ref: b2597527a5364338f997c62e874083efcbef2f8a
dir: /vp9/decoder/vp9_detokenize.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 "vpx_mem/vpx_mem.h"
#include "vpx_ports/mem.h"
#include "vp9/common/vp9_blockd.h"
#include "vp9/common/vp9_common.h"
#include "vp9/common/vp9_entropy.h"
#if CONFIG_COEFFICIENT_RANGE_CHECKING
#include "vp9/common/vp9_idct.h"
#endif
#include "vp9/decoder/vp9_detokenize.h"
#define EOB_CONTEXT_NODE 0
#define ZERO_CONTEXT_NODE 1
#define ONE_CONTEXT_NODE 2
#define INCREMENT_COUNT(token) \
do { \
if (counts) \
++coef_counts[band][ctx][token]; \
} while (0)
static INLINE int read_coeff(const vpx_prob *probs, int n, vpx_reader *r) {
int i, val = 0;
for (i = 0; i < n; ++i)
val = (val << 1) | vpx_read(r, probs[i]);
return val;
}
static int decode_coefs(const MACROBLOCKD *xd,
PLANE_TYPE type,
tran_low_t *dqcoeff, TX_SIZE tx_size, const int16_t *dq,
int ctx, const int16_t *scan, const int16_t *nb,
vpx_reader *r) {
FRAME_COUNTS *counts = xd->counts;
const int max_eob = 16 << (tx_size << 1);
const FRAME_CONTEXT *const fc = xd->fc;
const int ref = is_inter_block(xd->mi[0]);
int band, c = 0;
const vpx_prob (*coef_probs)[COEFF_CONTEXTS][UNCONSTRAINED_NODES] =
fc->coef_probs[tx_size][type][ref];
const vpx_prob *prob;
unsigned int (*coef_counts)[COEFF_CONTEXTS][UNCONSTRAINED_NODES + 1];
unsigned int (*eob_branch_count)[COEFF_CONTEXTS];
uint8_t token_cache[32 * 32];
const uint8_t *band_translate = get_band_translate(tx_size);
const int dq_shift = (tx_size == TX_32X32);
int v, token;
int16_t dqv = dq[0];
const uint8_t *const cat6_prob =
#if CONFIG_VP9_HIGHBITDEPTH
(xd->bd == VPX_BITS_12) ? vp9_cat6_prob_high12 :
(xd->bd == VPX_BITS_10) ? vp9_cat6_prob_high12 + 2 :
#endif // CONFIG_VP9_HIGHBITDEPTH
vp9_cat6_prob;
const int cat6_bits =
#if CONFIG_VP9_HIGHBITDEPTH
(xd->bd == VPX_BITS_12) ? 18 :
(xd->bd == VPX_BITS_10) ? 16 :
#endif // CONFIG_VP9_HIGHBITDEPTH
14;
if (counts) {
coef_counts = counts->coef[tx_size][type][ref];
eob_branch_count = counts->eob_branch[tx_size][type][ref];
}
while (c < max_eob) {
int val = -1;
band = *band_translate++;
prob = coef_probs[band][ctx];
if (counts)
++eob_branch_count[band][ctx];
if (!vpx_read(r, prob[EOB_CONTEXT_NODE])) {
INCREMENT_COUNT(EOB_MODEL_TOKEN);
break;
}
while (!vpx_read(r, prob[ZERO_CONTEXT_NODE])) {
INCREMENT_COUNT(ZERO_TOKEN);
dqv = dq[1];
token_cache[scan[c]] = 0;
++c;
if (c >= max_eob)
return c; // zero tokens at the end (no eob token)
ctx = get_coef_context(nb, token_cache, c);
band = *band_translate++;
prob = coef_probs[band][ctx];
}
if (!vpx_read(r, prob[ONE_CONTEXT_NODE])) {
INCREMENT_COUNT(ONE_TOKEN);
token = ONE_TOKEN;
val = 1;
} else {
INCREMENT_COUNT(TWO_TOKEN);
token = vpx_read_tree(r, vp9_coef_con_tree,
vp9_pareto8_full[prob[PIVOT_NODE] - 1]);
switch (token) {
case TWO_TOKEN:
case THREE_TOKEN:
case FOUR_TOKEN:
val = token;
break;
case CATEGORY1_TOKEN:
val = CAT1_MIN_VAL + read_coeff(vp9_cat1_prob, 1, r);
break;
case CATEGORY2_TOKEN:
val = CAT2_MIN_VAL + read_coeff(vp9_cat2_prob, 2, r);
break;
case CATEGORY3_TOKEN:
val = CAT3_MIN_VAL + read_coeff(vp9_cat3_prob, 3, r);
break;
case CATEGORY4_TOKEN:
val = CAT4_MIN_VAL + read_coeff(vp9_cat4_prob, 4, r);
break;
case CATEGORY5_TOKEN:
val = CAT5_MIN_VAL + read_coeff(vp9_cat5_prob, 5, r);
break;
case CATEGORY6_TOKEN:
val = CAT6_MIN_VAL + read_coeff(cat6_prob, cat6_bits, r);
break;
}
}
v = (val * dqv) >> dq_shift;
#if CONFIG_COEFFICIENT_RANGE_CHECKING
#if CONFIG_VP9_HIGHBITDEPTH
dqcoeff[scan[c]] = highbd_check_range((vpx_read_bit(r) ? -v : v),
xd->bd);
#else
dqcoeff[scan[c]] = check_range(vpx_read_bit(r) ? -v : v);
#endif // CONFIG_VP9_HIGHBITDEPTH
#else
dqcoeff[scan[c]] = vpx_read_bit(r) ? -v : v;
#endif // CONFIG_COEFFICIENT_RANGE_CHECKING
token_cache[scan[c]] = vp9_pt_energy_class[token];
++c;
ctx = get_coef_context(nb, token_cache, c);
dqv = dq[1];
}
return c;
}
static void get_ctx_shift(MACROBLOCKD *xd, int *ctx_shift_a, int *ctx_shift_l,
int x, int y, unsigned int tx_size_in_blocks) {
if (xd->max_blocks_wide) {
if (tx_size_in_blocks + x > xd->max_blocks_wide)
*ctx_shift_a = (tx_size_in_blocks - (xd->max_blocks_wide - x)) * 8;
}
if (xd->max_blocks_high) {
if (tx_size_in_blocks + y > xd->max_blocks_high)
*ctx_shift_l = (tx_size_in_blocks - (xd->max_blocks_high - y)) * 8;
}
}
int vp9_decode_block_tokens(MACROBLOCKD *xd, int plane, const scan_order *sc,
int x, int y, TX_SIZE tx_size, vpx_reader *r,
int seg_id) {
struct macroblockd_plane *const pd = &xd->plane[plane];
const int16_t *const dequant = pd->seg_dequant[seg_id];
int eob;
ENTROPY_CONTEXT *a = pd->above_context + x;
ENTROPY_CONTEXT *l = pd->left_context + y;
int ctx;
int ctx_shift_a = 0;
int ctx_shift_l = 0;
switch (tx_size) {
case TX_4X4:
ctx = a[0] != 0;
ctx += l[0] != 0;
eob = decode_coefs(xd, get_plane_type(plane), pd->dqcoeff, tx_size,
dequant, ctx, sc->scan, sc->neighbors, r);
a[0] = l[0] = (eob > 0);
break;
case TX_8X8:
get_ctx_shift(xd, &ctx_shift_a, &ctx_shift_l, x, y, 1 << TX_8X8);
ctx = !!*(const uint16_t *)a;
ctx += !!*(const uint16_t *)l;
eob = decode_coefs(xd, get_plane_type(plane), pd->dqcoeff, tx_size,
dequant, ctx, sc->scan, sc->neighbors, r);
*(uint16_t *)a = ((eob > 0) * 0x0101) >> ctx_shift_a;
*(uint16_t *)l = ((eob > 0) * 0x0101) >> ctx_shift_l;
break;
case TX_16X16:
get_ctx_shift(xd, &ctx_shift_a, &ctx_shift_l, x, y, 1 << TX_16X16);
ctx = !!*(const uint32_t *)a;
ctx += !!*(const uint32_t *)l;
eob = decode_coefs(xd, get_plane_type(plane), pd->dqcoeff, tx_size,
dequant, ctx, sc->scan, sc->neighbors, r);
*(uint32_t *)a = ((eob > 0) * 0x01010101) >> ctx_shift_a;
*(uint32_t *)l = ((eob > 0) * 0x01010101) >> ctx_shift_l;
break;
case TX_32X32:
get_ctx_shift(xd, &ctx_shift_a, &ctx_shift_l, x, y, 1 << TX_32X32);
// NOTE: casting to uint64_t here is safe because the default memory
// alignment is at least 8 bytes and the TX_32X32 is aligned on 8 byte
// boundaries.
ctx = !!*(const uint64_t *)a;
ctx += !!*(const uint64_t *)l;
eob = decode_coefs(xd, get_plane_type(plane), pd->dqcoeff, tx_size,
dequant, ctx, sc->scan, sc->neighbors, r);
*(uint64_t *)a = ((eob > 0) * 0x0101010101010101ULL) >> ctx_shift_a;
*(uint64_t *)l = ((eob > 0) * 0x0101010101010101ULL) >> ctx_shift_l;
break;
default:
assert(0 && "Invalid transform size.");
eob = 0;
break;
}
return eob;
}