ref: 7e234b92286fbf96be601f2ff239a7afe2f6c09b
parent: 9a1ce7be7d4a3056b9da1df64cb7d5115a513dd9
author: paulwilkins <paulwilkins@google.com>
date: Wed Mar 18 10:41:18 EDT 2015
Revised rd adjustment for variance. Revised adjustment for rd based on source complexity. Two cases: 1) Bias against low variance intra predictors when the actual source variance is higher. 2) When the source variance is very low to give a slight bias against predictors that might introduce false texture or features. The impact on metrics of this change across the test sets is small and mixed. derf -0.073%, -0.049%, -0.291% std hd -0.093%, -0.1%, -0.557% yt +0.186%, +0.04%, - 0.074% ythd +0.625%, + 0.563%, +0.584% Medium to strong psycho-visual improvements in some problem clips. This feature and intra weight on GF group length now turned on by default. Change-Id: Idefc8b633a7b7bc56c42dbe19f6b2f872d73851e
--- a/vp9/encoder/vp9_firstpass.c
+++ b/vp9/encoder/vp9_firstpass.c
@@ -61,12 +61,9 @@
#define RC_FACTOR_MAX 1.75
-#define INTRA_WEIGHT_EXPERIMENT 0
-#if INTRA_WEIGHT_EXPERIMENT
#define NCOUNT_INTRA_THRESH 8192
#define NCOUNT_INTRA_FACTOR 3
#define NCOUNT_FRAME_II_THRESH 5.0
-#endif
#define DOUBLE_DIVIDE_CHECK(x) ((x) < 0 ? (x) - 0.000001 : (x) + 0.000001)
@@ -832,7 +829,6 @@
// Keep a count of cases where the inter and intra were very close
// and very low. This helps with scene cut detection for example in
// cropped clips with black bars at the sides or top and bottom.
-#if INTRA_WEIGHT_EXPERIMENT
if (((this_error - intrapenalty) * 9 <= motion_error * 10) &&
(this_error < (2 * intrapenalty))) {neutral_count += 1.0;
@@ -843,12 +839,6 @@
neutral_count += (double)motion_error /
DOUBLE_DIVIDE_CHECK((double)this_error);
}
-#else
- if (((this_error - intrapenalty) * 9 <= motion_error * 10) &&
- (this_error < (2 * intrapenalty))) {- neutral_count += 1.0;
- }
-#endif
mv.row *= 8;
mv.col *= 8;
@@ -1291,11 +1281,10 @@
frame->pcnt_motion * ((frame->mvc_abs + frame->mvr_abs) / 2);
modified_pct_inter = frame->pcnt_inter;
-#if INTRA_WEIGHT_EXPERIMENT
if ((frame->intra_error / DOUBLE_DIVIDE_CHECK(frame->coded_error)) <
- (double)NCOUNT_FRAME_II_THRESH)
+ (double)NCOUNT_FRAME_II_THRESH) {modified_pct_inter = frame->pcnt_inter - frame->pcnt_neutral;
-#endif
+ }
modified_pcnt_intra = 100 * (1.0 - modified_pct_inter);
--- a/vp9/encoder/vp9_rdopt.c
+++ b/vp9/encoder/vp9_rdopt.c
@@ -50,7 +50,6 @@
#define MIN_EARLY_TERM_INDEX 3
#define NEW_MV_DISCOUNT_FACTOR 8
-#define SOURCE_VARIANCE_RD_ADJUSTMENT 0
typedef struct {PREDICTION_MODE mode;
@@ -2825,21 +2824,22 @@
rd_cost->rdcost = RDCOST(x->rdmult, x->rddiv, rd_cost->rate, rd_cost->dist);
}
-#if SOURCE_VARIANCE_RD_ADJUSTMENT
// This function is designed to apply a bias or adjustment to an rd value based
// on the relative variance of the source and reconstruction.
#define LOW_VAR_THRESH 16
-#define LOW_VAR_DIFF_THRESH 1
#define VLOW_ADJ_MAX 25
-#define VHIGH_ADJ_MAX 10
+#define VHIGH_ADJ_MAX 8
static void rd_variance_adjustment(VP9_COMP *cpi,
MACROBLOCK *x,
BLOCK_SIZE bsize,
int64_t *this_rd,
+ MV_REFERENCE_FRAME ref_frame,
unsigned int source_variance) {MACROBLOCKD *const xd = &x->e_mbd;
unsigned int recon_variance;
- unsigned int var_diff;
+ unsigned int absvar_diff = 0;
+ int64_t var_error = 0;
+ int64_t var_factor = 0;
if (*this_rd == INT64_MAX)
return;
@@ -2857,22 +2857,31 @@
vp9_get_sby_perpixel_variance(cpi, &xd->plane[0].dst, bsize);
#endif // CONFIG_VP9_HIGHBITDEPTH
- var_diff = (source_variance > recon_variance)
- ? (source_variance - recon_variance) : (recon_variance - source_variance);
+ if ((source_variance + recon_variance) > LOW_VAR_THRESH) {+ absvar_diff = (source_variance > recon_variance)
+ ? (source_variance - recon_variance)
+ : (recon_variance - source_variance);
- if ((source_variance > LOW_VAR_THRESH) && (var_diff > LOW_VAR_DIFF_THRESH)) {- unsigned int var_factor;
- if (source_variance > recon_variance) {- var_factor =
- MIN(VLOW_ADJ_MAX, (var_diff * VLOW_ADJ_MAX) / source_variance);
- } else {- var_factor =
- MIN(VHIGH_ADJ_MAX, (var_diff * VHIGH_ADJ_MAX) / source_variance);
- }
- *this_rd += (*this_rd * var_factor) / 100;
+ var_error = (200 * source_variance * recon_variance) /
+ ((source_variance * source_variance) +
+ (recon_variance * recon_variance));
+ var_error = 100 - var_error;
}
+
+ // Source variance above a threshold and ref frame is intra.
+ // This case is targeted mainly at discouraging intra modes that give rise
+ // to a predictor with a low spatial complexity compared to the source.
+ if ((source_variance > LOW_VAR_THRESH) && (ref_frame == INTRA_FRAME) &&
+ (source_variance > recon_variance)) {+ var_factor = MIN(absvar_diff, MIN(VLOW_ADJ_MAX, var_error));
+ // A second possible case of interest is where the source variance
+ // is very low and we wish to discourage false texture or motion trails.
+ } else if ((source_variance < (LOW_VAR_THRESH >> 1)) &&
+ (recon_variance > source_variance)) {+ var_factor = MIN(absvar_diff, MIN(VHIGH_ADJ_MAX, var_error));
+ }
+ *this_rd += (*this_rd * var_factor) / 100;
}
-#endif
void vp9_rd_pick_inter_mode_sb(VP9_COMP *cpi,
TileDataEnc *tile_data,
@@ -3330,11 +3339,10 @@
this_rd = RDCOST(x->rdmult, x->rddiv, rate2, distortion2);
}
-#if SOURCE_VARIANCE_RD_ADJUSTMENT
// Apply an adjustment to the rd value based on the similarity of the
// source variance and reconstructed variance.
- rd_variance_adjustment(cpi, x, bsize, &this_rd, x->source_variance);
-#endif
+ rd_variance_adjustment(cpi, x, bsize, &this_rd,
+ ref_frame, x->source_variance);
if (ref_frame == INTRA_FRAME) {// Keep record of best intra rd
--
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