ref: 1d6f9305175ea1ad902a49ef527f11a46902de7d
dir: /vp9/common/vp9_blockd.c/
/*
* Copyright (c) 2014 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 "vp9/common/vp9_blockd.h"
PREDICTION_MODE vp9_left_block_mode(const MODE_INFO *cur_mi,
const MODE_INFO *left_mi, int b) {
if (b == 0 || b == 2) {
if (!left_mi || is_inter_block(left_mi)) return DC_PRED;
return get_y_mode(left_mi, b + 1);
} else {
assert(b == 1 || b == 3);
return cur_mi->bmi[b - 1].as_mode;
}
}
PREDICTION_MODE vp9_above_block_mode(const MODE_INFO *cur_mi,
const MODE_INFO *above_mi, int b) {
if (b == 0 || b == 1) {
if (!above_mi || is_inter_block(above_mi)) return DC_PRED;
return get_y_mode(above_mi, b + 2);
} else {
assert(b == 2 || b == 3);
return cur_mi->bmi[b - 2].as_mode;
}
}
void vp9_foreach_transformed_block_in_plane(
const MACROBLOCKD *const xd, BLOCK_SIZE bsize, int plane,
foreach_transformed_block_visitor visit, void *arg) {
const struct macroblockd_plane *const pd = &xd->plane[plane];
const MODE_INFO *mi = xd->mi[0];
// block and transform sizes, in number of 4x4 blocks log 2 ("*_b")
// 4x4=0, 8x8=2, 16x16=4, 32x32=6, 64x64=8
// transform size varies per plane, look it up in a common way.
const TX_SIZE tx_size = plane ? get_uv_tx_size(mi, pd) : mi->tx_size;
const BLOCK_SIZE plane_bsize = get_plane_block_size(bsize, pd);
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 step = 1 << (tx_size << 1);
int i = 0, r, c;
// If mb_to_right_edge is < 0 we are in a situation in which
// the current block size extends into the UMV and we won't
// visit the sub blocks that are wholly within the UMV.
const int max_blocks_wide =
num_4x4_w + (xd->mb_to_right_edge >= 0
? 0
: xd->mb_to_right_edge >> (5 + pd->subsampling_x));
const int max_blocks_high =
num_4x4_h + (xd->mb_to_bottom_edge >= 0
? 0
: xd->mb_to_bottom_edge >> (5 + pd->subsampling_y));
const int extra_step = ((num_4x4_w - max_blocks_wide) >> tx_size) * step;
// Keep track of the row and column of the blocks we use so that we know
// if we are in the unrestricted motion border.
for (r = 0; r < max_blocks_high; r += (1 << tx_size)) {
// Skip visiting the sub blocks that are wholly within the UMV.
for (c = 0; c < max_blocks_wide; c += (1 << tx_size)) {
visit(plane, i, r, c, plane_bsize, tx_size, arg);
i += step;
}
i += extra_step;
}
}
void vp9_foreach_transformed_block(const MACROBLOCKD *const xd,
BLOCK_SIZE bsize,
foreach_transformed_block_visitor visit,
void *arg) {
int plane;
for (plane = 0; plane < MAX_MB_PLANE; ++plane)
vp9_foreach_transformed_block_in_plane(xd, bsize, plane, visit, arg);
}
void vp9_set_contexts(const MACROBLOCKD *xd, struct macroblockd_plane *pd,
BLOCK_SIZE plane_bsize, TX_SIZE tx_size, int has_eob,
int aoff, int loff) {
ENTROPY_CONTEXT *const a = pd->above_context + aoff;
ENTROPY_CONTEXT *const l = pd->left_context + loff;
const int tx_size_in_blocks = 1 << tx_size;
// above
if (has_eob && xd->mb_to_right_edge < 0) {
int i;
const int blocks_wide = num_4x4_blocks_wide_lookup[plane_bsize] +
(xd->mb_to_right_edge >> (5 + pd->subsampling_x));
int above_contexts = tx_size_in_blocks;
if (above_contexts + aoff > blocks_wide)
above_contexts = blocks_wide - aoff;
for (i = 0; i < above_contexts; ++i) a[i] = has_eob;
for (i = above_contexts; i < tx_size_in_blocks; ++i) a[i] = 0;
} else {
memset(a, has_eob, sizeof(ENTROPY_CONTEXT) * tx_size_in_blocks);
}
// left
if (has_eob && xd->mb_to_bottom_edge < 0) {
int i;
const int blocks_high = num_4x4_blocks_high_lookup[plane_bsize] +
(xd->mb_to_bottom_edge >> (5 + pd->subsampling_y));
int left_contexts = tx_size_in_blocks;
if (left_contexts + loff > blocks_high) left_contexts = blocks_high - loff;
for (i = 0; i < left_contexts; ++i) l[i] = has_eob;
for (i = left_contexts; i < tx_size_in_blocks; ++i) l[i] = 0;
} else {
memset(l, has_eob, sizeof(ENTROPY_CONTEXT) * tx_size_in_blocks);
}
}
void vp9_setup_block_planes(MACROBLOCKD *xd, int ss_x, int ss_y) {
int i;
for (i = 0; i < MAX_MB_PLANE; i++) {
xd->plane[i].subsampling_x = i ? ss_x : 0;
xd->plane[i].subsampling_y = i ? ss_y : 0;
}
}