Files
vpx/av1/encoder/segmentation.c
Thomas Davies 80188d1546 Encode and decode multiple tile groups
This is a manual adaptation of the following commit from aom/master:
ce12003d60a1c8d6c65ed07ba165c34062fcbcbd

The original commit message:

A tile group is a set of tiles in scan order.

Each tile group has a version of uncompressed and compressed headers,
identical apart from tile group parameters.
Encoding probability updates takes account of the number of
headers to control overheads.

The decoder supports arbitrary numbers of tile groups with
arbitrary number of tiles. The number of tiles in a TG is
signalled in the uncompressed header for that TG.

The encoder currently only supports a fixed number
of TGs (3, when error resilient mode is on) of equal size
(except possibly for the last one).

The average BDR performnce with 3 tile groups versus
anchor with error resilient mode and up to 16 tiles is:

NR YCbCr:      3.02%      3.04%      3.05%
PSNRHVS:      3.09%
SSIM:      3.06%
MSSSIM:      3.05%
CIEDE2000:      3.04%

Change-Id: I9b97c5ed733103b9160a3a5d4370de5322c00c0b
2016-10-28 11:52:13 -07:00

391 lines
15 KiB
C

/*
* 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 <limits.h>
#include "aom_mem/aom_mem.h"
#include "av1/common/pred_common.h"
#include "av1/common/tile_common.h"
#include "av1/encoder/cost.h"
#include "av1/encoder/segmentation.h"
#include "av1/encoder/subexp.h"
void av1_enable_segmentation(struct segmentation *seg) {
seg->enabled = 1;
seg->update_map = 1;
seg->update_data = 1;
}
void av1_disable_segmentation(struct segmentation *seg) {
seg->enabled = 0;
seg->update_map = 0;
seg->update_data = 0;
}
void av1_set_segment_data(struct segmentation *seg, signed char *feature_data,
unsigned char abs_delta) {
seg->abs_delta = abs_delta;
memcpy(seg->feature_data, feature_data, sizeof(seg->feature_data));
}
void av1_disable_segfeature(struct segmentation *seg, int segment_id,
SEG_LVL_FEATURES feature_id) {
seg->feature_mask[segment_id] &= ~(1 << feature_id);
}
void av1_clear_segdata(struct segmentation *seg, int segment_id,
SEG_LVL_FEATURES feature_id) {
seg->feature_data[segment_id][feature_id] = 0;
}
// Based on set of segment counts calculate a probability tree
static void calc_segtree_probs(unsigned *segcounts,
aom_prob *segment_tree_probs,
const aom_prob *cur_tree_probs,
const int probwt) {
// Work out probabilities of each segment
const unsigned cc[4] = { segcounts[0] + segcounts[1],
segcounts[2] + segcounts[3],
segcounts[4] + segcounts[5],
segcounts[6] + segcounts[7] };
const unsigned ccc[2] = { cc[0] + cc[1], cc[2] + cc[3] };
int i;
segment_tree_probs[0] = get_binary_prob(ccc[0], ccc[1]);
segment_tree_probs[1] = get_binary_prob(cc[0], cc[1]);
segment_tree_probs[2] = get_binary_prob(cc[2], cc[3]);
segment_tree_probs[3] = get_binary_prob(segcounts[0], segcounts[1]);
segment_tree_probs[4] = get_binary_prob(segcounts[2], segcounts[3]);
segment_tree_probs[5] = get_binary_prob(segcounts[4], segcounts[5]);
segment_tree_probs[6] = get_binary_prob(segcounts[6], segcounts[7]);
for (i = 0; i < 7; i++) {
const unsigned *ct =
i == 0 ? ccc : i < 3 ? cc + (i & 2) : segcounts + (i - 3) * 2;
av1_prob_diff_update_savings_search(ct, cur_tree_probs[i],
&segment_tree_probs[i],
DIFF_UPDATE_PROB, probwt);
}
}
// Based on set of segment counts and probabilities calculate a cost estimate
static int cost_segmap(unsigned *segcounts, aom_prob *probs) {
const int c01 = segcounts[0] + segcounts[1];
const int c23 = segcounts[2] + segcounts[3];
const int c45 = segcounts[4] + segcounts[5];
const int c67 = segcounts[6] + segcounts[7];
const int c0123 = c01 + c23;
const int c4567 = c45 + c67;
// Cost the top node of the tree
int cost = c0123 * av1_cost_zero(probs[0]) + c4567 * av1_cost_one(probs[0]);
// Cost subsequent levels
if (c0123 > 0) {
cost += c01 * av1_cost_zero(probs[1]) + c23 * av1_cost_one(probs[1]);
if (c01 > 0)
cost += segcounts[0] * av1_cost_zero(probs[3]) +
segcounts[1] * av1_cost_one(probs[3]);
if (c23 > 0)
cost += segcounts[2] * av1_cost_zero(probs[4]) +
segcounts[3] * av1_cost_one(probs[4]);
}
if (c4567 > 0) {
cost += c45 * av1_cost_zero(probs[2]) + c67 * av1_cost_one(probs[2]);
if (c45 > 0)
cost += segcounts[4] * av1_cost_zero(probs[5]) +
segcounts[5] * av1_cost_one(probs[5]);
if (c67 > 0)
cost += segcounts[6] * av1_cost_zero(probs[6]) +
segcounts[7] * av1_cost_one(probs[6]);
}
return cost;
}
static void count_segs(const AV1_COMMON *cm, MACROBLOCKD *xd,
const TileInfo *tile, MODE_INFO **mi,
unsigned *no_pred_segcounts,
unsigned (*temporal_predictor_count)[2],
unsigned *t_unpred_seg_counts, int bw, int bh,
int mi_row, int mi_col) {
int segment_id;
if (mi_row >= cm->mi_rows || mi_col >= cm->mi_cols) return;
xd->mi = mi;
segment_id = xd->mi[0]->mbmi.segment_id;
set_mi_row_col(xd, tile, mi_row, bh, mi_col, bw, cm->mi_rows, cm->mi_cols);
// Count the number of hits on each segment with no prediction
no_pred_segcounts[segment_id]++;
// Temporal prediction not allowed on key frames
if (cm->frame_type != KEY_FRAME) {
const BLOCK_SIZE bsize = xd->mi[0]->mbmi.sb_type;
// Test to see if the segment id matches the predicted value.
const int pred_segment_id =
get_segment_id(cm, cm->last_frame_seg_map, bsize, mi_row, mi_col);
const int pred_flag = pred_segment_id == segment_id;
const int pred_context = av1_get_pred_context_seg_id(xd);
// Store the prediction status for this mb and update counts
// as appropriate
xd->mi[0]->mbmi.seg_id_predicted = pred_flag;
temporal_predictor_count[pred_context][pred_flag]++;
// Update the "unpredicted" segment count
if (!pred_flag) t_unpred_seg_counts[segment_id]++;
}
}
static void count_segs_sb(const AV1_COMMON *cm, MACROBLOCKD *xd,
const TileInfo *tile, MODE_INFO **mi,
unsigned *no_pred_segcounts,
unsigned (*temporal_predictor_count)[2],
unsigned *t_unpred_seg_counts, int mi_row, int mi_col,
BLOCK_SIZE bsize) {
const int mis = cm->mi_stride;
const int bs = num_8x8_blocks_wide_lookup[bsize], hbs = bs / 2;
#if CONFIG_EXT_PARTITION_TYPES
PARTITION_TYPE partition;
#else
int bw, bh;
#endif // CONFIG_EXT_PARTITION_TYPES
if (mi_row >= cm->mi_rows || mi_col >= cm->mi_cols) return;
#if CONFIG_EXT_PARTITION_TYPES
if (bsize == BLOCK_8X8)
partition = PARTITION_NONE;
else
partition = get_partition(cm, mi_row, mi_col, bsize);
switch (partition) {
case PARTITION_NONE:
count_segs(cm, xd, tile, mi, no_pred_segcounts, temporal_predictor_count,
t_unpred_seg_counts, bs, bs, mi_row, mi_col);
break;
case PARTITION_HORZ:
count_segs(cm, xd, tile, mi, no_pred_segcounts, temporal_predictor_count,
t_unpred_seg_counts, bs, hbs, mi_row, mi_col);
count_segs(cm, xd, tile, mi + hbs * mis, no_pred_segcounts,
temporal_predictor_count, t_unpred_seg_counts, bs, hbs,
mi_row + hbs, mi_col);
break;
case PARTITION_VERT:
count_segs(cm, xd, tile, mi, no_pred_segcounts, temporal_predictor_count,
t_unpred_seg_counts, hbs, bs, mi_row, mi_col);
count_segs(cm, xd, tile, mi + hbs, no_pred_segcounts,
temporal_predictor_count, t_unpred_seg_counts, hbs, bs, mi_row,
mi_col + hbs);
break;
case PARTITION_HORZ_A:
count_segs(cm, xd, tile, mi, no_pred_segcounts, temporal_predictor_count,
t_unpred_seg_counts, hbs, hbs, mi_row, mi_col);
count_segs(cm, xd, tile, mi + hbs, no_pred_segcounts,
temporal_predictor_count, t_unpred_seg_counts, hbs, hbs,
mi_row, mi_col + hbs);
count_segs(cm, xd, tile, mi + hbs * mis, no_pred_segcounts,
temporal_predictor_count, t_unpred_seg_counts, bs, hbs,
mi_row + hbs, mi_col);
break;
case PARTITION_HORZ_B:
count_segs(cm, xd, tile, mi, no_pred_segcounts, temporal_predictor_count,
t_unpred_seg_counts, bs, hbs, mi_row, mi_col);
count_segs(cm, xd, tile, mi + hbs * mis, no_pred_segcounts,
temporal_predictor_count, t_unpred_seg_counts, hbs, hbs,
mi_row + hbs, mi_col);
count_segs(cm, xd, tile, mi + hbs + hbs * mis, no_pred_segcounts,
temporal_predictor_count, t_unpred_seg_counts, hbs, hbs,
mi_row + hbs, mi_col + hbs);
break;
case PARTITION_VERT_A:
count_segs(cm, xd, tile, mi, no_pred_segcounts, temporal_predictor_count,
t_unpred_seg_counts, hbs, hbs, mi_row, mi_col);
count_segs(cm, xd, tile, mi + hbs * mis, no_pred_segcounts,
temporal_predictor_count, t_unpred_seg_counts, hbs, hbs,
mi_row + hbs, mi_col);
count_segs(cm, xd, tile, mi + hbs, no_pred_segcounts,
temporal_predictor_count, t_unpred_seg_counts, hbs, bs, mi_row,
mi_col + hbs);
break;
case PARTITION_VERT_B:
count_segs(cm, xd, tile, mi, no_pred_segcounts, temporal_predictor_count,
t_unpred_seg_counts, hbs, bs, mi_row, mi_col);
count_segs(cm, xd, tile, mi + hbs, no_pred_segcounts,
temporal_predictor_count, t_unpred_seg_counts, hbs, hbs,
mi_row, mi_col + hbs);
count_segs(cm, xd, tile, mi + hbs + hbs * mis, no_pred_segcounts,
temporal_predictor_count, t_unpred_seg_counts, hbs, hbs,
mi_row + hbs, mi_col + hbs);
break;
case PARTITION_SPLIT: {
const BLOCK_SIZE subsize = subsize_lookup[PARTITION_SPLIT][bsize];
int n;
assert(num_8x8_blocks_wide_lookup[mi[0]->mbmi.sb_type] < bs &&
num_8x8_blocks_high_lookup[mi[0]->mbmi.sb_type] < bs);
for (n = 0; n < 4; n++) {
const int mi_dc = hbs * (n & 1);
const int mi_dr = hbs * (n >> 1);
count_segs_sb(cm, xd, tile, &mi[mi_dr * mis + mi_dc], no_pred_segcounts,
temporal_predictor_count, t_unpred_seg_counts,
mi_row + mi_dr, mi_col + mi_dc, subsize);
}
} break;
default: assert(0);
}
#else
bw = num_8x8_blocks_wide_lookup[mi[0]->mbmi.sb_type];
bh = num_8x8_blocks_high_lookup[mi[0]->mbmi.sb_type];
if (bw == bs && bh == bs) {
count_segs(cm, xd, tile, mi, no_pred_segcounts, temporal_predictor_count,
t_unpred_seg_counts, bs, bs, mi_row, mi_col);
} else if (bw == bs && bh < bs) {
count_segs(cm, xd, tile, mi, no_pred_segcounts, temporal_predictor_count,
t_unpred_seg_counts, bs, hbs, mi_row, mi_col);
count_segs(cm, xd, tile, mi + hbs * mis, no_pred_segcounts,
temporal_predictor_count, t_unpred_seg_counts, bs, hbs,
mi_row + hbs, mi_col);
} else if (bw < bs && bh == bs) {
count_segs(cm, xd, tile, mi, no_pred_segcounts, temporal_predictor_count,
t_unpred_seg_counts, hbs, bs, mi_row, mi_col);
count_segs(cm, xd, tile, mi + hbs, no_pred_segcounts,
temporal_predictor_count, t_unpred_seg_counts, hbs, bs, mi_row,
mi_col + hbs);
} else {
const BLOCK_SIZE subsize = subsize_lookup[PARTITION_SPLIT][bsize];
int n;
assert(bw < bs && bh < bs);
for (n = 0; n < 4; n++) {
const int mi_dc = hbs * (n & 1);
const int mi_dr = hbs * (n >> 1);
count_segs_sb(cm, xd, tile, &mi[mi_dr * mis + mi_dc], no_pred_segcounts,
temporal_predictor_count, t_unpred_seg_counts,
mi_row + mi_dr, mi_col + mi_dc, subsize);
}
}
#endif // CONFIG_EXT_PARTITION_TYPES
}
void av1_choose_segmap_coding_method(AV1_COMMON *cm, MACROBLOCKD *xd) {
struct segmentation *seg = &cm->seg;
struct segmentation_probs *segp = &cm->fc->seg;
int no_pred_cost;
int t_pred_cost = INT_MAX;
int i, tile_col, tile_row, mi_row, mi_col;
#if CONFIG_TILE_GROUPS
const int probwt = cm->num_tg;
#else
const int probwt = 1;
#endif
unsigned(*temporal_predictor_count)[2] = cm->counts.seg.pred;
unsigned *no_pred_segcounts = cm->counts.seg.tree_total;
unsigned *t_unpred_seg_counts = cm->counts.seg.tree_mispred;
aom_prob no_pred_tree[SEG_TREE_PROBS];
aom_prob t_pred_tree[SEG_TREE_PROBS];
aom_prob t_nopred_prob[PREDICTION_PROBS];
(void)xd;
// We are about to recompute all the segment counts, so zero the accumulators.
av1_zero(cm->counts.seg);
// First of all generate stats regarding how well the last segment map
// predicts this one
for (tile_row = 0; tile_row < cm->tile_rows; tile_row++) {
TileInfo tile_info;
av1_tile_set_row(&tile_info, cm, tile_row);
for (tile_col = 0; tile_col < cm->tile_cols; tile_col++) {
MODE_INFO **mi_ptr;
av1_tile_set_col(&tile_info, cm, tile_col);
mi_ptr = cm->mi_grid_visible + tile_info.mi_row_start * cm->mi_stride +
tile_info.mi_col_start;
for (mi_row = tile_info.mi_row_start; mi_row < tile_info.mi_row_end;
mi_row += cm->mib_size, mi_ptr += cm->mib_size * cm->mi_stride) {
MODE_INFO **mi = mi_ptr;
for (mi_col = tile_info.mi_col_start; mi_col < tile_info.mi_col_end;
mi_col += cm->mib_size, mi += cm->mib_size) {
count_segs_sb(cm, xd, &tile_info, mi, no_pred_segcounts,
temporal_predictor_count, t_unpred_seg_counts, mi_row,
mi_col, cm->sb_size);
}
}
}
}
// Work out probability tree for coding segments without prediction
// and the cost.
calc_segtree_probs(no_pred_segcounts, no_pred_tree, segp->tree_probs, probwt);
no_pred_cost = cost_segmap(no_pred_segcounts, no_pred_tree);
// Key frames cannot use temporal prediction
if (!frame_is_intra_only(cm) && !cm->error_resilient_mode) {
// Work out probability tree for coding those segments not
// predicted using the temporal method and the cost.
calc_segtree_probs(t_unpred_seg_counts, t_pred_tree, segp->tree_probs,
probwt);
t_pred_cost = cost_segmap(t_unpred_seg_counts, t_pred_tree);
// Add in the cost of the signaling for each prediction context.
for (i = 0; i < PREDICTION_PROBS; i++) {
const int count0 = temporal_predictor_count[i][0];
const int count1 = temporal_predictor_count[i][1];
t_nopred_prob[i] = get_binary_prob(count0, count1);
av1_prob_diff_update_savings_search(
temporal_predictor_count[i], segp->pred_probs[i], &t_nopred_prob[i],
DIFF_UPDATE_PROB, probwt);
// Add in the predictor signaling cost
t_pred_cost += count0 * av1_cost_zero(t_nopred_prob[i]) +
count1 * av1_cost_one(t_nopred_prob[i]);
}
}
// Now choose which coding method to use.
if (t_pred_cost < no_pred_cost) {
assert(!cm->error_resilient_mode);
seg->temporal_update = 1;
} else {
seg->temporal_update = 0;
}
#if CONFIG_DAALA_EC
av1_tree_to_cdf(av1_segment_tree, segp->tree_probs, segp->tree_cdf);
#endif
}
void av1_reset_segment_features(AV1_COMMON *cm) {
struct segmentation *seg = &cm->seg;
// Set up default state for MB feature flags
seg->enabled = 0;
seg->update_map = 0;
seg->update_data = 0;
av1_clearall_segfeatures(seg);
}