Source code
Revision control
Copy as Markdown
Other Tools
/*
* Copyright (c) 2017, 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 "av1/decoder/decodetxb.h"
#include "aom_ports/mem.h"
#include "av1/common/idct.h"
#include "av1/common/scan.h"
#include "av1/common/txb_common.h"
#include "av1/decoder/decodemv.h"
#define ACCT_STR __func__
static int read_golomb(MACROBLOCKD *xd, aom_reader *r) {
int x = 1;
int length = 0;
int i = 0;
while (!i) {
i = aom_read_bit(r, ACCT_STR);
++length;
if (length > 20) {
aom_internal_error(xd->error_info, AOM_CODEC_CORRUPT_FRAME,
"Invalid length in read_golomb");
break;
}
}
for (i = 0; i < length - 1; ++i) {
x <<= 1;
x += aom_read_bit(r, ACCT_STR);
}
return x - 1;
}
static inline int rec_eob_pos(const int eob_token, const int extra) {
int eob = av1_eob_group_start[eob_token];
if (eob > 2) {
eob += extra;
}
return eob;
}
static inline int get_dqv(const int16_t *dequant, int coeff_idx,
const qm_val_t *iqmatrix) {
int dqv = dequant[!!coeff_idx];
if (iqmatrix != NULL)
dqv =
((iqmatrix[coeff_idx] * dqv) + (1 << (AOM_QM_BITS - 1))) >> AOM_QM_BITS;
return dqv;
}
static inline void read_coeffs_reverse_2d(aom_reader *r, TX_SIZE tx_size,
int start_si, int end_si,
const int16_t *scan, int bhl,
uint8_t *levels,
base_cdf_arr base_cdf,
br_cdf_arr br_cdf) {
for (int c = end_si; c >= start_si; --c) {
const int pos = scan[c];
const int coeff_ctx = get_lower_levels_ctx_2d(levels, pos, bhl, tx_size);
const int nsymbs = 4;
int level = aom_read_symbol(r, base_cdf[coeff_ctx], nsymbs, ACCT_STR);
if (level > NUM_BASE_LEVELS) {
const int br_ctx = get_br_ctx_2d(levels, pos, bhl);
aom_cdf_prob *cdf = br_cdf[br_ctx];
for (int idx = 0; idx < COEFF_BASE_RANGE; idx += BR_CDF_SIZE - 1) {
const int k = aom_read_symbol(r, cdf, BR_CDF_SIZE, ACCT_STR);
level += k;
if (k < BR_CDF_SIZE - 1) break;
}
}
levels[get_padded_idx(pos, bhl)] = level;
}
}
static inline void read_coeffs_reverse(aom_reader *r, TX_SIZE tx_size,
TX_CLASS tx_class, int start_si,
int end_si, const int16_t *scan, int bhl,
uint8_t *levels, base_cdf_arr base_cdf,
br_cdf_arr br_cdf) {
for (int c = end_si; c >= start_si; --c) {
const int pos = scan[c];
const int coeff_ctx =
get_lower_levels_ctx(levels, pos, bhl, tx_size, tx_class);
const int nsymbs = 4;
int level = aom_read_symbol(r, base_cdf[coeff_ctx], nsymbs, ACCT_STR);
if (level > NUM_BASE_LEVELS) {
const int br_ctx = get_br_ctx(levels, pos, bhl, tx_class);
aom_cdf_prob *cdf = br_cdf[br_ctx];
for (int idx = 0; idx < COEFF_BASE_RANGE; idx += BR_CDF_SIZE - 1) {
const int k = aom_read_symbol(r, cdf, BR_CDF_SIZE, ACCT_STR);
level += k;
if (k < BR_CDF_SIZE - 1) break;
}
}
levels[get_padded_idx(pos, bhl)] = level;
}
}
static uint8_t read_coeffs_txb(const AV1_COMMON *const cm,
DecoderCodingBlock *dcb, aom_reader *const r,
const int blk_row, const int blk_col,
const int plane, const TXB_CTX *const txb_ctx,
const TX_SIZE tx_size) {
MACROBLOCKD *const xd = &dcb->xd;
FRAME_CONTEXT *const ec_ctx = xd->tile_ctx;
const int32_t max_value = (1 << (7 + xd->bd)) - 1;
const int32_t min_value = -(1 << (7 + xd->bd));
const TX_SIZE txs_ctx = get_txsize_entropy_ctx(tx_size);
const PLANE_TYPE plane_type = get_plane_type(plane);
MB_MODE_INFO *const mbmi = xd->mi[0];
struct macroblockd_plane *const pd = &xd->plane[plane];
const int16_t *const dequant = pd->seg_dequant_QTX[mbmi->segment_id];
tran_low_t *const tcoeffs = dcb->dqcoeff_block[plane] + dcb->cb_offset[plane];
const int shift = av1_get_tx_scale(tx_size);
const int bhl = get_txb_bhl(tx_size);
const int width = get_txb_wide(tx_size);
const int height = get_txb_high(tx_size);
int cul_level = 0;
int dc_val = 0;
uint8_t levels_buf[TX_PAD_2D];
uint8_t *const levels = set_levels(levels_buf, height);
const int all_zero = aom_read_symbol(
r, ec_ctx->txb_skip_cdf[txs_ctx][txb_ctx->txb_skip_ctx], 2, ACCT_STR);
eob_info *eob_data = dcb->eob_data[plane] + dcb->txb_offset[plane];
uint16_t *const eob = &(eob_data->eob);
uint16_t *const max_scan_line = &(eob_data->max_scan_line);
*max_scan_line = 0;
*eob = 0;
#if CONFIG_INSPECTION
if (plane == 0) {
const int txk_type_idx =
av1_get_txk_type_index(mbmi->bsize, blk_row, blk_col);
mbmi->tx_skip[txk_type_idx] = all_zero;
}
#endif
if (all_zero) {
*max_scan_line = 0;
if (plane == 0) {
xd->tx_type_map[blk_row * xd->tx_type_map_stride + blk_col] = DCT_DCT;
}
return 0;
}
if (plane == AOM_PLANE_Y) {
// only y plane's tx_type is transmitted
av1_read_tx_type(cm, xd, blk_row, blk_col, tx_size, r);
}
const TX_TYPE tx_type =
av1_get_tx_type(xd, plane_type, blk_row, blk_col, tx_size,
cm->features.reduced_tx_set_used);
const TX_CLASS tx_class = tx_type_to_class[tx_type];
const qm_val_t *iqmatrix =
av1_get_iqmatrix(&cm->quant_params, xd, plane, tx_size, tx_type);
const SCAN_ORDER *const scan_order = get_scan(tx_size, tx_type);
const int16_t *const scan = scan_order->scan;
int eob_extra = 0;
int eob_pt = 1;
const int eob_multi_size = txsize_log2_minus4[tx_size];
const int eob_multi_ctx = (tx_class == TX_CLASS_2D) ? 0 : 1;
switch (eob_multi_size) {
case 0:
eob_pt =
aom_read_symbol(r, ec_ctx->eob_flag_cdf16[plane_type][eob_multi_ctx],
5, ACCT_STR) +
1;
break;
case 1:
eob_pt =
aom_read_symbol(r, ec_ctx->eob_flag_cdf32[plane_type][eob_multi_ctx],
6, ACCT_STR) +
1;
break;
case 2:
eob_pt =
aom_read_symbol(r, ec_ctx->eob_flag_cdf64[plane_type][eob_multi_ctx],
7, ACCT_STR) +
1;
break;
case 3:
eob_pt =
aom_read_symbol(r, ec_ctx->eob_flag_cdf128[plane_type][eob_multi_ctx],
8, ACCT_STR) +
1;
break;
case 4:
eob_pt =
aom_read_symbol(r, ec_ctx->eob_flag_cdf256[plane_type][eob_multi_ctx],
9, ACCT_STR) +
1;
break;
case 5:
eob_pt =
aom_read_symbol(r, ec_ctx->eob_flag_cdf512[plane_type][eob_multi_ctx],
10, ACCT_STR) +
1;
break;
case 6:
default:
eob_pt = aom_read_symbol(
r, ec_ctx->eob_flag_cdf1024[plane_type][eob_multi_ctx], 11,
ACCT_STR) +
1;
break;
}
const int eob_offset_bits = av1_eob_offset_bits[eob_pt];
if (eob_offset_bits > 0) {
const int eob_ctx = eob_pt - 3;
int bit = aom_read_symbol(
r, ec_ctx->eob_extra_cdf[txs_ctx][plane_type][eob_ctx], 2, ACCT_STR);
if (bit) {
eob_extra += (1 << (eob_offset_bits - 1));
}
for (int i = 1; i < eob_offset_bits; i++) {
bit = aom_read_bit(r, ACCT_STR);
if (bit) {
eob_extra += (1 << (eob_offset_bits - 1 - i));
}
}
}
*eob = rec_eob_pos(eob_pt, eob_extra);
if (*eob > 1) {
memset(levels_buf, 0,
sizeof(*levels_buf) *
((height + TX_PAD_HOR) * (width + TX_PAD_VER) + TX_PAD_END));
}
{
// Read the non-zero coefficient with scan index eob-1
// TODO(angiebird): Put this into a function
const int c = *eob - 1;
const int pos = scan[c];
const int coeff_ctx = get_lower_levels_ctx_eob(bhl, width, c);
const int nsymbs = 3;
aom_cdf_prob *cdf =
ec_ctx->coeff_base_eob_cdf[txs_ctx][plane_type][coeff_ctx];
int level = aom_read_symbol(r, cdf, nsymbs, ACCT_STR) + 1;
if (level > NUM_BASE_LEVELS) {
const int br_ctx = get_br_ctx_eob(pos, bhl, tx_class);
cdf = ec_ctx->coeff_br_cdf[AOMMIN(txs_ctx, TX_32X32)][plane_type][br_ctx];
for (int idx = 0; idx < COEFF_BASE_RANGE; idx += BR_CDF_SIZE - 1) {
const int k = aom_read_symbol(r, cdf, BR_CDF_SIZE, ACCT_STR);
level += k;
if (k < BR_CDF_SIZE - 1) break;
}
}
levels[get_padded_idx(pos, bhl)] = level;
}
if (*eob > 1) {
base_cdf_arr base_cdf = ec_ctx->coeff_base_cdf[txs_ctx][plane_type];
br_cdf_arr br_cdf =
ec_ctx->coeff_br_cdf[AOMMIN(txs_ctx, TX_32X32)][plane_type];
if (tx_class == TX_CLASS_2D) {
read_coeffs_reverse_2d(r, tx_size, 1, *eob - 1 - 1, scan, bhl, levels,
base_cdf, br_cdf);
read_coeffs_reverse(r, tx_size, tx_class, 0, 0, scan, bhl, levels,
base_cdf, br_cdf);
} else {
read_coeffs_reverse(r, tx_size, tx_class, 0, *eob - 1 - 1, scan, bhl,
levels, base_cdf, br_cdf);
}
}
for (int c = 0; c < *eob; ++c) {
const int pos = scan[c];
uint8_t sign;
tran_low_t level = levels[get_padded_idx(pos, bhl)];
if (level) {
*max_scan_line = AOMMAX(*max_scan_line, pos);
if (c == 0) {
const int dc_sign_ctx = txb_ctx->dc_sign_ctx;
sign = aom_read_symbol(r, ec_ctx->dc_sign_cdf[plane_type][dc_sign_ctx],
2, ACCT_STR);
} else {
sign = aom_read_bit(r, ACCT_STR);
}
if (level >= MAX_BASE_BR_RANGE) {
level += read_golomb(xd, r);
}
if (c == 0) dc_val = sign ? -level : level;
// Bitmasking to clamp level to valid range:
// The valid range for 8/10/12 bit vdieo is at most 14/16/18 bit
level &= 0xfffff;
cul_level += level;
tran_low_t dq_coeff;
// Bitmasking to clamp dq_coeff to valid range:
// The valid range for 8/10/12 bit video is at most 17/19/21 bit
dq_coeff =
(tran_low_t)((int64_t)level * get_dqv(dequant, scan[c], iqmatrix) &
0xffffff);
dq_coeff = dq_coeff >> shift;
if (sign) {
dq_coeff = -dq_coeff;
}
tcoeffs[pos] = clamp(dq_coeff, min_value, max_value);
}
}
cul_level = AOMMIN(COEFF_CONTEXT_MASK, cul_level);
// DC value
set_dc_sign(&cul_level, dc_val);
return cul_level;
}
void av1_read_coeffs_txb(const AV1_COMMON *const cm, DecoderCodingBlock *dcb,
aom_reader *const r, const int plane, const int row,
const int col, const TX_SIZE tx_size) {
#if TXCOEFF_TIMER
struct aom_usec_timer timer;
aom_usec_timer_start(&timer);
#endif
MACROBLOCKD *const xd = &dcb->xd;
MB_MODE_INFO *const mbmi = xd->mi[0];
struct macroblockd_plane *const pd = &xd->plane[plane];
const BLOCK_SIZE bsize = mbmi->bsize;
assert(bsize < BLOCK_SIZES_ALL);
const BLOCK_SIZE plane_bsize =
get_plane_block_size(bsize, pd->subsampling_x, pd->subsampling_y);
TXB_CTX txb_ctx;
get_txb_ctx(plane_bsize, tx_size, plane, pd->above_entropy_context + col,
pd->left_entropy_context + row, &txb_ctx);
const uint8_t cul_level =
read_coeffs_txb(cm, dcb, r, row, col, plane, &txb_ctx, tx_size);
av1_set_entropy_contexts(xd, pd, plane, plane_bsize, tx_size, cul_level, col,
row);
if (is_inter_block(mbmi)) {
const PLANE_TYPE plane_type = get_plane_type(plane);
// tx_type will be read out in av1_read_coeffs_txb_facade
const TX_TYPE tx_type = av1_get_tx_type(xd, plane_type, row, col, tx_size,
cm->features.reduced_tx_set_used);
if (plane == 0) {
const int txw = tx_size_wide_unit[tx_size];
const int txh = tx_size_high_unit[tx_size];
// The 16x16 unit is due to the constraint from tx_64x64 which sets the
// maximum tx size for chroma as 32x32. Coupled with 4x1 transform block
// size, the constraint takes effect in 32x16 / 16x32 size too. To solve
// the intricacy, cover all the 16x16 units inside a 64 level transform.
if (txw == tx_size_wide_unit[TX_64X64] ||
txh == tx_size_high_unit[TX_64X64]) {
const int tx_unit = tx_size_wide_unit[TX_16X16];
const int stride = xd->tx_type_map_stride;
for (int idy = 0; idy < txh; idy += tx_unit) {
for (int idx = 0; idx < txw; idx += tx_unit) {
xd->tx_type_map[(row + idy) * stride + col + idx] = tx_type;
}
}
}
}
}
#if TXCOEFF_TIMER
aom_usec_timer_mark(&timer);
const int64_t elapsed_time = aom_usec_timer_elapsed(&timer);
cm->txcoeff_timer += elapsed_time;
++cm->txb_count;
#endif
}