Replace 'cdef_preset' with bool 'cdef_transmitted'
The original array 'cdef_preset' in MACROBLOCKD was an integer array,
but was only used to check if it is initialized on not. However, it was
not trivial to understand that from the original code.
So, 'read_cdef' and 'write_cdef' were simplified and rewritten to make
this logic clear.
Also, added detailed documentation for the new array 'cdef_transmitted'.
BUG=aomedia:2610
Change-Id: I5dc3b1dd51b6520882498acff09b1003176b2c56
diff --git a/av1/common/blockd.h b/av1/common/blockd.h
index 0f2a241..47597bc 100644
--- a/av1/common/blockd.h
+++ b/av1/common/blockd.h
@@ -644,7 +644,20 @@
// SEG_LVL_ALT_LF_U = 3;
// SEG_LVL_ALT_LF_V = 4;
int8_t delta_lf[FRAME_LF_COUNT];
- int cdef_preset[4];
+ // cdef_transmitted[i] is true if CDEF strength for ith CDEF unit in the
+ // current superblock has already been read from (decoder) / written to
+ // (encoder) the bitstream; and false otherwise.
+ // More detail:
+ // (1) CDEF strength is transmitted only once per CDEF unit, in the 1st
+ // non-skip coding block. So, we need this array to keep track of whether CDEF
+ // strengths for the given CDEF units have been transmitted yet or not.
+ // (2) Superblock size can be either 128x128 or 64x64, but CDEF unit size is
+ // fixed to be 64x64. So, there may be 4 CDEF units within a superblock (if
+ // superblock size is 128x128). Hence the array size is 4.
+ // (3) In the current implementation, CDEF strength for this CDEF unit is
+ // stored in the MB_MODE_INFO of the 1st block in this CDEF unit (inside
+ // cm->mi_params.mi_grid_base).
+ bool cdef_transmitted[4];
DECLARE_ALIGNED(16, uint8_t, seg_mask[2 * MAX_SB_SQUARE]);
uint8_t *mc_buf[2];
diff --git a/av1/decoder/decodemv.c b/av1/decoder/decodemv.c
index d47868f..e97cec4 100644
--- a/av1/decoder/decodemv.c
+++ b/av1/decoder/decodemv.c
@@ -37,32 +37,48 @@
}
static void read_cdef(AV1_COMMON *cm, aom_reader *r, MACROBLOCKD *const xd) {
- MB_MODE_INFO *const mbmi = xd->mi[0];
+ const int skip = xd->mi[0]->skip;
if (cm->features.coded_lossless) return;
if (cm->features.allow_intrabc) {
assert(cm->cdef_info.cdef_bits == 0);
return;
}
- const int mi_row = xd->mi_row;
- const int mi_col = xd->mi_col;
- if (!(mi_col & (cm->seq_params.mib_size - 1)) &&
- !(mi_row & (cm->seq_params.mib_size - 1))) { // Top left?
- xd->cdef_preset[0] = xd->cdef_preset[1] = xd->cdef_preset[2] =
- xd->cdef_preset[3] = -1;
+ // At the start of a superblock, mark that we haven't yet read CDEF strengths
+ // for any of the CDEF units contained in this superblock.
+ const int sb_mask = (cm->seq_params.mib_size - 1);
+ const int mi_row_in_sb = (xd->mi_row & sb_mask);
+ const int mi_col_in_sb = (xd->mi_col & sb_mask);
+ if (mi_row_in_sb == 0 && mi_col_in_sb == 0) {
+ xd->cdef_transmitted[0] = xd->cdef_transmitted[1] =
+ xd->cdef_transmitted[2] = xd->cdef_transmitted[3] = false;
}
- // Read CDEF param at the first non-skip coding block
- const int mask = (1 << (6 - MI_SIZE_LOG2));
- const int m = ~(mask - 1);
- const int index = cm->seq_params.sb_size == BLOCK_128X128
- ? !!(mi_col & mask) + 2 * !!(mi_row & mask)
+
+ // CDEF unit size is 64x64 irrespective of the superblock size.
+ const int cdef_size = 1 << (6 - MI_SIZE_LOG2);
+
+ // Find index of this CDEF unit in this superblock.
+ const int index_mask = cdef_size;
+ const int cdef_unit_row_in_sb = ((xd->mi_row & index_mask) != 0);
+ const int cdef_unit_col_in_sb = ((xd->mi_col & index_mask) != 0);
+ const int index = (cm->seq_params.sb_size == BLOCK_128X128)
+ ? cdef_unit_col_in_sb + 2 * cdef_unit_row_in_sb
: 0;
- cm->mi_params
- .mi_grid_base[(mi_row & m) * cm->mi_params.mi_stride + (mi_col & m)]
- ->cdef_strength = xd->cdef_preset[index] =
- xd->cdef_preset[index] == -1 && !mbmi->skip
- ? aom_read_literal(r, cm->cdef_info.cdef_bits, ACCT_STR)
- : xd->cdef_preset[index];
+
+ // Read CDEF strength from the first non-skip coding block in this CDEF unit.
+ if (!xd->cdef_transmitted[index] && !skip) {
+ // CDEF strength for this CDEF unit needs to be read into the MB_MODE_INFO
+ // of the 1st block in this CDEF unit.
+ const int first_block_mask = ~(cdef_size - 1);
+ CommonModeInfoParams *const mi_params = &cm->mi_params;
+ const int grid_idx =
+ get_mi_grid_idx(mi_params, xd->mi_row & first_block_mask,
+ xd->mi_col & first_block_mask);
+ MB_MODE_INFO *const mbmi = mi_params->mi_grid_base[grid_idx];
+ mbmi->cdef_strength =
+ aom_read_literal(r, cm->cdef_info.cdef_bits, ACCT_STR);
+ xd->cdef_transmitted[index] = true;
+ }
}
static int read_delta_qindex(AV1_COMMON *cm, const MACROBLOCKD *xd,
diff --git a/av1/encoder/bitstream.c b/av1/encoder/bitstream.c
index 9929995..805a112 100644
--- a/av1/encoder/bitstream.c
+++ b/av1/encoder/bitstream.c
@@ -863,27 +863,39 @@
aom_writer *w, int skip) {
if (cm->features.coded_lossless || cm->features.allow_intrabc) return;
- const int m = ~((1 << (6 - MI_SIZE_LOG2)) - 1);
- const int mi_row = xd->mi_row;
- const int mi_col = xd->mi_col;
- const MB_MODE_INFO *mbmi =
- cm->mi_params
- .mi_grid_base[(mi_row & m) * cm->mi_params.mi_stride + (mi_col & m)];
- // Initialise when at top left part of the superblock
- if (!(mi_row & (cm->seq_params.mib_size - 1)) &&
- !(mi_col & (cm->seq_params.mib_size - 1))) { // Top left?
- xd->cdef_preset[0] = xd->cdef_preset[1] = xd->cdef_preset[2] =
- xd->cdef_preset[3] = -1;
+ // At the start of a superblock, mark that we haven't yet written CDEF
+ // strengths for any of the CDEF units contained in this superblock.
+ const int sb_mask = (cm->seq_params.mib_size - 1);
+ const int mi_row_in_sb = (xd->mi_row & sb_mask);
+ const int mi_col_in_sb = (xd->mi_col & sb_mask);
+ if (mi_row_in_sb == 0 && mi_col_in_sb == 0) {
+ xd->cdef_transmitted[0] = xd->cdef_transmitted[1] =
+ xd->cdef_transmitted[2] = xd->cdef_transmitted[3] = false;
}
- // Emit CDEF param at first non-skip coding block
- const int mask = 1 << (6 - MI_SIZE_LOG2);
- const int index = cm->seq_params.sb_size == BLOCK_128X128
- ? !!(mi_col & mask) + 2 * !!(mi_row & mask)
+ // CDEF unit size is 64x64 irrespective of the superblock size.
+ const int cdef_size = 1 << (6 - MI_SIZE_LOG2);
+
+ // Find index of this CDEF unit in this superblock.
+ const int index_mask = cdef_size;
+ const int cdef_unit_row_in_sb = ((xd->mi_row & index_mask) != 0);
+ const int cdef_unit_col_in_sb = ((xd->mi_col & index_mask) != 0);
+ const int index = (cm->seq_params.sb_size == BLOCK_128X128)
+ ? cdef_unit_col_in_sb + 2 * cdef_unit_row_in_sb
: 0;
- if (xd->cdef_preset[index] == -1 && !skip) {
+
+ // Write CDEF strength to the first non-skip coding block in this CDEF unit.
+ if (!xd->cdef_transmitted[index] && !skip) {
+ // CDEF strength for this CDEF unit needs to be stored in the MB_MODE_INFO
+ // of the 1st block in this CDEF unit.
+ const int first_block_mask = ~(cdef_size - 1);
+ const CommonModeInfoParams *const mi_params = &cm->mi_params;
+ const int grid_idx =
+ get_mi_grid_idx(mi_params, xd->mi_row & first_block_mask,
+ xd->mi_col & first_block_mask);
+ const MB_MODE_INFO *const mbmi = mi_params->mi_grid_base[grid_idx];
aom_write_literal(w, mbmi->cdef_strength, cm->cdef_info.cdef_bits);
- xd->cdef_preset[index] = mbmi->cdef_strength;
+ xd->cdef_transmitted[index] = true;
}
}
