/*****************************************************************************
* This file is part of Kvazaar HEVC encoder.
*
* Copyright (C) 2013-2014 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 General Public License version 2 as published
* by the Free Software Foundation.
*
* 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with Kvazaar. If not, see .
****************************************************************************/
/*
* \file
*/
#include "sao.h"
#include
#include
#include "picture.h"
// Offsets of a and b in relation to c.
// dir_offset[dir][a or b]
// | | a | a | a |
// | a c b | c | c | c |
// | | b | b | b |
static const vector2d g_sao_edge_offsets[SAO_NUM_EO][2] = {
{ { -1, 0 }, { 1, 0 } },
{ { 0, -1 }, { 0, 1 } },
{ { -1, -1 }, { 1, 1 } },
{ { 1, -1 }, { -1, 1 } }
};
// Mapping of edge_idx values to eo-classes.
static const unsigned g_sao_eo_idx_to_eo_category[] = { 1, 2, 0, 3, 4 };
// Mapping relationships between a, b and c to eo_idx.
#define EO_IDX(a, b, c) (2 + SIGN3((c) - (a)) + SIGN3((c) - (b)))
int sao_band_ddistortion(const pixel *orig_data, const pixel *rec_data,
int block_width, int block_height,
int band_pos, int sao_bands[4])
{
int y, x;
int shift = g_bitdepth-5;
int sum = 0;
for (y = 0; y < block_height; ++y) {
for (x = 0; x < block_width; ++x) {
int band = (rec_data[y * block_width + x] >> shift) - band_pos;
int offset = 0;
if (band >= 0 && band < 4) {
offset = sao_bands[band];
}
if (offset != 0) {
int diff = orig_data[y * block_width + x] - rec_data[y * block_width + x];
// Offset is applied to reconstruction, so it is subtracted from diff.
sum += (diff - offset) * (diff - offset) - diff * diff;
}
}
}
return sum;
}
int sao_edge_ddistortion(const pixel *orig_data, const pixel *rec_data,
int block_width, int block_height,
int eo_class, int offsets[NUM_SAO_EDGE_CATEGORIES])
{
int y, x;
int sum = 0;
vector2d a_ofs = g_sao_edge_offsets[eo_class][0];
vector2d b_ofs = g_sao_edge_offsets[eo_class][1];
for (y = 1; y < block_height - 1; ++y) {
for (x = 1; x < block_width - 1; ++x) {
const pixel *c_data = &rec_data[y * block_width + x];
pixel a = c_data[a_ofs.y * block_width + a_ofs.x];
pixel c = c_data[0];
pixel b = c_data[b_ofs.y * block_width + b_ofs.x];
int eo_idx = EO_IDX(a, b, c);
int eo_cat = g_sao_eo_idx_to_eo_category[eo_idx];
int offset = offsets[eo_cat];
if (offset != 0) {
int diff = orig_data[y * block_width + x] - c;
// Offset is applied to reconstruction, so it is subtracted from diff.
sum += (diff - offset) * (diff - offset) - diff * diff;
}
}
}
return sum;
}
void init_sao_info(sao_info *sao) {
sao->type = SAO_TYPE_NONE;
sao->merge_left_flag = 0;
sao->merge_up_flag = 0;
}
/**
* \brief Check merge conditions
*/
static int sao_check_merge(const sao_info *sao_candidate, int type,
int offsets[NUM_SAO_EDGE_CATEGORIES],
int band_position, int eo_class)
{
if (sao_candidate && sao_candidate->type == type) {
if (offsets[1] == sao_candidate->offsets[1] &&
offsets[2] == sao_candidate->offsets[2] &&
offsets[3] == sao_candidate->offsets[3] &&
offsets[4] == sao_candidate->offsets[4]) {
// Type must be BAND or EDGE
if ((type == SAO_TYPE_BAND && band_position == sao_candidate->band_position) ||
(type == SAO_TYPE_EDGE && eo_class == sao_candidate->eo_class)) {
return 1;
}
}
}
return 0;
}
static int sao_mode_bits_edge(int edge_class, int offsets[NUM_SAO_EDGE_CATEGORIES],
sao_info *sao_top, sao_info *sao_left)
{
int mode_bits = 0;
if ((sao_top != NULL && sao_check_merge(sao_top, SAO_TYPE_EDGE, offsets, 0, edge_class)) ||
(sao_left != NULL && sao_check_merge(sao_left, SAO_TYPE_EDGE, offsets, 0, edge_class))) {
mode_bits += 1;
} else {
sao_eo_cat edge_cat;
for (edge_cat = SAO_EO_CAT1; edge_cat <= SAO_EO_CAT4; ++edge_cat) {
int abs_offset = abs(offsets[edge_cat]);
if (abs_offset == 0 || abs_offset == SAO_ABS_OFFSET_MAX) {
mode_bits += abs_offset + 1;
} else {
mode_bits += abs_offset + 2;
}
}
}
return mode_bits;
}
static int sao_mode_bits_band(int band_position, int offsets[NUM_SAO_EDGE_CATEGORIES],
sao_info *sao_top, sao_info *sao_left)
{
int mode_bits = 0;
if ((sao_top != NULL && sao_check_merge(sao_top, SAO_TYPE_BAND, offsets, band_position, 0)) ||
(sao_left != NULL && sao_check_merge(sao_left, SAO_TYPE_BAND, offsets, band_position, 0))) {
mode_bits += 1;
} else {
sao_eo_cat edge_cat;
for (edge_cat = SAO_EO_CAT1; edge_cat <= SAO_EO_CAT4; ++edge_cat) {
int abs_offset = abs(offsets[edge_cat]);
if (abs_offset == 0 || abs_offset == SAO_ABS_OFFSET_MAX) {
mode_bits += abs_offset + 1;
} else {
mode_bits += abs_offset + 2;
}
}
}
return mode_bits;
}
/**
* \brief calculate an array of intensity correlations for each intensity value
*/
static void calc_sao_offset_array(const sao_info *sao, int *offset)
{
int val;
int values = (1<>shift;
if(cur_band >= sao->band_position && cur_band < sao->band_position+4) {
offset[val] = CLIP(0, values-1,val+sao->offsets[cur_band-sao->band_position+1]);
} else {
offset[val] = val;
}
}
}
/**
* \param orig_data Original pixel data. 64x64 for luma, 32x32 for chroma.
* \param rec_data Reconstructed pixel data. 64x64 for luma, 32x32 for chroma.
* \param sao_bands an array of bands for original and reconstructed block
*/
static int calc_sao_band_offsets(int sao_bands[2][32], int offsets[4],
int *band_position, int *rate)
{
int band;
int offset;
int best_dist;
int temp_dist;
int dist[32];
int temp_offsets[32];
int temp_rate[32];
int best_dist_pos = 0;
memset(dist, 0, 32*sizeof(int));
memset(temp_rate, 0, 32*sizeof(int));
// Calculate distortion for each band using N*h^2 - 2*h*E
for (band = 0; band < 32; band++) {
best_dist = INT_MAX;
offset = 0;
if (sao_bands[1][band] != 0) {
offset = (sao_bands[0][band] + (sao_bands[1][band] >> 1)) / sao_bands[1][band];
offset = CLIP(-SAO_ABS_OFFSET_MAX, SAO_ABS_OFFSET_MAX, offset);
}
dist[band] = offset==0?0:INT_MAX;
temp_offsets[band] = 0;
while(offset != 0) {
temp_dist = sao_bands[1][band]*offset*offset - 2*offset*sao_bands[0][band];
// Calculate used rate to code this
temp_rate[band] = abs(offset+2);
// When max offset, no need to signal final bit
if (abs(offset)==SAO_ABS_OFFSET_MAX) {
temp_rate[band] --;
}
// Store best distortion and offset
if(temp_dist < best_dist) {
dist[band] = temp_dist;
temp_offsets[band] = offset;
}
offset += (offset > 0) ? -1:1;
}
}
best_dist = INT_MAX;
//Find starting pos for best 4 band distortions
for (band = 0; band < 28; band++) {
temp_dist = dist[band] + dist[band+1] + dist[band+2] + dist[band+3];
if(temp_dist < best_dist) {
best_dist = temp_dist;
best_dist_pos = band;
}
}
*rate = temp_rate[best_dist_pos]+temp_rate[best_dist_pos+1]+
temp_rate[best_dist_pos+2]+temp_rate[best_dist_pos+3];
// Copy best offsets to output
memcpy(offsets, &temp_offsets[best_dist_pos], 4*sizeof(int));
*band_position = best_dist_pos;
return best_dist;
}
/**
* \param orig_data Original pixel data. 64x64 for luma, 32x32 for chroma.
* \param rec_data Reconstructed pixel data. 64x64 for luma, 32x32 for chroma.
* \param sao_bands an array of bands for original and reconstructed block
*/
static void calc_sao_bands(const pixel *orig_data, const pixel *rec_data,
int block_width, int block_height,
int sao_bands[2][32])
{
int y, x;
int shift = g_bitdepth-5;
//Loop pixels and take top 5 bits to classify different bands
for (y = 0; y < block_height; ++y) {
for (x = 0; x < block_width; ++x) {
sao_bands[0][rec_data[y * block_width + x]>>shift] += orig_data[y * block_width + x] - rec_data[y * block_width + x];
sao_bands[1][rec_data[y * block_width + x]>>shift]++;
}
}
}
/**
* \param orig_data Original pixel data. 64x64 for luma, 32x32 for chroma.
* \param rec_data Reconstructed pixel data. 64x64 for luma, 32x32 for chroma.
* \param dir_offsets
* \param is_chroma 0 for luma, 1 for chroma. Indicates
*/
static void calc_sao_edge_dir(const pixel *orig_data, const pixel *rec_data,
int eo_class, int block_width, int block_height,
int cat_sum_cnt[2][NUM_SAO_EDGE_CATEGORIES])
{
int y, x;
vector2d a_ofs = g_sao_edge_offsets[eo_class][0];
vector2d b_ofs = g_sao_edge_offsets[eo_class][1];
// Arrays orig_data and rec_data are quarter size for chroma.
// Don't sample the edge pixels because this function doesn't have access to
// their neighbours.
for (y = 1; y < block_height - 1; ++y) {
for (x = 1; x < block_width - 1; ++x) {
const pixel *c_data = &rec_data[y * block_width + x];
pixel a = c_data[a_ofs.y * block_width + a_ofs.x];
pixel c = c_data[0];
pixel b = c_data[b_ofs.y * block_width + b_ofs.x];
int eo_idx = EO_IDX(a, b, c);
int eo_cat = g_sao_eo_idx_to_eo_category[eo_idx];
cat_sum_cnt[0][eo_cat] += orig_data[y * block_width + x] - c;
cat_sum_cnt[1][eo_cat] += 1;
}
}
}
static void sao_reconstruct_color(const pixel *rec_data, pixel *new_rec_data,
const sao_info *sao,
int stride, int new_stride,
int block_width, int block_height)
{
int y, x;
// Arrays orig_data and rec_data are quarter size for chroma.
if(sao->type == SAO_TYPE_BAND) {
int offsets[1<eo_class][0];
vector2d b_ofs = g_sao_edge_offsets[sao->eo_class][1];
const pixel *c_data = &rec_data[y * stride + x];
pixel *new_data = &new_rec_data[y * new_stride + x];
pixel a = c_data[a_ofs.y * stride + a_ofs.x];
pixel c = c_data[0];
pixel b = c_data[b_ofs.y * stride + b_ofs.x];
int eo_idx = EO_IDX(a, b, c);
int eo_cat = g_sao_eo_idx_to_eo_category[eo_idx];
new_data[0] = (pixel)CLIP(0, (1 << BIT_DEPTH) - 1, c_data[0] + sao->offsets[eo_cat]);
}
}
}
}
/**
* \brief Calculate dimensions of the buffer used by sao reconstruction.
* \param pic Picture.
* \param sao Sao parameters.
* \param rec Top-left corner of the LCU
*/
static void sao_calc_band_block_dims(const picture *pic, color_index color_i,
vector2d *rec, vector2d *block)
{
const int is_chroma = (color_i != COLOR_Y ? 1 : 0);
int width = pic->width >> is_chroma;
int height = pic->height >> is_chroma;
int block_width = LCU_WIDTH >> is_chroma;
// Handle right and bottom, taking care of non-LCU sized CUs.
if (rec->y + block_width >= height) {
if (rec->y + block_width >= height) {
block->y = height - rec->y;
}
}
if (rec->x + block_width >= width) {
if (rec->x + block_width > width) {
block->x = width - rec->x;
}
}
rec->x = 0; rec->y = 0;
}
/**
* \brief Calculate dimensions of the buffer used by sao reconstruction.
*
* This function calculates 4 vectors that can be used to make the temporary
* buffers required by sao_reconstruct_color.
*
* Vector block is the area affected by sao. Vectors tr and br are top-left
* margin and bottom-right margin, which contain pixels that are not modified
* by the reconstruction of this LCU but are needed by the reconstruction.
* Vector rec is the offset from the CU to the required pixel area.
*
* The margins are always either 0 or 1, depending on the direction of the
* edge offset class.
*
* This also takes into account borders of the picture and non-LCU sized
* CU's at the bottom and right of the picture.
*
* \ CU + rec
* +------+
* |\ tl |
* | +--+ |
* | |\ block
* | | \| |
* | +--+ |
* | \ br
* +------+
*
* \param pic Picture.
* \param sao Sao parameters.
* \param rec Top-left corner of the LCU, modified to be top-left corner of
*/
static void sao_calc_edge_block_dims(const picture *pic, color_index color_i,
const sao_info *sao, vector2d *rec,
vector2d *tl, vector2d *br,
vector2d *block)
{
vector2d a_ofs = g_sao_edge_offsets[sao->eo_class][0];
vector2d b_ofs = g_sao_edge_offsets[sao->eo_class][1];
const int is_chroma = (color_i != COLOR_Y ? 1 : 0);
int width = pic->width >> is_chroma;
int height = pic->height >> is_chroma;
int block_width = LCU_WIDTH >> is_chroma;
// Handle top and left.
if (rec->y == 0) {
tl->y = 0;
if (a_ofs.y == -1 || b_ofs.y == -1) {
block->y -= 1;
tl->y += 1;
}
}
if (rec->x == 0) {
tl->x = 0;
if (a_ofs.x == -1 || b_ofs.x == -1) {
block->x -= 1;
tl->x += 1;
}
}
// Handle right and bottom, taking care of non-LCU sized CUs.
if (rec->y + block_width >= height) {
br->y = 0;
if (rec->y + block_width >= height) {
block->y = height - rec->y;
}
if (a_ofs.y == 1 || b_ofs.y == 1) {
block->y -= 1;
br->y += 1;
}
}
if (rec->x + block_width >= width) {
br->x = 0;
if (rec->x + block_width > width) {
block->x = width - rec->x;
}
if (a_ofs.x == 1 || b_ofs.x == 1) {
block->x -= 1;
br->x += 1;
}
}
rec->y = (rec->y == 0 ? 0 : -1);
rec->x = (rec->x == 0 ? 0 : -1);
}
void sao_reconstruct(picture *pic, const pixel *old_rec,
unsigned x_ctb, unsigned y_ctb,
const sao_info *sao, color_index color_i)
{
const int is_chroma = (color_i != COLOR_Y ? 1 : 0);
const int pic_stride = pic->width >> is_chroma;
const int lcu_stride = LCU_WIDTH >> is_chroma;
const int buf_stride = lcu_stride + 2;
pixel *recdata = pic->recdata[color_i];
pixel buf_rec[(LCU_WIDTH + 2) * (LCU_WIDTH + 2)];
pixel new_rec[LCU_WIDTH * LCU_WIDTH];
// Calling CU_TO_PIXEL with depth 1 is the same as using block size of 32.
pixel *lcu_rec = &recdata[CU_TO_PIXEL(x_ctb, y_ctb, is_chroma, pic_stride)];
const pixel *old_lcu_rec = &old_rec[CU_TO_PIXEL(x_ctb, y_ctb, is_chroma, pic_stride)];
vector2d ofs;
vector2d tl = { 1, 1 };
vector2d br = { 1, 1 };
vector2d block = { LCU_WIDTH, LCU_WIDTH };
if (sao->type == SAO_TYPE_NONE) {
return;
}
ofs.x = x_ctb * lcu_stride;
ofs.y = y_ctb * lcu_stride;
block.x = lcu_stride;
block.y = lcu_stride;
if (sao->type == SAO_TYPE_BAND) {
tl.x = 0; tl.y = 0;
br.x = 0; br.y = 0;
sao_calc_band_block_dims(pic, color_i, &ofs, &block);
}
else {
sao_calc_edge_block_dims(pic, color_i, sao, &ofs, &tl, &br, &block);
}
// Data to tmp buffer.
picture_blit_pixels(&old_lcu_rec[ofs.y * pic_stride + ofs.x],
buf_rec,
tl.x + block.x + br.x,
tl.y + block.y + br.y,
pic_stride, buf_stride);
sao_reconstruct_color(&buf_rec[tl.y * buf_stride + tl.x],
&new_rec[(ofs.y + tl.y) * lcu_stride + ofs.x + tl.x],
sao,
buf_stride, lcu_stride,
block.x, block.y);
// Copy reconstructed block from tmp buffer to rec image.
picture_blit_pixels(&new_rec[(tl.y + ofs.y) * lcu_stride + (tl.x + ofs.x)],
&lcu_rec[(tl.y + ofs.y) * pic_stride + (tl.x + ofs.x)],
block.x, block.y, lcu_stride, pic_stride);
}
static void sao_search_edge_sao(const pixel * data[], const pixel * recdata[],
int block_width, int block_height,
unsigned buf_cnt,
sao_info *sao_out, sao_info *sao_top,
sao_info *sao_left)
{
sao_eo_class edge_class;
// This array is used to calculate the mean offset used to minimize distortion.
int cat_sum_cnt[2][NUM_SAO_EDGE_CATEGORIES];
unsigned i = 0;
int temp_rate = 0;
memset(cat_sum_cnt, 0, sizeof(int) * 2 * NUM_SAO_EDGE_CATEGORIES);
sao_out->type = SAO_TYPE_EDGE;
sao_out->ddistortion = INT_MAX;
for (edge_class = SAO_EO0; edge_class <= SAO_EO3; ++edge_class) {
int edge_offset[NUM_SAO_EDGE_CATEGORIES];
int sum_ddistortion = 0;
sao_eo_cat edge_cat;
// Call calc_sao_edge_dir once for luma and twice for chroma.
for (i = 0; i < buf_cnt; ++i) {
calc_sao_edge_dir(data[i], recdata[i], edge_class,
block_width, block_height, cat_sum_cnt);
}
for (edge_cat = SAO_EO_CAT1; edge_cat <= SAO_EO_CAT4; ++edge_cat) {
int cat_sum = cat_sum_cnt[0][edge_cat];
int cat_cnt = cat_sum_cnt[1][edge_cat];
// The optimum offset can be calculated by getting the minima of the
// fast ddistortion estimation formula. The minima is the mean error
// and we round that to the nearest integer.
int offset = 0;
if (cat_cnt != 0) {
offset = (cat_sum + (cat_cnt >> 1)) / cat_cnt;
offset = CLIP(-SAO_ABS_OFFSET_MAX, SAO_ABS_OFFSET_MAX, offset);
}
// Sharpening edge offsets can't be encoded, so set them to 0 here.
if (edge_cat >= SAO_EO_CAT1 && edge_cat <= SAO_EO_CAT2 && offset < 0) {
offset = 0;
}
if (edge_cat >= SAO_EO_CAT3 && edge_cat <= SAO_EO_CAT4 && offset > 0) {
offset = 0;
}
edge_offset[edge_cat] = offset;
// The ddistortion is amount by which the SSE of data changes. It should
// be negative for all categories, if offset was chosen correctly.
// ddistortion = N * h^2 - 2 * h * E, where N is the number of samples
// and E is the sum of errors.
// It basically says that all pixels that are not improved by offset
// increase increase SSE by h^2 and all pixels that are improved by
// offset decrease SSE by h*E.
sum_ddistortion += cat_cnt * offset * offset - 2 * offset * cat_sum;
// Calculate used rate to code this
temp_rate += abs(offset+2);
// When max offset, no need to signal final bit
if (abs(offset)==SAO_ABS_OFFSET_MAX) {
temp_rate --;
}
}
// If can merge, use lower cost
if((sao_top != NULL && sao_check_merge(sao_top, SAO_TYPE_EDGE, edge_offset,0, edge_class)) ||
(sao_left != NULL && sao_check_merge(sao_left, SAO_TYPE_EDGE, edge_offset,0, edge_class))) {
temp_rate = 1;
}
sum_ddistortion += (int)((double)temp_rate*(g_cur_lambda_cost+0.5));
// SAO is not applied for category 0.
edge_offset[SAO_EO_CAT0] = 0;
// Choose the offset class that offers the least error after offset.
if (sum_ddistortion < sao_out->ddistortion) {
sao_out->eo_class = edge_class;
sao_out->ddistortion = sum_ddistortion;
memcpy(sao_out->offsets, edge_offset, sizeof(int) * NUM_SAO_EDGE_CATEGORIES);
}
}
}
static void sao_search_band_sao(const pixel * data[], const pixel * recdata[],
int block_width, int block_height,
unsigned buf_cnt,
sao_info *sao_out, sao_info *sao_top,
sao_info *sao_left)
{
unsigned i;
sao_out->type = SAO_TYPE_BAND;
sao_out->ddistortion = MAX_INT;
// Band offset
{
int sao_bands[2][32];
int temp_offsets[4];
int ddistortion;
int temp_rate = 0;
memset(sao_bands, 0, 2 * 32 * sizeof(int));
for (i = 0; i < buf_cnt; ++i) {
calc_sao_bands(data[i], recdata[i],block_width,
block_height,sao_bands);
}
ddistortion = calc_sao_band_offsets(sao_bands, temp_offsets, &sao_out->band_position, &temp_rate);
if((sao_top != NULL && sao_check_merge(sao_top, SAO_TYPE_BAND, temp_offsets,sao_out->band_position, 0)) ||
(sao_left != NULL && sao_check_merge(sao_left, SAO_TYPE_BAND, temp_offsets,sao_out->band_position, 0))) {
temp_rate = 1;
}
ddistortion += (int)((double)temp_rate*(g_cur_lambda_cost+0.5));
// Select band sao over edge sao when distortion is lower
if (ddistortion < sao_out->ddistortion) {
sao_out->type = SAO_TYPE_BAND;
sao_out->ddistortion = ddistortion;
memcpy(&sao_out->offsets[1], temp_offsets, sizeof(int) * 4);
}
}
}
/**
* \param data Array of pointers to reference pixels.
* \param recdata Array of pointers to reconstructed pixels.
* \param block_width Width of the area to be examined.
* \param block_height Height of the area to be examined.
* \param buf_cnt Number of pointers data and recdata have.
* \param sao_out Output parameter for the best sao parameters.
*/
static void sao_search_best_mode(const pixel * data[], const pixel * recdata[],
int block_width, int block_height,
unsigned buf_cnt,
sao_info *sao_out, sao_info *sao_top,
sao_info *sao_left)
{
sao_info edge_sao;
sao_info band_sao;
sao_search_edge_sao(data, recdata, block_width, block_height, buf_cnt, &edge_sao, sao_top, sao_left);
sao_search_band_sao(data, recdata, block_width, block_height, buf_cnt, &band_sao, sao_top, sao_left);
{
int mode_bits = sao_mode_bits_edge(edge_sao.eo_class, edge_sao.offsets, sao_top, sao_left);
int ddistortion = mode_bits * (int)(g_cur_lambda_cost + 0.5);
unsigned buf_i;
for (buf_i = 0; buf_i < buf_cnt; ++buf_i) {
ddistortion += sao_edge_ddistortion(data[buf_i], recdata[buf_i],
block_width, block_height,
edge_sao.eo_class, edge_sao.offsets);
}
edge_sao.ddistortion = ddistortion;
}
{
int mode_bits = sao_mode_bits_band(band_sao.band_position, band_sao.offsets, sao_top, sao_left);
int ddistortion = mode_bits * (int)(g_cur_lambda_cost + 0.5);
unsigned buf_i;
for (buf_i = 0; buf_i < buf_cnt; ++buf_i) {
ddistortion += sao_band_ddistortion(data[buf_i], recdata[buf_i],
block_width, block_height,
band_sao.band_position, &band_sao.offsets[1]);
}
band_sao.ddistortion = ddistortion;
}
if (edge_sao.ddistortion <= band_sao.ddistortion) {
*sao_out = edge_sao;
} else {
*sao_out = band_sao;
}
// When BD-rate would increase because of SAO, disable it
if(sao_out->ddistortion >= 0) {
sao_out->type = SAO_TYPE_NONE;
}
sao_out->merge_up_flag = sao_check_merge(sao_top, sao_out->type, sao_out->offsets,
sao_out->band_position, sao_out->eo_class);
sao_out->merge_left_flag = sao_check_merge(sao_left, sao_out->type, sao_out->offsets,
sao_out->band_position, sao_out->eo_class);
return;
}
void sao_search_chroma(const picture *pic, unsigned x_ctb, unsigned y_ctb, sao_info *sao, sao_info *sao_top, sao_info *sao_left)
{
int block_width = (LCU_WIDTH / 2);
int block_height = (LCU_WIDTH / 2);
const pixel *orig_list[2];
const pixel *rec_list[2];
pixel orig[2][LCU_CHROMA_SIZE];
pixel rec[2][LCU_CHROMA_SIZE];
color_index color_i;
// Check for right and bottom boundaries.
if (x_ctb * (LCU_WIDTH / 2) + (LCU_WIDTH / 2) >= (unsigned)pic->width / 2) {
block_width = (pic->width - x_ctb * LCU_WIDTH) / 2;
}
if (y_ctb * (LCU_WIDTH / 2) + (LCU_WIDTH / 2) >= (unsigned)pic->height / 2) {
block_height = (pic->height - y_ctb * LCU_WIDTH) / 2;
}
sao->type = SAO_TYPE_EDGE;
// Copy data to temporary buffers and init orig and rec lists to point to those buffers.
for (color_i = COLOR_U; color_i <= COLOR_V; ++color_i) {
pixel *data = &pic->data[color_i][CU_TO_PIXEL(x_ctb, y_ctb, 1, pic->width / 2)];
pixel *recdata = &pic->recdata[color_i][CU_TO_PIXEL(x_ctb, y_ctb, 1, pic->width / 2)];
picture_blit_pixels(data, orig[color_i - 1], block_width, block_height,
pic->width / 2, block_width / 2);
picture_blit_pixels(recdata, rec[color_i - 1], block_width, block_height,
pic->width / 2, block_width / 2);
orig_list[color_i - 1] = &orig[color_i - 1][0];
rec_list[color_i - 1] = &rec[color_i - 1][0];
}
// Calculate
sao_search_best_mode(orig_list, rec_list, block_width / 2, block_height / 2, 2, sao, sao_top, sao_left);
}
void sao_search_luma(const picture *pic, unsigned x_ctb, unsigned y_ctb, sao_info *sao, sao_info *sao_top, sao_info *sao_left)
{
pixel orig[LCU_LUMA_SIZE];
pixel rec[LCU_LUMA_SIZE];
const pixel * orig_list[1] = { NULL };
const pixel * rec_list[1] = { NULL };
pixel *data = &pic->y_data[CU_TO_PIXEL(x_ctb, y_ctb, 0, pic->width)];
pixel *recdata = &pic->y_recdata[CU_TO_PIXEL(x_ctb, y_ctb, 0, pic->width)];
int block_width = LCU_WIDTH;
int block_height = LCU_WIDTH;
// Check for right and bottom boundaries.
if (x_ctb * LCU_WIDTH + LCU_WIDTH >= (unsigned)pic->width) {
block_width = pic->width - x_ctb * LCU_WIDTH;
}
if (y_ctb * LCU_WIDTH + LCU_WIDTH >= (unsigned)pic->height) {
block_height = pic->height - y_ctb * LCU_WIDTH;
}
sao->type = SAO_TYPE_EDGE;
// Fill temporary buffers with picture data.
picture_blit_pixels(data, orig, block_width, block_height, pic->width, block_width);
picture_blit_pixels(recdata, rec, block_width, block_height, pic->width, block_width);
orig_list[0] = orig;
rec_list[0] = rec;
sao_search_best_mode(orig_list, rec_list, block_width, block_height, 1, sao, sao_top, sao_left);
}
void sao_reconstruct_frame(const encoder_control * const encoder)
{
vector2d lcu;
picture *pic = encoder->in.cur_pic;
// These are needed because SAO needs the pre-SAO pixels form left and
// top LCUs. Single pixel wide buffers, like what search_lcu takes, would
// be enough though.
pixel *new_y_data = MALLOC(pixel, pic->width * pic->height);
pixel *new_u_data = MALLOC(pixel, (pic->width * pic->height) >> 2);
pixel *new_v_data = MALLOC(pixel, (pic->width * pic->height) >> 2);
memcpy(new_y_data, pic->y_recdata, sizeof(pixel) * pic->width * pic->height);
memcpy(new_u_data, pic->u_recdata, sizeof(pixel) * (pic->width * pic->height) >> 2);
memcpy(new_v_data, pic->v_recdata, sizeof(pixel) * (pic->width * pic->height) >> 2);
for (lcu.y = 0; lcu.y < encoder->in.height_in_lcu; lcu.y++) {
for (lcu.x = 0; lcu.x < encoder->in.width_in_lcu; lcu.x++) {
unsigned stride = encoder->in.width_in_lcu;
sao_info *sao_luma = &pic->sao_luma[lcu.y * stride + lcu.x];
sao_info *sao_chroma = &pic->sao_chroma[lcu.y * stride + lcu.x];
// sao_do_rdo(encoder, lcu.x, lcu.y, sao_luma, sao_chroma);
sao_reconstruct(pic, new_y_data, lcu.x, lcu.y, sao_luma, COLOR_Y);
sao_reconstruct(pic, new_u_data, lcu.x, lcu.y, sao_chroma, COLOR_U);
sao_reconstruct(pic, new_v_data, lcu.x, lcu.y, sao_chroma, COLOR_V);
}
}
free(new_y_data);
free(new_u_data);
free(new_v_data);
}