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/*
* 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 <assert.h>
#include <limits.h>
#include "config/aom_scale_rtcd.h"
#include "aom_dsp/aom_dsp_common.h"
#include "aom_dsp/psnr.h"
#include "aom_mem/aom_mem.h"
#include "aom_ports/mem.h"
#include "av1/common/av1_common_int.h"
#include "av1/common/av1_loopfilter.h"
#include "av1/common/quant_common.h"
#include "av1/encoder/av1_quantize.h"
#include "av1/encoder/encoder.h"
#include "av1/encoder/picklpf.h"
// AV1 loop filter applies to the whole frame according to mi_rows and mi_cols,
// which are calculated based on aligned width and aligned height,
// In addition, if super res is enabled, it copies the whole frame
// according to the aligned width and height (av1_superres_upscale()).
// So we need to copy the whole filtered region, instead of the cropped region.
// For example, input image size is: 160x90.
// Then src->y_crop_width = 160, src->y_crop_height = 90.
// The aligned frame size is: src->y_width = 160, src->y_height = 96.
// AV1 aligns frame size to a multiple of 8, if there is
// chroma subsampling, it is able to ensure the chroma is also
// an integer number of mi units. mi unit is 4x4, 8 = 4 * 2, and 2 luma mi
// units correspond to 1 chroma mi unit if there is subsampling.
// See: aom_realloc_frame_buffer() in yv12config.c.
static void yv12_copy_plane(const YV12_BUFFER_CONFIG *src_bc,
YV12_BUFFER_CONFIG *dst_bc, int plane) {
switch (plane) {
case 0: aom_yv12_copy_y(src_bc, dst_bc, 0); break;
case 1: aom_yv12_copy_u(src_bc, dst_bc, 0); break;
case 2: aom_yv12_copy_v(src_bc, dst_bc, 0); break;
default: assert(plane >= 0 && plane <= 2); break;
}
}
static int get_max_filter_level(const AV1_COMP *cpi) {
if (is_stat_consumption_stage_twopass(cpi)) {
return cpi->ppi->twopass.section_intra_rating > 8 ? MAX_LOOP_FILTER * 3 / 4
: MAX_LOOP_FILTER;
} else {
return MAX_LOOP_FILTER;
}
}
static int64_t try_filter_frame(const YV12_BUFFER_CONFIG *sd,
AV1_COMP *const cpi, int filt_level,
int partial_frame, int plane, int dir) {
MultiThreadInfo *const mt_info = &cpi->mt_info;
int num_workers = mt_info->num_mod_workers[MOD_LPF];
AV1_COMMON *const cm = &cpi->common;
int64_t filt_err;
assert(plane >= 0 && plane <= 2);
int filter_level[2] = { filt_level, filt_level };
if (plane == 0 && dir == 0) filter_level[1] = cm->lf.filter_level[1];
if (plane == 0 && dir == 1) filter_level[0] = cm->lf.filter_level[0];
// set base filters for use of get_filter_level (av1_loopfilter.c) when in
// DELTA_LF mode
switch (plane) {
case 0:
cm->lf.filter_level[0] = filter_level[0];
cm->lf.filter_level[1] = filter_level[1];
break;
case 1: cm->lf.filter_level_u = filter_level[0]; break;
case 2: cm->lf.filter_level_v = filter_level[0]; break;
}
// lpf_opt_level = 1 : Enables dual/quad loop-filtering.
int lpf_opt_level = is_inter_tx_size_search_level_one(&cpi->sf.tx_sf);
av1_loop_filter_frame_mt(&cm->cur_frame->buf, cm, &cpi->td.mb.e_mbd, plane,
plane + 1, partial_frame, mt_info->workers,
num_workers, &mt_info->lf_row_sync, lpf_opt_level);
filt_err = aom_get_sse_plane(sd, &cm->cur_frame->buf, plane,
cm->seq_params->use_highbitdepth);
// Re-instate the unfiltered frame
yv12_copy_plane(&cpi->last_frame_uf, &cm->cur_frame->buf, plane);
return filt_err;
}
static int search_filter_level(const YV12_BUFFER_CONFIG *sd, AV1_COMP *cpi,
int partial_frame,
const int *last_frame_filter_level, int plane,
int dir) {
const AV1_COMMON *const cm = &cpi->common;
const int min_filter_level = 0;
const int max_filter_level = get_max_filter_level(cpi);
int filt_direction = 0;
int64_t best_err;
int filt_best;
// Start the search at the previous frame filter level unless it is now out of
// range.
int lvl;
switch (plane) {
case 0:
switch (dir) {
case 2:
lvl = (last_frame_filter_level[0] + last_frame_filter_level[1] + 1) >>
1;
break;
case 0:
case 1: lvl = last_frame_filter_level[dir]; break;
default: assert(dir >= 0 && dir <= 2); return 0;
}
break;
case 1: lvl = last_frame_filter_level[2]; break;
case 2: lvl = last_frame_filter_level[3]; break;
default: assert(plane >= 0 && plane <= 2); return 0;
}
int filt_mid = clamp(lvl, min_filter_level, max_filter_level);
int filter_step = filt_mid < 16 ? 4 : filt_mid / 4;
// Sum squared error at each filter level
int64_t ss_err[MAX_LOOP_FILTER + 1];
const int use_coarse_search = cpi->sf.lpf_sf.use_coarse_filter_level_search;
assert(use_coarse_search <= 1);
static const int min_filter_step_lookup[2] = { 0, 2 };
// min_filter_step_thesh determines the stopping criteria for the search.
// The search is terminated when filter_step equals min_filter_step_thesh.
const int min_filter_step_thesh = min_filter_step_lookup[use_coarse_search];
// Set each entry to -1
memset(ss_err, 0xFF, sizeof(ss_err));
yv12_copy_plane(&cm->cur_frame->buf, &cpi->last_frame_uf, plane);
best_err = try_filter_frame(sd, cpi, filt_mid, partial_frame, plane, dir);
filt_best = filt_mid;
ss_err[filt_mid] = best_err;
while (filter_step > min_filter_step_thesh) {
const int filt_high = AOMMIN(filt_mid + filter_step, max_filter_level);
const int filt_low = AOMMAX(filt_mid - filter_step, min_filter_level);
// Bias against raising loop filter in favor of lowering it.
int64_t bias = (best_err >> (15 - (filt_mid / 8))) * filter_step;
if ((is_stat_consumption_stage_twopass(cpi)) &&
(cpi->ppi->twopass.section_intra_rating < 20))
bias = (bias * cpi->ppi->twopass.section_intra_rating) / 20;
// yx, bias less for large block size
if (cm->features.tx_mode != ONLY_4X4) bias >>= 1;
if (filt_direction <= 0 && filt_low != filt_mid) {
// Get Low filter error score
if (ss_err[filt_low] < 0) {
ss_err[filt_low] =
try_filter_frame(sd, cpi, filt_low, partial_frame, plane, dir);
}
// If value is close to the best so far then bias towards a lower loop
// filter value.
if (ss_err[filt_low] < (best_err + bias)) {
// Was it actually better than the previous best?
if (ss_err[filt_low] < best_err) {
best_err = ss_err[filt_low];
}
filt_best = filt_low;
}
}
// Now look at filt_high
if (filt_direction >= 0 && filt_high != filt_mid) {
if (ss_err[filt_high] < 0) {
ss_err[filt_high] =
try_filter_frame(sd, cpi, filt_high, partial_frame, plane, dir);
}
// If value is significantly better than previous best, bias added against
// raising filter value
if (ss_err[filt_high] < (best_err - bias)) {
best_err = ss_err[filt_high];
filt_best = filt_high;
}
}
// Half the step distance if the best filter value was the same as last time
if (filt_best == filt_mid) {
filter_step /= 2;
filt_direction = 0;
} else {
filt_direction = (filt_best < filt_mid) ? -1 : 1;
filt_mid = filt_best;
}
}
return filt_best;
}
void av1_pick_filter_level(const YV12_BUFFER_CONFIG *sd, AV1_COMP *cpi,
LPF_PICK_METHOD method) {
AV1_COMMON *const cm = &cpi->common;
const SequenceHeader *const seq_params = cm->seq_params;
const int num_planes = av1_num_planes(cm);
struct loopfilter *const lf = &cm->lf;
int disable_filter_rt_screen = 0;
(void)sd;
// Enable loop filter sharpness only for allintra encoding mode,
// as frames do not have to serve as references to others
lf->sharpness_level =
cpi->oxcf.mode == ALLINTRA ? cpi->oxcf.algo_cfg.sharpness : 0;
if (cpi->oxcf.tune_cfg.content == AOM_CONTENT_SCREEN &&
cpi->oxcf.q_cfg.aq_mode == CYCLIC_REFRESH_AQ &&
cpi->sf.rt_sf.skip_lf_screen)
disable_filter_rt_screen = av1_cyclic_refresh_disable_lf_cdef(cpi);
if (disable_filter_rt_screen ||
cpi->oxcf.algo_cfg.loopfilter_control == LOOPFILTER_NONE ||
(cpi->oxcf.algo_cfg.loopfilter_control == LOOPFILTER_REFERENCE &&
cpi->ppi->rtc_ref.non_reference_frame)) {
lf->filter_level[0] = 0;
lf->filter_level[1] = 0;
return;
}
if (method == LPF_PICK_MINIMAL_LPF) {
lf->filter_level[0] = 0;
lf->filter_level[1] = 0;
} else if (method >= LPF_PICK_FROM_Q) {
const int min_filter_level = 0;
const int max_filter_level = get_max_filter_level(cpi);
const int q = av1_ac_quant_QTX(cm->quant_params.base_qindex, 0,
seq_params->bit_depth);
// based on tests result for rtc test set
// 0.04590 boosted or 0.02295 non-booseted in 18-bit fixed point
const int strength_boost_q_treshold = 0;
int inter_frame_multiplier =
(q > strength_boost_q_treshold ||
(cpi->sf.rt_sf.use_nonrd_pick_mode &&
cpi->common.width * cpi->common.height > 352 * 288))
? 12034
: 6017;
// Increase strength on base TL0 for temporal layers, for low-resoln,
// based on frame source_sad.
if (cpi->svc.number_temporal_layers > 1 &&
cpi->svc.temporal_layer_id == 0 &&
cpi->common.width * cpi->common.height <= 352 * 288 &&
cpi->sf.rt_sf.use_nonrd_pick_mode) {
if (cpi->rc.frame_source_sad > 100000)
inter_frame_multiplier = inter_frame_multiplier << 1;
else if (cpi->rc.frame_source_sad > 50000)
inter_frame_multiplier = 3 * (inter_frame_multiplier >> 1);
} else if (cpi->sf.rt_sf.use_fast_fixed_part) {
inter_frame_multiplier = inter_frame_multiplier << 1;
}
// These values were determined by linear fitting the result of the
// searched level for 8 bit depth:
// Keyframes: filt_guess = q * 0.06699 - 1.60817
// Other frames: filt_guess = q * inter_frame_multiplier + 2.48225
//
// And high bit depth separately:
// filt_guess = q * 0.316206 + 3.87252
int filt_guess;
switch (seq_params->bit_depth) {
case AOM_BITS_8:
filt_guess =
(cm->current_frame.frame_type == KEY_FRAME)
? ROUND_POWER_OF_TWO(q * 17563 - 421574, 18)
: ROUND_POWER_OF_TWO(q * inter_frame_multiplier + 650707, 18);
break;
case AOM_BITS_10:
filt_guess = ROUND_POWER_OF_TWO(q * 20723 + 4060632, 20);
break;
case AOM_BITS_12:
filt_guess = ROUND_POWER_OF_TWO(q * 20723 + 16242526, 22);
break;
default:
assert(0 &&
"bit_depth should be AOM_BITS_8, AOM_BITS_10 "
"or AOM_BITS_12");
return;
}
if (seq_params->bit_depth != AOM_BITS_8 &&
cm->current_frame.frame_type == KEY_FRAME)
filt_guess -= 4;
// TODO(chengchen): retrain the model for Y, U, V filter levels
lf->filter_level[0] = clamp(filt_guess, min_filter_level, max_filter_level);
lf->filter_level[1] = clamp(filt_guess, min_filter_level, max_filter_level);
lf->filter_level_u = clamp(filt_guess, min_filter_level, max_filter_level);
lf->filter_level_v = clamp(filt_guess, min_filter_level, max_filter_level);
if (cpi->oxcf.algo_cfg.loopfilter_control == LOOPFILTER_SELECTIVELY &&
!frame_is_intra_only(cm) && !cpi->rc.high_source_sad) {
if (cpi->oxcf.tune_cfg.content == AOM_CONTENT_SCREEN) {
lf->filter_level[0] = 0;
lf->filter_level[1] = 0;
} else {
const int num4x4 = (cm->width >> 2) * (cm->height >> 2);
const int newmv_thresh = 7;
const int distance_since_key_thresh = 5;
if ((cpi->td.rd_counts.newmv_or_intra_blocks * 100 / num4x4) <
newmv_thresh &&
cpi->rc.frames_since_key > distance_since_key_thresh) {
lf->filter_level[0] = 0;
lf->filter_level[1] = 0;
}
}
}
} else {
int last_frame_filter_level[4] = { 0 };
if (!frame_is_intra_only(cm)) {
last_frame_filter_level[0] = cpi->ppi->filter_level[0];
last_frame_filter_level[1] = cpi->ppi->filter_level[1];
last_frame_filter_level[2] = cpi->ppi->filter_level_u;
last_frame_filter_level[3] = cpi->ppi->filter_level_v;
}
// The frame buffer last_frame_uf is used to store the non-loop filtered
// reconstructed frame in search_filter_level().
if (aom_realloc_frame_buffer(
&cpi->last_frame_uf, cm->width, cm->height,
seq_params->subsampling_x, seq_params->subsampling_y,
seq_params->use_highbitdepth, cpi->oxcf.border_in_pixels,
cm->features.byte_alignment, NULL, NULL, NULL, false, 0))
aom_internal_error(cm->error, AOM_CODEC_MEM_ERROR,
"Failed to allocate last frame buffer");
lf->filter_level[0] = lf->filter_level[1] =
search_filter_level(sd, cpi, method == LPF_PICK_FROM_SUBIMAGE,
last_frame_filter_level, 0, 2);
if (method != LPF_PICK_FROM_FULL_IMAGE_NON_DUAL) {
lf->filter_level[0] =
search_filter_level(sd, cpi, method == LPF_PICK_FROM_SUBIMAGE,
last_frame_filter_level, 0, 0);
lf->filter_level[1] =
search_filter_level(sd, cpi, method == LPF_PICK_FROM_SUBIMAGE,
last_frame_filter_level, 0, 1);
}
if (num_planes > 1) {
lf->filter_level_u =
search_filter_level(sd, cpi, method == LPF_PICK_FROM_SUBIMAGE,
last_frame_filter_level, 1, 0);
lf->filter_level_v =
search_filter_level(sd, cpi, method == LPF_PICK_FROM_SUBIMAGE,
last_frame_filter_level, 2, 0);
}
}
}