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vpx/vp9/common/vp9_reconinter.c

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/*
* 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 <assert.h>
#include "./vpx_scale_rtcd.h"
#include "./vpx_config.h"
#include "vpx/vpx_integer.h"
#include "vp9/common/vp9_blockd.h"
#include "vp9/common/vp9_filter.h"
#include "vp9/common/vp9_reconinter.h"
#include "vp9/common/vp9_reconintra.h"
static void build_mc_border(const uint8_t *src, int src_stride,
uint8_t *dst, int dst_stride,
int x, int y, int b_w, int b_h, int w, int h) {
// Get a pointer to the start of the real data for this row.
const uint8_t *ref_row = src - x - y * src_stride;
if (y >= h)
ref_row += (h - 1) * src_stride;
else if (y > 0)
ref_row += y * src_stride;
do {
int right = 0, copy;
int left = x < 0 ? -x : 0;
if (left > b_w)
left = b_w;
if (x + b_w > w)
right = x + b_w - w;
if (right > b_w)
right = b_w;
copy = b_w - left - right;
if (left)
memset(dst, ref_row[0], left);
if (copy)
memcpy(dst + left, ref_row + x + left, copy);
if (right)
memset(dst + left + copy, ref_row[w - 1], right);
dst += dst_stride;
++y;
if (y > 0 && y < h)
ref_row += src_stride;
} while (--b_h);
}
#if CONFIG_VP9_HIGHBITDEPTH
static void high_build_mc_border(const uint8_t *src8, int src_stride,
uint16_t *dst, int dst_stride,
int x, int y, int b_w, int b_h,
int w, int h) {
// Get a pointer to the start of the real data for this row.
const uint16_t *src = CONVERT_TO_SHORTPTR(src8);
const uint16_t *ref_row = src - x - y * src_stride;
if (y >= h)
ref_row += (h - 1) * src_stride;
else if (y > 0)
ref_row += y * src_stride;
do {
int right = 0, copy;
int left = x < 0 ? -x : 0;
if (left > b_w)
left = b_w;
if (x + b_w > w)
right = x + b_w - w;
if (right > b_w)
right = b_w;
copy = b_w - left - right;
if (left)
vpx_memset16(dst, ref_row[0], left);
if (copy)
memcpy(dst + left, ref_row + x + left, copy * sizeof(uint16_t));
if (right)
vpx_memset16(dst + left + copy, ref_row[w - 1], right);
dst += dst_stride;
++y;
if (y > 0 && y < h)
ref_row += src_stride;
} while (--b_h);
}
#endif // CONFIG_VP9_HIGHBITDEPTH
static void inter_predictor(const uint8_t *src, int src_stride,
uint8_t *dst, int dst_stride,
const int subpel_x,
const int subpel_y,
const struct scale_factors *sf,
int w, int h, int ref,
const InterpKernel *kernel,
int xs, int ys) {
sf->predict[subpel_x != 0][subpel_y != 0][ref](
src, src_stride, dst, dst_stride,
kernel[subpel_x], xs, kernel[subpel_y], ys, w, h);
}
void vp9_build_inter_predictor(const uint8_t *src, int src_stride,
uint8_t *dst, int dst_stride,
const MV *src_mv,
const struct scale_factors *sf,
int w, int h, int ref,
const InterpKernel *kernel,
enum mv_precision precision,
int x, int y) {
const int is_q4 = precision == MV_PRECISION_Q4;
const MV mv_q4 = { is_q4 ? src_mv->row : src_mv->row * 2,
is_q4 ? src_mv->col : src_mv->col * 2 };
MV32 mv = vp9_scale_mv(&mv_q4, x, y, sf);
const int subpel_x = mv.col & SUBPEL_MASK;
const int subpel_y = mv.row & SUBPEL_MASK;
src += (mv.row >> SUBPEL_BITS) * src_stride + (mv.col >> SUBPEL_BITS);
inter_predictor(src, src_stride, dst, dst_stride, subpel_x, subpel_y,
sf, w, h, ref, kernel, sf->x_step_q4, sf->y_step_q4);
}
#if CONFIG_VP9_HIGHBITDEPTH
static void high_inter_predictor(const uint8_t *src, int src_stride,
uint8_t *dst, int dst_stride,
const int subpel_x,
const int subpel_y,
const struct scale_factors *sf,
int w, int h, int ref,
const InterpKernel *kernel,
int xs, int ys, int bd) {
sf->high_predict[subpel_x != 0][subpel_y != 0][ref](
src, src_stride, dst, dst_stride,
kernel[subpel_x], xs, kernel[subpel_y], ys, w, h, bd);
}
void vp9_high_build_inter_predictor(const uint8_t *src, int src_stride,
uint8_t *dst, int dst_stride,
const MV *src_mv,
const struct scale_factors *sf,
int w, int h, int ref,
const InterpKernel *kernel,
enum mv_precision precision,
int x, int y, int bd) {
const int is_q4 = precision == MV_PRECISION_Q4;
const MV mv_q4 = { is_q4 ? src_mv->row : src_mv->row * 2,
is_q4 ? src_mv->col : src_mv->col * 2 };
MV32 mv = vp9_scale_mv(&mv_q4, x, y, sf);
const int subpel_x = mv.col & SUBPEL_MASK;
const int subpel_y = mv.row & SUBPEL_MASK;
src += (mv.row >> SUBPEL_BITS) * src_stride + (mv.col >> SUBPEL_BITS);
high_inter_predictor(src, src_stride, dst, dst_stride, subpel_x, subpel_y,
sf, w, h, ref, kernel, sf->x_step_q4, sf->y_step_q4, bd);
}
#endif // CONFIG_VP9_HIGHBITDEPTH
static INLINE int round_mv_comp_q4(int value) {
return (value < 0 ? value - 2 : value + 2) / 4;
}
static MV mi_mv_pred_q4(const MODE_INFO *mi, int idx) {
MV res = { round_mv_comp_q4(mi->bmi[0].as_mv[idx].as_mv.row +
mi->bmi[1].as_mv[idx].as_mv.row +
mi->bmi[2].as_mv[idx].as_mv.row +
mi->bmi[3].as_mv[idx].as_mv.row),
round_mv_comp_q4(mi->bmi[0].as_mv[idx].as_mv.col +
mi->bmi[1].as_mv[idx].as_mv.col +
mi->bmi[2].as_mv[idx].as_mv.col +
mi->bmi[3].as_mv[idx].as_mv.col) };
return res;
}
static INLINE int round_mv_comp_q2(int value) {
return (value < 0 ? value - 1 : value + 1) / 2;
}
static MV mi_mv_pred_q2(const MODE_INFO *mi, int idx, int block0, int block1) {
MV res = { round_mv_comp_q2(mi->bmi[block0].as_mv[idx].as_mv.row +
mi->bmi[block1].as_mv[idx].as_mv.row),
round_mv_comp_q2(mi->bmi[block0].as_mv[idx].as_mv.col +
mi->bmi[block1].as_mv[idx].as_mv.col) };
return res;
}
// TODO(jkoleszar): yet another mv clamping function :-(
MV clamp_mv_to_umv_border_sb(const MACROBLOCKD *xd, const MV *src_mv,
int bw, int bh, int ss_x, int ss_y) {
// If the MV points so far into the UMV border that no visible pixels
// are used for reconstruction, the subpel part of the MV can be
// discarded and the MV limited to 16 pixels with equivalent results.
const int spel_left = (VP9_INTERP_EXTEND + bw) << SUBPEL_BITS;
const int spel_right = spel_left - SUBPEL_SHIFTS;
const int spel_top = (VP9_INTERP_EXTEND + bh) << SUBPEL_BITS;
const int spel_bottom = spel_top - SUBPEL_SHIFTS;
MV clamped_mv = {
src_mv->row * (1 << (1 - ss_y)),
src_mv->col * (1 << (1 - ss_x))
};
assert(ss_x <= 1);
assert(ss_y <= 1);
clamp_mv(&clamped_mv,
xd->mb_to_left_edge * (1 << (1 - ss_x)) - spel_left,
xd->mb_to_right_edge * (1 << (1 - ss_x)) + spel_right,
xd->mb_to_top_edge * (1 << (1 - ss_y)) - spel_top,
xd->mb_to_bottom_edge * (1 << (1 - ss_y)) + spel_bottom);
return clamped_mv;
}
static MV average_split_mvs(const struct macroblockd_plane *pd,
const MODE_INFO *mi, int ref, int block) {
const int ss_idx = ((pd->subsampling_x > 0) << 1) | (pd->subsampling_y > 0);
MV res = {0, 0};
switch (ss_idx) {
case 0:
res = mi->bmi[block].as_mv[ref].as_mv;
break;
case 1:
res = mi_mv_pred_q2(mi, ref, block, block + 2);
break;
case 2:
res = mi_mv_pred_q2(mi, ref, block, block + 1);
break;
case 3:
res = mi_mv_pred_q4(mi, ref);
break;
default:
assert(ss_idx <= 3 || ss_idx >= 0);
}
return res;
}
static void build_inter_predictors(MACROBLOCKD *xd, int plane, int block,
int bw, int bh,
int x, int y, int w, int h,
int mi_x, int mi_y) {
struct macroblockd_plane *const pd = &xd->plane[plane];
const MODE_INFO *mi = xd->mi[0].src_mi;
const int is_compound = has_second_ref(&mi->mbmi);
const InterpKernel *kernel = vp9_get_interp_kernel(mi->mbmi.interp_filter);
int ref;
for (ref = 0; ref < 1 + is_compound; ++ref) {
const struct scale_factors *const sf = &xd->block_refs[ref]->sf;
struct buf_2d *const pre_buf = &pd->pre[ref];
struct buf_2d *const dst_buf = &pd->dst;
uint8_t *const dst = dst_buf->buf + dst_buf->stride * y + x;
const MV mv = mi->mbmi.sb_type < BLOCK_8X8
? average_split_mvs(pd, mi, ref, block)
: mi->mbmi.mv[ref].as_mv;
// TODO(jkoleszar): This clamping is done in the incorrect place for the
// scaling case. It needs to be done on the scaled MV, not the pre-scaling
// MV. Note however that it performs the subsampling aware scaling so
// that the result is always q4.
// mv_precision precision is MV_PRECISION_Q4.
const MV mv_q4 = clamp_mv_to_umv_border_sb(xd, &mv, bw, bh,
pd->subsampling_x,
pd->subsampling_y);
uint8_t *pre;
MV32 scaled_mv;
int xs, ys, subpel_x, subpel_y;
if (vp9_is_scaled(sf)) {
pre = pre_buf->buf + scaled_buffer_offset(x, y, pre_buf->stride, sf);
scaled_mv = vp9_scale_mv(&mv_q4, mi_x + x, mi_y + y, sf);
xs = sf->x_step_q4;
ys = sf->y_step_q4;
} else {
pre = pre_buf->buf + (y * pre_buf->stride + x);
scaled_mv.row = mv_q4.row;
scaled_mv.col = mv_q4.col;
xs = ys = 16;
}
subpel_x = scaled_mv.col & SUBPEL_MASK;
subpel_y = scaled_mv.row & SUBPEL_MASK;
pre += (scaled_mv.row >> SUBPEL_BITS) * pre_buf->stride
+ (scaled_mv.col >> SUBPEL_BITS);
#if CONFIG_VP9_HIGHBITDEPTH
if (xd->cur_buf->flags & YV12_FLAG_HIGHBITDEPTH) {
high_inter_predictor(pre, pre_buf->stride, dst, dst_buf->stride,
subpel_x, subpel_y, sf, w, h, ref, kernel, xs, ys,
xd->bd);
} else {
inter_predictor(pre, pre_buf->stride, dst, dst_buf->stride,
subpel_x, subpel_y, sf, w, h, ref, kernel, xs, ys);
}
#else
inter_predictor(pre, pre_buf->stride, dst, dst_buf->stride,
subpel_x, subpel_y, sf, w, h, ref, kernel, xs, ys);
#endif // CONFIG_VP9_HIGHBITDEPTH
}
}
static void build_inter_predictors_for_planes(MACROBLOCKD *xd, BLOCK_SIZE bsize,
int mi_row, int mi_col,
int plane_from, int plane_to) {
int plane;
const int mi_x = mi_col * MI_SIZE;
const int mi_y = mi_row * MI_SIZE;
for (plane = plane_from; plane <= plane_to; ++plane) {
const BLOCK_SIZE plane_bsize = get_plane_block_size(bsize,
&xd->plane[plane]);
const int num_4x4_w = num_4x4_blocks_wide_lookup[plane_bsize];
const int num_4x4_h = num_4x4_blocks_high_lookup[plane_bsize];
const int bw = 4 * num_4x4_w;
const int bh = 4 * num_4x4_h;
if (xd->mi[0].src_mi->mbmi.sb_type < BLOCK_8X8) {
int i = 0, x, y;
assert(bsize == BLOCK_8X8);
for (y = 0; y < num_4x4_h; ++y)
for (x = 0; x < num_4x4_w; ++x)
build_inter_predictors(xd, plane, i++, bw, bh,
4 * x, 4 * y, 4, 4, mi_x, mi_y);
} else {
build_inter_predictors(xd, plane, 0, bw, bh,
0, 0, bw, bh, mi_x, mi_y);
}
}
}
void vp9_build_inter_predictors_sby(MACROBLOCKD *xd, int mi_row, int mi_col,
BLOCK_SIZE bsize) {
build_inter_predictors_for_planes(xd, bsize, mi_row, mi_col, 0, 0);
}
void vp9_build_inter_predictors_sbuv(MACROBLOCKD *xd, int mi_row, int mi_col,
BLOCK_SIZE bsize) {
build_inter_predictors_for_planes(xd, bsize, mi_row, mi_col, 1,
MAX_MB_PLANE - 1);
}
void vp9_build_inter_predictors_sb(MACROBLOCKD *xd, int mi_row, int mi_col,
BLOCK_SIZE bsize) {
build_inter_predictors_for_planes(xd, bsize, mi_row, mi_col, 0,
MAX_MB_PLANE - 1);
}
// TODO(jingning): This function serves as a placeholder for decoder prediction
// using on demand border extension. It should be moved to /decoder/ directory.
static void dec_build_inter_predictors(MACROBLOCKD *xd, int plane, int block,
int bw, int bh,
int x, int y, int w, int h,
int mi_x, int mi_y) {
struct macroblockd_plane *const pd = &xd->plane[plane];
const MODE_INFO *mi = xd->mi[0].src_mi;
const int is_compound = has_second_ref(&mi->mbmi);
const InterpKernel *kernel = vp9_get_interp_kernel(mi->mbmi.interp_filter);
int ref;
for (ref = 0; ref < 1 + is_compound; ++ref) {
const struct scale_factors *const sf = &xd->block_refs[ref]->sf;
struct buf_2d *const pre_buf = &pd->pre[ref];
struct buf_2d *const dst_buf = &pd->dst;
uint8_t *const dst = dst_buf->buf + dst_buf->stride * y + x;
const MV mv = mi->mbmi.sb_type < BLOCK_8X8
? average_split_mvs(pd, mi, ref, block)
: mi->mbmi.mv[ref].as_mv;
// TODO(jkoleszar): This clamping is done in the incorrect place for the
// scaling case. It needs to be done on the scaled MV, not the pre-scaling
// MV. Note however that it performs the subsampling aware scaling so
// that the result is always q4.
// mv_precision precision is MV_PRECISION_Q4.
const MV mv_q4 = clamp_mv_to_umv_border_sb(xd, &mv, bw, bh,
pd->subsampling_x,
pd->subsampling_y);
MV32 scaled_mv;
int xs, ys, x0, y0, x0_16, y0_16, frame_width, frame_height, buf_stride,
subpel_x, subpel_y;
uint8_t *ref_frame, *buf_ptr;
const YV12_BUFFER_CONFIG *ref_buf = xd->block_refs[ref]->buf;
// Get reference frame pointer, width and height.
if (plane == 0) {
frame_width = ref_buf->y_crop_width;
frame_height = ref_buf->y_crop_height;
ref_frame = ref_buf->y_buffer;
} else {
frame_width = ref_buf->uv_crop_width;
frame_height = ref_buf->uv_crop_height;
ref_frame = plane == 1 ? ref_buf->u_buffer : ref_buf->v_buffer;
}
if (vp9_is_scaled(sf)) {
// Co-ordinate of containing block to pixel precision.
int x_start = (-xd->mb_to_left_edge >> (3 + pd->subsampling_x));
int y_start = (-xd->mb_to_top_edge >> (3 + pd->subsampling_y));
// Co-ordinate of the block to 1/16th pixel precision.
x0_16 = (x_start + x) << SUBPEL_BITS;
y0_16 = (y_start + y) << SUBPEL_BITS;
// Co-ordinate of current block in reference frame
// to 1/16th pixel precision.
x0_16 = sf->scale_value_x(x0_16, sf);
y0_16 = sf->scale_value_y(y0_16, sf);
// Map the top left corner of the block into the reference frame.
x0 = sf->scale_value_x(x_start + x, sf);
y0 = sf->scale_value_y(y_start + y, sf);
// Scale the MV and incorporate the sub-pixel offset of the block
// in the reference frame.
scaled_mv = vp9_scale_mv(&mv_q4, mi_x + x, mi_y + y, sf);
xs = sf->x_step_q4;
ys = sf->y_step_q4;
} else {
// Co-ordinate of containing block to pixel precision.
x0 = (-xd->mb_to_left_edge >> (3 + pd->subsampling_x)) + x;
y0 = (-xd->mb_to_top_edge >> (3 + pd->subsampling_y)) + y;
// Co-ordinate of the block to 1/16th pixel precision.
x0_16 = x0 << SUBPEL_BITS;
y0_16 = y0 << SUBPEL_BITS;
scaled_mv.row = mv_q4.row;
scaled_mv.col = mv_q4.col;
xs = ys = 16;
}
subpel_x = scaled_mv.col & SUBPEL_MASK;
subpel_y = scaled_mv.row & SUBPEL_MASK;
// Calculate the top left corner of the best matching block in the reference frame.
x0 += scaled_mv.col >> SUBPEL_BITS;
y0 += scaled_mv.row >> SUBPEL_BITS;
x0_16 += scaled_mv.col;
y0_16 += scaled_mv.row;
// Get reference block pointer.
buf_ptr = ref_frame + y0 * pre_buf->stride + x0;
buf_stride = pre_buf->stride;
// Do border extension if there is motion or the
// width/height is not a multiple of 8 pixels.
if (scaled_mv.col || scaled_mv.row ||
(frame_width & 0x7) || (frame_height & 0x7)) {
// Get reference block bottom right coordinate.
int x1 = ((x0_16 + (w - 1) * xs) >> SUBPEL_BITS) + 1;
int y1 = ((y0_16 + (h - 1) * ys) >> SUBPEL_BITS) + 1;
int x_pad = 0, y_pad = 0;
if (subpel_x || (sf->x_step_q4 != 16)) {
x0 -= VP9_INTERP_EXTEND - 1;
x1 += VP9_INTERP_EXTEND;
x_pad = 1;
}
if (subpel_y || (sf->y_step_q4 != 16)) {
y0 -= VP9_INTERP_EXTEND - 1;
y1 += VP9_INTERP_EXTEND;
y_pad = 1;
}
// Skip border extension if block is inside the frame.
if (x0 < 0 || x0 > frame_width - 1 || x1 < 0 || x1 > frame_width - 1 ||
y0 < 0 || y0 > frame_height - 1 || y1 < 0 || y1 > frame_height - 1) {
uint8_t *buf_ptr1 = ref_frame + y0 * pre_buf->stride + x0;
// Extend the border.
#if CONFIG_VP9_HIGHBITDEPTH
if (xd->cur_buf->flags & YV12_FLAG_HIGHBITDEPTH) {
high_build_mc_border(buf_ptr1,
pre_buf->stride,
xd->mc_buf_high,
x1 - x0 + 1,
x0,
y0,
x1 - x0 + 1,
y1 - y0 + 1,
frame_width,
frame_height);
buf_stride = x1 - x0 + 1;
buf_ptr = CONVERT_TO_BYTEPTR(xd->mc_buf_high) +
y_pad * 3 * buf_stride + x_pad * 3;
} else {
build_mc_border(buf_ptr1,
pre_buf->stride,
xd->mc_buf,
x1 - x0 + 1,
x0,
y0,
x1 - x0 + 1,
y1 - y0 + 1,
frame_width,
frame_height);
buf_stride = x1 - x0 + 1;
buf_ptr = xd->mc_buf + y_pad * 3 * buf_stride + x_pad * 3;
}
#else
build_mc_border(buf_ptr1,
pre_buf->stride,
xd->mc_buf,
x1 - x0 + 1,
x0,
y0,
x1 - x0 + 1,
y1 - y0 + 1,
frame_width,
frame_height);
buf_stride = x1 - x0 + 1;
buf_ptr = xd->mc_buf + y_pad * 3 * buf_stride + x_pad * 3;
#endif // CONFIG_VP9_HIGHBITDEPTH
}
}
#if CONFIG_VP9_HIGHBITDEPTH
if (xd->cur_buf->flags & YV12_FLAG_HIGHBITDEPTH) {
high_inter_predictor(buf_ptr, buf_stride, dst, dst_buf->stride, subpel_x,
subpel_y, sf, w, h, ref, kernel, xs, ys, xd->bd);
} else {
inter_predictor(buf_ptr, buf_stride, dst, dst_buf->stride, subpel_x,
subpel_y, sf, w, h, ref, kernel, xs, ys);
}
#else
inter_predictor(buf_ptr, buf_stride, dst, dst_buf->stride, subpel_x,
subpel_y, sf, w, h, ref, kernel, xs, ys);
#endif // CONFIG_VP9_HIGHBITDEPTH
}
}
void vp9_dec_build_inter_predictors_sb(MACROBLOCKD *xd, int mi_row, int mi_col,
BLOCK_SIZE bsize) {
int plane;
const int mi_x = mi_col * MI_SIZE;
const int mi_y = mi_row * MI_SIZE;
for (plane = 0; plane < MAX_MB_PLANE; ++plane) {
const BLOCK_SIZE plane_bsize = get_plane_block_size(bsize,
&xd->plane[plane]);
const int num_4x4_w = num_4x4_blocks_wide_lookup[plane_bsize];
const int num_4x4_h = num_4x4_blocks_high_lookup[plane_bsize];
const int bw = 4 * num_4x4_w;
const int bh = 4 * num_4x4_h;
if (xd->mi[0].src_mi->mbmi.sb_type < BLOCK_8X8) {
int i = 0, x, y;
assert(bsize == BLOCK_8X8);
for (y = 0; y < num_4x4_h; ++y)
for (x = 0; x < num_4x4_w; ++x)
dec_build_inter_predictors(xd, plane, i++, bw, bh,
4 * x, 4 * y, 4, 4, mi_x, mi_y);
} else {
dec_build_inter_predictors(xd, plane, 0, bw, bh,
0, 0, bw, bh, mi_x, mi_y);
}
}
}
void vp9_setup_dst_planes(struct macroblockd_plane planes[MAX_MB_PLANE],
const YV12_BUFFER_CONFIG *src,
int mi_row, int mi_col) {
uint8_t *const buffers[4] = {src->y_buffer, src->u_buffer, src->v_buffer,
src->alpha_buffer};
const int strides[4] = {src->y_stride, src->uv_stride, src->uv_stride,
src->alpha_stride};
int i;
for (i = 0; i < MAX_MB_PLANE; ++i) {
struct macroblockd_plane *const pd = &planes[i];
setup_pred_plane(&pd->dst, buffers[i], strides[i], mi_row, mi_col, NULL,
pd->subsampling_x, pd->subsampling_y);
}
}
void vp9_setup_pre_planes(MACROBLOCKD *xd, int idx,
const YV12_BUFFER_CONFIG *src,
int mi_row, int mi_col,
const struct scale_factors *sf) {
if (src != NULL) {
int i;
uint8_t *const buffers[4] = {src->y_buffer, src->u_buffer, src->v_buffer,
src->alpha_buffer};
const int strides[4] = {src->y_stride, src->uv_stride, src->uv_stride,
src->alpha_stride};
for (i = 0; i < MAX_MB_PLANE; ++i) {
struct macroblockd_plane *const pd = &xd->plane[i];
setup_pred_plane(&pd->pre[idx], buffers[i], strides[i], mi_row, mi_col,
sf, pd->subsampling_x, pd->subsampling_y);
}
}
}
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