block_size_128);
__m256i pos_xs = _mm256_sub_epi16(blk_poses, _mm256_sll_epi16(pos_ys, log2_block_size_128));
_mm256_store_si256((__m256i *)pos_ys_buf, pos_ys);
_mm256_store_si256((__m256i *)pos_xs_buf, pos_xs);
__m256i encode_sig_coeff_flags_inv = _mm256_andnot_si256(is_zero, coeff_pos_zero);
get_first_last_nz_int16(masked_coeffs, &first_nz_pos_in_cg, &last_nz_pos_in_cg);
_mm256_store_si256((__m256i *)abs_coeff_buf, abs_coeffs);
uint32_t esc_flags = ~(_mm256_movemask_epi8(encode_sig_coeff_flags_inv));
uint32_t sigs = ~(_mm256_movemask_epi8(sigs_inv));
uint32_t coeff_sign_buf = _mm256_movemask_epi8(coeffs_subzero);
for (; scan_pos_sig >= sub_pos; scan_pos_sig--) {
uint32_t id = scan_pos_sig - sub_pos;
uint32_t shamt = (id << 1) + 1;
uint32_t curr_sig = (sigs >> shamt) & 1;
uint32_t curr_esc_flag = (esc_flags >> shamt) & 1;
uint32_t curr_coeff_sign = (coeff_sign_buf >> shamt) & 1;
uint32_t curr_pos_x = pos_xs_buf[id];
uint32_t curr_pos_y = pos_ys_buf[id];
if (curr_esc_flag | num_non_zero) {
ctx_sig = kvz_context_get_sig_ctx_inc(pattern_sig_ctx, scan_mode, curr_pos_x, curr_pos_y,
log2_block_size, type);
cabac->cur_ctx = &baseCtx[ctx_sig];
CABAC_BIN(cabac, curr_sig, "sig_coeff_flag");
}
if (curr_sig) {
abs_coeff[num_non_zero] = abs_coeff_buf[id];
coeff_signs = 2 * coeff_signs + curr_coeff_sign;
num_non_zero++;
}
}
} else {
scan_pos_sig = sub_pos - 1;
}
if (num_non_zero > 0) {
bool sign_hidden = last_nz_pos_in_cg - first_nz_pos_in_cg >= 4 /* SBH_THRESHOLD */
&& !encoder->cfg.lossless;
uint32_t ctx_set = (i > 0 && type == 0) ? 2 : 0;
cabac_ctx_t *base_ctx_mod;
int32_t num_c1_flag, first_c2_flag_idx, idx, first_coeff2;
if (c1 == 0) {
ctx_set++;
}
c1 = 1;
base_ctx_mod = (type == 0) ? &(cabac->ctx.cu_one_model_luma[4 * ctx_set]) :
&(cabac->ctx.cu_one_model_chroma[4 * ctx_set]);
num_c1_flag = MIN(num_non_zero, C1FLAG_NUMBER);
first_c2_flag_idx = -1;
for (idx = 0; idx < num_c1_flag; idx++) {
uint32_t symbol = (abs_coeff[idx] > 1) ? 1 : 0;
cabac->cur_ctx = &base_ctx_mod[c1];
CABAC_BIN(cabac, symbol, "coeff_abs_level_greater1_flag");
if (symbol) {
c1 = 0;
if (first_c2_flag_idx == -1) {
first_c2_flag_idx = idx;
}
} else if ((c1 < 3) && (c1 > 0)) {
c1++;
}
}
if (c1 == 0) {
base_ctx_mod = (type == 0) ? &(cabac->ctx.cu_abs_model_luma[ctx_set]) :
&(cabac->ctx.cu_abs_model_chroma[ctx_set]);
if (first_c2_flag_idx != -1) {
uint8_t symbol = (abs_coeff[first_c2_flag_idx] > 2) ? 1 : 0;
cabac->cur_ctx = &base_ctx_mod[0];
CABAC_BIN(cabac, symbol, "coeff_abs_level_greater2_flag");
}
}
int32_t shiftamt = (be_valid && sign_hidden) ? 1 : 0;
int32_t nnz = num_non_zero - shiftamt;
coeff_signs >>= shiftamt;
if (!cabac->only_count) {
if (encoder->cfg.crypto_features & KVZ_CRYPTO_TRANSF_COEFF_SIGNS) {
coeff_signs ^= kvz_crypto_get_key(state->crypto_hdl, nnz);
}
}
CABAC_BINS_EP(cabac, coeff_signs, nnz, "coeff_sign_flag");
if (c1 == 0 || num_non_zero > C1FLAG_NUMBER) {
first_coeff2 = 1;
for (idx = 0; idx < num_non_zero; idx++) {
int32_t base_level = (idx < C1FLAG_NUMBER) ? (2 + first_coeff2) : 1;
if (abs_coeff[idx] >= base_level) {
if (!cabac->only_count && (encoder->cfg.crypto_features & KVZ_CRYPTO_TRANSF_COEFFS)) {
kvz_cabac_write_coeff_remain_encry(state, cabac, abs_coeff[idx] - base_level, go_rice_param, base_level);
} else {
kvz_cabac_write_coeff_remain(cabac, abs_coeff[idx] - base_level, go_rice_param);
}
if (abs_coeff[idx] > 3 * (1 << go_rice_param)) {
go_rice_param = MIN(go_rice_param + 1, 4);
}
}
if (abs_coeff[idx] >= 2) {
first_coeff2 = 0;
}
}
}
}
last_nz_pos_in_cg = -1;
first_nz_pos_in_cg = 16;
num_non_zero = 0;
coeff_signs = 0;
}
}
int kvz_strategy_register_encode_avx2(void* opaque, uint8_t bitdepth)
{
bool success = true;
success &= kvz_strategyselector_register(opaque, "encode_coeff_nxn", "avx2", 40, &kvz_encode_coeff_nxn_avx2);
return success;
}