[CFL] Load luma as prediction for chroma
Loads the stored reconstructed luma pixels for each trasnform block
inside a prediction block. Supports 4:4:4 and 4:2:0 chroma subsampling
modes.
The CFL_CTX struct is now in cfl.h with appropriate forward declarations
Change-Id: I44c117899414a10a8318d14ecaed402f803de97d
diff --git a/av1/common/blockd.h b/av1/common/blockd.h
index 8b80332..c53a3ff 100644
--- a/av1/common/blockd.h
+++ b/av1/common/blockd.h
@@ -31,7 +31,9 @@
#include "av1/common/pvq_state.h"
#include "av1/decoder/decint.h"
#endif
-
+#if CONFIG_CFL
+#include "av1/common/cfl.h"
+#endif
#ifdef __cplusplus
extern "C" {
#endif
@@ -552,19 +554,6 @@
typedef int16_t EobThresholdMD[TX_SIZES_ALL][TX_TYPES];
-#if CONFIG_CFL
-typedef struct {
- // Pixel buffer containing the luma pixels used as prediction for chroma
- uint8_t y_pix[MAX_SB_SQUARE];
-
- // Height and width of the luma prediction block currently in the pixel buffer
- int y_height, y_width;
-
- // CfL Performs its own block level DC_PRED for each chromatic plane
- int dc_pred[CFL_PRED_PLANES];
-} CFL_CTX;
-#endif
-
typedef struct macroblockd {
struct macroblockd_plane plane[MAX_MB_PLANE];
uint8_t bmode_blocks_wl;
diff --git a/av1/common/cfl.c b/av1/common/cfl.c
index 53e117e..b49890e 100644
--- a/av1/common/cfl.c
+++ b/av1/common/cfl.c
@@ -11,6 +11,21 @@
#include "av1/common/cfl.h"
#include "av1/common/common_data.h"
+#include "av1/common/onyxc_int.h"
+
+#include "aom/internal/aom_codec_internal.h"
+
+void cfl_init(CFL_CTX *cfl, AV1_COMMON *cm, int subsampling_x,
+ int subsampling_y) {
+ if (!((subsampling_x == 0 && subsampling_y == 0) ||
+ (subsampling_x == 1 && subsampling_y == 1))) {
+ aom_internal_error(&cm->error, AOM_CODEC_UNSUP_BITSTREAM,
+ "Only 4:4:4 and 4:2:0 are currently supported by CfL");
+ }
+ memset(&cfl->y_pix, 0, sizeof(uint8_t) * MAX_SB_SQUARE);
+ cfl->subsampling_x = subsampling_x;
+ cfl->subsampling_y = subsampling_y;
+}
// CfL computes its own block-level DC_PRED. This is required to compute both
// alpha_cb and alpha_cr before the prediction are computed.
@@ -72,14 +87,19 @@
// Predict the current transform block using CfL.
// it is assumed that dst points at the start of the transform block
-void cfl_predict_block(uint8_t *dst, int dst_stride, TX_SIZE tx_size,
- int dc_pred) {
+void cfl_predict_block(const CFL_CTX *cfl, uint8_t *dst, int dst_stride,
+ int row, int col, TX_SIZE tx_size, int dc_pred) {
const int tx_block_width = tx_size_wide[tx_size];
const int tx_block_height = tx_size_high[tx_size];
+ // TODO(ltrudeau) implement alpha
+ // Place holder for alpha
+ const double alpha = 0;
+ const double y_avg = cfl_load(cfl, dst, dst_stride, row, col, tx_size);
+
for (int j = 0; j < tx_block_height; j++) {
for (int i = 0; i < tx_block_width; i++) {
- dst[i] = dc_pred;
+ dst[i] = (uint8_t)(alpha * y_avg + dc_pred + 0.5);
}
dst += dst_stride;
}
@@ -117,3 +137,102 @@
cfl->y_height = OD_MAXI((row << tx_off_log2) + tx_height, cfl->y_height);
}
}
+
+// Load from the CfL pixel buffer into output
+double cfl_load(const CFL_CTX *cfl, uint8_t *output, int output_stride, int row,
+ int col, TX_SIZE tx_size) {
+ const int tx_width = tx_size_wide[tx_size];
+ const int tx_height = tx_size_high[tx_size];
+ const int sub_x = cfl->subsampling_x;
+ const int sub_y = cfl->subsampling_y;
+ const int tx_off_log2 = tx_size_wide_log2[0];
+
+ const uint8_t *y_pix;
+
+ int diff_width = 0;
+ int diff_height = 0;
+
+ int pred_row_offset = 0;
+ int output_row_offset = 0;
+ int top_left, bot_left;
+
+ // TODO(ltrudeau) add support for 4:2:2
+ if (sub_y == 0 && sub_x == 0) {
+ y_pix = &cfl->y_pix[(row * MAX_SB_SIZE + col) << tx_off_log2];
+ int uv_width = (col << tx_off_log2) + tx_width;
+ diff_width = uv_width - cfl->y_width;
+ int uv_height = (row << tx_off_log2) + tx_width;
+ diff_height = uv_height - cfl->y_height;
+ for (int j = 0; j < tx_height; j++) {
+ for (int i = 0; i < tx_width; i++) {
+ // In 4:4:4, pixels match 1 to 1
+ output[output_row_offset + i] = y_pix[pred_row_offset + i];
+ }
+ pred_row_offset += MAX_SB_SIZE;
+ output_row_offset += output_stride;
+ }
+ } else if (sub_y == 1 && sub_x == 1) {
+ y_pix = &cfl->y_pix[(row * MAX_SB_SIZE + col) << (tx_off_log2 + sub_y)];
+ int uv_width = ((col << tx_off_log2) + tx_width) << sub_x;
+ diff_width = (uv_width - cfl->y_width) >> sub_x;
+ int uv_height = ((row << tx_off_log2) + tx_width) << sub_y;
+ diff_height = (uv_height - cfl->y_height) >> sub_y;
+ for (int j = 0; j < tx_height; j++) {
+ for (int i = 0; i < tx_width; i++) {
+ top_left = (pred_row_offset + i) << sub_y;
+ bot_left = top_left + MAX_SB_SIZE;
+ // In 4:2:0, average pixels in 2x2 grid
+ output[output_row_offset + i] = OD_SHR_ROUND(
+ y_pix[top_left] + y_pix[top_left + 1] // Top row
+ + y_pix[bot_left] + y_pix[bot_left + 1] // Bottom row
+ ,
+ 2);
+ }
+ pred_row_offset += MAX_SB_SIZE;
+ output_row_offset += output_stride;
+ }
+ } else {
+ assert(0); // Unsupported chroma subsampling
+ }
+ // Due to frame boundary issues, it is possible that the total area of
+ // covered by Chroma exceeds that of Luma. When this happens, we write over
+ // the broken data by repeating the last columns and/or rows.
+ //
+ // Note that in order to manage the case where both rows and columns
+ // overrun,
+ // we apply rows first. This way, when the rows overrun the bottom of the
+ // frame, the columns will be copied over them.
+ if (diff_width > 0) {
+ int last_pixel;
+ output_row_offset = tx_width - diff_width;
+
+ for (int j = 0; j < tx_height; j++) {
+ last_pixel = output_row_offset - 1;
+ for (int i = 0; i < diff_width; i++) {
+ output[output_row_offset + i] = output[last_pixel];
+ }
+ output_row_offset += output_stride;
+ }
+ }
+
+ if (diff_height > 0) {
+ output_row_offset = diff_height * output_stride;
+ const int last_row_offset = output_row_offset - output_stride;
+ for (int j = 0; j < diff_height; j++) {
+ for (int i = 0; i < tx_width; i++) {
+ output[output_row_offset + i] = output[last_row_offset + i];
+ }
+ output_row_offset += output_stride;
+ }
+ }
+
+ int avg = 0;
+ output_row_offset = 0;
+ for (int j = 0; j < tx_height; j++) {
+ for (int i = 0; i < tx_width; i++) {
+ avg += output[output_row_offset + i];
+ }
+ output_row_offset += output_stride;
+ }
+ return avg / (double)(tx_width * tx_height);
+}
diff --git a/av1/common/cfl.h b/av1/common/cfl.h
index 3edcb0f..371df70 100644
--- a/av1/common/cfl.h
+++ b/av1/common/cfl.h
@@ -12,15 +12,41 @@
#ifndef AV1_COMMON_CFL_H_
#define AV1_COMMON_CFL_H_
-#include "av1/common/blockd.h"
#include "av1/common/enums.h"
+// Forward declaration of AV1_COMMON, in order to avoid creating a cyclic
+// dependency by importing av1/common/onyxc_int.h
+typedef struct AV1Common AV1_COMMON;
+
+// Forward declaration of MACROBLOCK, in order to avoid creating a cyclic
+// dependency by importing av1/common/blockd.h
+typedef struct macroblockd MACROBLOCKD;
+
+typedef struct {
+ // Pixel buffer containing the luma pixels used as prediction for chroma
+ uint8_t y_pix[MAX_SB_SQUARE];
+
+ // Height and width of the luma prediction block currently in the pixel buffer
+ int y_height, y_width;
+
+ // Chroma subsampling
+ int subsampling_x, subsampling_y;
+
+ // CfL Performs its own block level DC_PRED for each chromatic plane
+ int dc_pred[CFL_PRED_PLANES];
+} CFL_CTX;
+
+void cfl_init(CFL_CTX *cfl, AV1_COMMON *cm, int subsampling_x,
+ int subsampling_y);
+
void cfl_dc_pred(MACROBLOCKD *xd, BLOCK_SIZE plane_bsize, TX_SIZE tx_size);
-void cfl_predict_block(uint8_t *dst, int dst_stride, TX_SIZE tx_size,
- int dc_pred);
+void cfl_predict_block(const CFL_CTX *cfl, uint8_t *dst, int dst_stride,
+ int row, int col, TX_SIZE tx_size, int dc_pred);
void cfl_store(CFL_CTX *cfl, const uint8_t *input, int input_stride, int row,
int col, TX_SIZE tx_size);
+double cfl_load(const CFL_CTX *cfl, uint8_t *output, int output_stride, int row,
+ int col, TX_SIZE tx_size);
#endif // AV1_COMMON_CFL_H_
diff --git a/av1/common/onyxc_int.h b/av1/common/onyxc_int.h
index de52359..53a3800 100644
--- a/av1/common/onyxc_int.h
+++ b/av1/common/onyxc_int.h
@@ -35,6 +35,9 @@
#if CONFIG_PVQ
#include "av1/common/pvq.h"
#endif
+#if CONFIG_CFL
+#include "av1/common/cfl.h"
+#endif
#ifdef __cplusplus
extern "C" {
#endif
@@ -535,7 +538,8 @@
#endif
#if CONFIG_CFL
xd->cfl = cfl;
- memset(&cfl->y_pix, 0, sizeof(uint8_t) * MAX_SB_SQUARE);
+ cfl_init(cfl, cm, xd->plane[AOM_PLANE_U].subsampling_x,
+ xd->plane[AOM_PLANE_U].subsampling_y);
#endif
xd->above_context[i] = cm->above_context[i];
if (xd->plane[i].plane_type == PLANE_TYPE_Y) {
diff --git a/av1/common/reconintra.c b/av1/common/reconintra.c
index 5477d6d..3d98895 100644
--- a/av1/common/reconintra.c
+++ b/av1/common/reconintra.c
@@ -2308,7 +2308,7 @@
// is signaled.
cfl_dc_pred(xd, get_plane_block_size(block_idx, pd), tx_size);
}
- cfl_predict_block(dst, pd->dst.stride, tx_size,
+ cfl_predict_block(xd->cfl, dst, pd->dst.stride, blk_row, blk_col, tx_size,
xd->cfl->dc_pred[plane - 1]);
}
#endif
