Palette: modify the context slightly
Use the number of pixels in a block as context, rather than the bsize
itself. The rectangular blocks therefore share the same context, e.g.
BLOCK_8X16 and BLOCK_16X8.
The number of contexts is reduced from 10 to 7.
Almost no coding performance changes.
Change-Id: Ib3241194580c2b93ad0e953957cdc9188393d055
diff --git a/av1/common/entropymode.c b/av1/common/entropymode.c
index 4c664d2..e63bce1 100644
--- a/av1/common/entropymode.c
+++ b/av1/common/entropymode.c
@@ -1139,37 +1139,31 @@
// TODO(huisu): tune these cdfs
const aom_cdf_prob
- default_palette_y_size_cdf[PALETTE_BLOCK_SIZES][CDF_SIZE(PALETTE_SIZES)] = {
+ default_palette_y_size_cdf[PALATTE_BSIZE_CTXS][CDF_SIZE(PALETTE_SIZES)] = {
{ AOM_CDF7(12288, 19408, 24627, 26662, 28499, 30667) },
{ AOM_CDF7(2815, 4570, 9416, 10875, 13782, 19863) },
- { AOM_CDF7(3839, 5986, 11949, 13413, 16286, 21823) },
{ AOM_CDF7(12032, 14948, 22187, 23138, 24756, 27635) },
{ AOM_CDF7(14847, 20167, 25433, 26751, 28278, 30119) },
- { AOM_CDF7(14336, 20240, 24840, 26079, 27908, 30034) },
{ AOM_CDF7(18816, 25574, 29030, 29877, 30656, 31506) },
{ AOM_CDF7(23039, 27333, 30220, 30708, 31070, 31826) },
- { AOM_CDF7(13696, 18911, 23620, 25371, 29821, 31617) },
{ AOM_CDF7(12543, 20838, 27455, 28762, 29763, 31546) },
};
-const aom_cdf_prob default_palette_uv_size_cdf[PALETTE_BLOCK_SIZES][CDF_SIZE(
- PALETTE_SIZES)] = {
- { AOM_CDF7(20480, 29888, 32453, 32715, 32751, 32766) },
- { AOM_CDF7(11135, 23641, 31056, 31998, 32496, 32668) },
- { AOM_CDF7(9216, 23108, 30806, 31871, 32414, 32637) },
- { AOM_CDF7(9984, 21999, 29192, 30645, 31640, 32402) },
- { AOM_CDF7(7552, 16614, 24880, 27283, 29254, 31203) },
- { AOM_CDF7(9600, 20279, 27548, 29261, 30494, 31631) },
- { AOM_CDF7(11391, 18656, 23727, 26058, 27788, 30278) },
- { AOM_CDF7(8576, 13585, 17632, 20884, 23948, 27152) },
- { AOM_CDF7(15360, 24200, 26978, 30846, 31409, 32545) },
- { AOM_CDF7(9216, 14276, 19043, 22689, 25799, 28712) },
-};
+const aom_cdf_prob
+ default_palette_uv_size_cdf[PALATTE_BSIZE_CTXS][CDF_SIZE(PALETTE_SIZES)] = {
+ { AOM_CDF7(20480, 29888, 32453, 32715, 32751, 32766) },
+ { AOM_CDF7(11135, 23641, 31056, 31998, 32496, 32668) },
+ { AOM_CDF7(9984, 21999, 29192, 30645, 31640, 32402) },
+ { AOM_CDF7(7552, 16614, 24880, 27283, 29254, 31203) },
+ { AOM_CDF7(11391, 18656, 23727, 26058, 27788, 30278) },
+ { AOM_CDF7(8576, 13585, 17632, 20884, 23948, 27152) },
+ { AOM_CDF7(9216, 14276, 19043, 22689, 25799, 28712) },
+ };
// When palette mode is enabled, following probability tables indicate the
// probabilities to code the "is_palette" bit (i.e. the bit that indicates
// if this block uses palette mode or DC_PRED mode).
-const aom_cdf_prob default_palette_y_mode_cdf[PALETTE_BLOCK_SIZES]
+const aom_cdf_prob default_palette_y_mode_cdf[PALATTE_BSIZE_CTXS]
[PALETTE_Y_MODE_CONTEXTS]
[CDF_SIZE(2)] = {
{ { AOM_CDF2(128 * 240) },
@@ -1193,15 +1187,6 @@
{ { AOM_CDF2(128 * 240) },
{ AOM_CDF2(128 * 180) },
{ AOM_CDF2(128 * 100) } },
- { { AOM_CDF2(128 * 240) },
- { AOM_CDF2(128 * 180) },
- { AOM_CDF2(128 * 100) } },
- { { AOM_CDF2(128 * 240) },
- { AOM_CDF2(128 * 180) },
- { AOM_CDF2(128 * 100) } },
- { { AOM_CDF2(128 * 240) },
- { AOM_CDF2(128 * 180) },
- { AOM_CDF2(128 * 100) } },
};
const aom_cdf_prob
diff --git a/av1/common/entropymode.h b/av1/common/entropymode.h
index 7665883..fb52ac3 100644
--- a/av1/common/entropymode.h
+++ b/av1/common/entropymode.h
@@ -148,16 +148,15 @@
#endif // CONFIG_EXT_WARPED_MOTION
aom_cdf_prob obmc_cdf[BLOCK_SIZES_ALL][CDF_SIZE(2)];
aom_prob comp_inter_prob[COMP_INTER_CONTEXTS];
- aom_cdf_prob palette_y_size_cdf[PALETTE_BLOCK_SIZES][CDF_SIZE(PALETTE_SIZES)];
- aom_cdf_prob palette_uv_size_cdf[PALETTE_BLOCK_SIZES]
- [CDF_SIZE(PALETTE_SIZES)];
+ aom_cdf_prob palette_y_size_cdf[PALATTE_BSIZE_CTXS][CDF_SIZE(PALETTE_SIZES)];
+ aom_cdf_prob palette_uv_size_cdf[PALATTE_BSIZE_CTXS][CDF_SIZE(PALETTE_SIZES)];
aom_cdf_prob palette_y_color_index_cdf[PALETTE_SIZES]
[PALETTE_COLOR_INDEX_CONTEXTS]
[CDF_SIZE(PALETTE_COLORS)];
aom_cdf_prob palette_uv_color_index_cdf[PALETTE_SIZES]
[PALETTE_COLOR_INDEX_CONTEXTS]
[CDF_SIZE(PALETTE_COLORS)];
- aom_cdf_prob palette_y_mode_cdf[PALETTE_BLOCK_SIZES][PALETTE_Y_MODE_CONTEXTS]
+ aom_cdf_prob palette_y_mode_cdf[PALATTE_BSIZE_CTXS][PALETTE_Y_MODE_CONTEXTS]
[CDF_SIZE(2)];
aom_cdf_prob palette_uv_mode_cdf[PALETTE_UV_MODE_CONTEXTS][CDF_SIZE(2)];
aom_cdf_prob comp_inter_cdf[COMP_INTER_CONTEXTS][CDF_SIZE(2)];
diff --git a/av1/common/enums.h b/av1/common/enums.h
index 04f4b30..a9b2060 100644
--- a/av1/common/enums.h
+++ b/av1/common/enums.h
@@ -70,15 +70,19 @@
#endif
#define MIN_PALETTE_BSIZE BLOCK_8X8
-#define MAX_PALETTE_BSIZE BLOCK_64X64
#define MAX_PALETTE_SQUARE (64 * 64)
+
// Maximum number of colors in a palette.
#define PALETTE_MAX_SIZE 8
// Minimum number of colors in a palette.
#define PALETTE_MIN_SIZE 2
-// Palette mode is available for block sizes between MIN_PALETTE_BSIZE and
-// MAX_PALETTE_BSIZE.
-#define PALETTE_BLOCK_SIZES (MAX_PALETTE_BSIZE - MIN_PALETTE_BSIZE + 1)
+// Map the number of pixels in a block size to a context
+// 64(BLOCK_8X8) -> 0
+// 128(BLOCK_16X8, BLOCK_16X8) -> 1
+// 256(BLOCK_16X16) -> 2
+// ...
+// 4096(BLOCK_64X64) -> 6
+#define PALATTE_BSIZE_CTXS 7
#if CONFIG_FRAME_MARKER
#define FRAME_OFFSET_BITS 5
diff --git a/av1/common/pred_common.h b/av1/common/pred_common.h
index f781987..010f1d4 100644
--- a/av1/common/pred_common.h
+++ b/av1/common/pred_common.h
@@ -184,6 +184,10 @@
int av1_get_palette_cache(const MACROBLOCKD *const xd, int plane,
uint16_t *cache);
+static INLINE int av1_get_palette_bsize_ctx(BLOCK_SIZE bsize) {
+ return num_pels_log2_lookup[bsize] - num_pels_log2_lookup[MIN_PALETTE_BSIZE];
+}
+
int av1_get_intra_inter_context(const MACROBLOCKD *xd);
int av1_get_reference_mode_context(const AV1_COMMON *cm, const MACROBLOCKD *xd);
diff --git a/av1/decoder/decodemv.c b/av1/decoder/decodemv.c
index ed17569..f7e86c7 100644
--- a/av1/decoder/decodemv.c
+++ b/av1/decoder/decodemv.c
@@ -822,7 +822,7 @@
const BLOCK_SIZE bsize = mbmi->sb_type;
assert(av1_allow_palette(cm->allow_screen_content_tools, bsize));
PALETTE_MODE_INFO *const pmi = &mbmi->palette_mode_info;
- const int block_palette_idx = bsize - BLOCK_8X8;
+ const int bsize_ctx = av1_get_palette_bsize_ctx(bsize);
if (mbmi->mode == DC_PRED) {
int palette_y_mode_ctx = 0;
@@ -835,13 +835,11 @@
(left_mi->mbmi.palette_mode_info.palette_size[0] > 0);
}
const int modev = aom_read_symbol(
- r,
- xd->tile_ctx->palette_y_mode_cdf[block_palette_idx][palette_y_mode_ctx],
- 2, ACCT_STR);
+ r, xd->tile_ctx->palette_y_mode_cdf[bsize_ctx][palette_y_mode_ctx], 2,
+ ACCT_STR);
if (modev) {
pmi->palette_size[0] =
- aom_read_symbol(r,
- xd->tile_ctx->palette_y_size_cdf[block_palette_idx],
+ aom_read_symbol(r, xd->tile_ctx->palette_y_size_cdf[bsize_ctx],
PALETTE_SIZES, ACCT_STR) +
2;
read_palette_colors_y(xd, cm->bit_depth, pmi, r);
@@ -853,8 +851,7 @@
r, xd->tile_ctx->palette_uv_mode_cdf[palette_uv_mode_ctx], 2, ACCT_STR);
if (modev) {
pmi->palette_size[1] =
- aom_read_symbol(r,
- xd->tile_ctx->palette_uv_size_cdf[block_palette_idx],
+ aom_read_symbol(r, xd->tile_ctx->palette_uv_size_cdf[bsize_ctx],
PALETTE_SIZES, ACCT_STR) +
2;
read_palette_colors_uv(xd, cm->bit_depth, pmi, r);
diff --git a/av1/encoder/bitstream.c b/av1/encoder/bitstream.c
index 11545ed..db7fd99 100644
--- a/av1/encoder/bitstream.c
+++ b/av1/encoder/bitstream.c
@@ -1023,7 +1023,7 @@
const BLOCK_SIZE bsize = mbmi->sb_type;
assert(av1_allow_palette(cm->allow_screen_content_tools, bsize));
const PALETTE_MODE_INFO *const pmi = &mbmi->palette_mode_info;
- const int block_palette_idx = bsize - BLOCK_8X8;
+ const int bsize_ctx = av1_get_palette_bsize_ctx(bsize);
if (mbmi->mode == DC_PRED) {
const int n = pmi->palette_size[0];
@@ -1038,11 +1038,10 @@
}
aom_write_symbol(
w, n > 0,
- xd->tile_ctx->palette_y_mode_cdf[block_palette_idx][palette_y_mode_ctx],
- 2);
+ xd->tile_ctx->palette_y_mode_cdf[bsize_ctx][palette_y_mode_ctx], 2);
if (n > 0) {
aom_write_symbol(w, n - PALETTE_MIN_SIZE,
- xd->tile_ctx->palette_y_size_cdf[block_palette_idx],
+ xd->tile_ctx->palette_y_size_cdf[bsize_ctx],
PALETTE_SIZES);
write_palette_colors_y(xd, pmi, cm->bit_depth, w);
}
@@ -1060,7 +1059,7 @@
xd->tile_ctx->palette_uv_mode_cdf[palette_uv_mode_ctx], 2);
if (n > 0) {
aom_write_symbol(w, n - PALETTE_MIN_SIZE,
- xd->tile_ctx->palette_uv_size_cdf[block_palette_idx],
+ xd->tile_ctx->palette_uv_size_cdf[bsize_ctx],
PALETTE_SIZES);
write_palette_colors_uv(xd, pmi, cm->bit_depth, w);
}
diff --git a/av1/encoder/block.h b/av1/encoder/block.h
index 4489913..1e83ad6 100644
--- a/av1/encoder/block.h
+++ b/av1/encoder/block.h
@@ -305,13 +305,13 @@
#else
int partition_cost[PARTITION_CONTEXTS][PARTITION_TYPES];
#endif // CONFIG_EXT_PARTITION_TYPES
- int palette_y_size_cost[PALETTE_BLOCK_SIZES][PALETTE_SIZES];
- int palette_uv_size_cost[PALETTE_BLOCK_SIZES][PALETTE_SIZES];
+ int palette_y_size_cost[PALATTE_BSIZE_CTXS][PALETTE_SIZES];
+ int palette_uv_size_cost[PALATTE_BSIZE_CTXS][PALETTE_SIZES];
int palette_y_color_cost[PALETTE_SIZES][PALETTE_COLOR_INDEX_CONTEXTS]
[PALETTE_COLORS];
int palette_uv_color_cost[PALETTE_SIZES][PALETTE_COLOR_INDEX_CONTEXTS]
[PALETTE_COLORS];
- int palette_y_mode_cost[PALETTE_BLOCK_SIZES][PALETTE_Y_MODE_CONTEXTS][2];
+ int palette_y_mode_cost[PALATTE_BSIZE_CTXS][PALETTE_Y_MODE_CONTEXTS][2];
int palette_uv_mode_cost[PALETTE_UV_MODE_CONTEXTS][2];
#if CONFIG_CFL
// The rate associated with each alpha codeword
diff --git a/av1/encoder/encodeframe.c b/av1/encoder/encodeframe.c
index 635a992..a00b4bd 100644
--- a/av1/encoder/encodeframe.c
+++ b/av1/encoder/encodeframe.c
@@ -4220,7 +4220,7 @@
const PALETTE_MODE_INFO *const pmi = &mbmi->palette_mode_info;
assert(bsize >= BLOCK_8X8 && bsize <= BLOCK_LARGEST);
- const int block_palette_idx = bsize - BLOCK_8X8;
+ const int bsize_ctx = av1_get_palette_bsize_ctx(bsize);
if (mbmi->mode == DC_PRED) {
const int n = pmi->palette_size[0];
@@ -4233,8 +4233,7 @@
palette_y_mode_ctx +=
(left_mi->mbmi.palette_mode_info.palette_size[0] > 0);
}
- update_cdf(fc->palette_y_mode_cdf[block_palette_idx][palette_y_mode_ctx],
- n > 0, 2);
+ update_cdf(fc->palette_y_mode_cdf[bsize_ctx][palette_y_mode_ctx], n > 0, 2);
}
if (mbmi->uv_mode == UV_DC_PRED) {
diff --git a/av1/encoder/rd.c b/av1/encoder/rd.c
index 710df4f..601d1b6 100644
--- a/av1/encoder/rd.c
+++ b/av1/encoder/rd.c
@@ -130,7 +130,7 @@
av1_cost_tokens_from_cdf(x->switchable_interp_costs[i],
fc->switchable_interp_cdf[i], NULL);
- for (i = 0; i < PALETTE_BLOCK_SIZES; ++i) {
+ for (i = 0; i < PALATTE_BSIZE_CTXS; ++i) {
av1_cost_tokens_from_cdf(x->palette_y_size_cost[i],
fc->palette_y_size_cdf[i], NULL);
av1_cost_tokens_from_cdf(x->palette_uv_size_cost[i],
diff --git a/av1/encoder/rdopt.c b/av1/encoder/rdopt.c
index 5e62b17..5e93d53 100644
--- a/av1/encoder/rdopt.c
+++ b/av1/encoder/rdopt.c
@@ -2855,11 +2855,11 @@
&cols);
av1_calc_indices(data, centroids, color_map, rows * cols, k, 1);
extend_palette_color_map(color_map, cols, rows, block_width, block_height);
+ const int bsize_ctx = av1_get_palette_bsize_ctx(bsize);
int palette_mode_cost =
- dc_mode_cost +
- x->palette_y_size_cost[bsize - BLOCK_8X8][k - PALETTE_MIN_SIZE] +
+ dc_mode_cost + x->palette_y_size_cost[bsize_ctx][k - PALETTE_MIN_SIZE] +
write_uniform_cost(k, color_map[0]) +
- x->palette_y_mode_cost[bsize - BLOCK_8X8][palette_ctx][1];
+ x->palette_y_mode_cost[bsize_ctx][palette_ctx][1];
palette_mode_cost += av1_palette_color_cost_y(pmi, color_cache, n_cache,
cpi->common.bit_depth);
palette_mode_cost +=
@@ -3491,8 +3491,8 @@
tx_size_cost(&cpi->common, x, bsize, mbmi->tx_size);
}
if (try_palette && mbmi->mode == DC_PRED) {
- this_rate +=
- x->palette_y_mode_cost[bsize - BLOCK_8X8][palette_y_mode_ctx][0];
+ const int bsize_ctx = av1_get_palette_bsize_ctx(bsize);
+ this_rate += x->palette_y_mode_cost[bsize_ctx][palette_y_mode_ctx][0];
}
#if CONFIG_FILTER_INTRA
if (mbmi->mode == DC_PRED && av1_filter_intra_allowed_txsize(mbmi->tx_size))
@@ -5251,11 +5251,11 @@
super_block_uvrd(cpi, x, &tokenonly_rd_stats, bsize, *best_rd);
if (tokenonly_rd_stats.rate == INT_MAX) continue;
- this_rate =
- tokenonly_rd_stats.rate + dc_mode_cost +
- x->palette_uv_size_cost[bsize - BLOCK_8X8][n - PALETTE_MIN_SIZE] +
- write_uniform_cost(n, color_map[0]) +
- x->palette_uv_mode_cost[pmi->palette_size[0] > 0][1];
+ const int bsize_ctx = av1_get_palette_bsize_ctx(bsize);
+ this_rate = tokenonly_rd_stats.rate + dc_mode_cost +
+ x->palette_uv_size_cost[bsize_ctx][n - PALETTE_MIN_SIZE] +
+ write_uniform_cost(n, color_map[0]) +
+ x->palette_uv_mode_cost[pmi->palette_size[0] > 0][1];
this_rate += av1_palette_color_cost_uv(pmi, color_cache, n_cache,
cpi->common.bit_depth);
this_rate += av1_cost_color_map(x, 1, bsize, mbmi->tx_size, PALETTE_MAP);
@@ -9888,7 +9888,8 @@
rate2 += rate_uv + x->intra_uv_mode_cost[mbmi->mode][mbmi->uv_mode];
if (try_palette && mbmi->mode == DC_PRED) {
- rate2 += x->palette_y_mode_cost[bsize - BLOCK_8X8][palette_ctx][0];
+ const int bsize_ctx = av1_get_palette_bsize_ctx(bsize);
+ rate2 += x->palette_y_mode_cost[bsize_ctx][palette_ctx][0];
}
if (!xd->lossless[mbmi->segment_id] && block_signals_txsize(bsize)) {
