ref: b29c48b03c4bff441b0d43ab8c5eab214fd0ab1b
parent: b12f531cc52945aaa51d51bf98b9237caf8b8fe3
author: paulwilkins <[email protected]>
date: Fri Mar 6 11:32:20 EST 2015
Shorten GF/arf interval in hard scenes. This patch accounts in the first pass stats for blocks that while not coded as intra, are complex and have an intra error / best error ratio below a threshold. The modification shortens the GF arf interval for a particular class of content that contains a lot of blocks matching the above criteria. (In one short problem test sequence the average interval dropped from about 14-15 to 10-11) The change results in small net gains in metrics results for the Yt(~0.2%) and yt-hd (~0.5%) sets and is approximately neutral for the other test sets. The change is currently shielded by a flag and off by default pending verification that it does not cause other regressions in tests on a wider YT test set. Change-Id: I6b803daa6a4ac09a6f428fb3a18be1ecedd974b7
--- a/vp9/encoder/vp9_firstpass.c
+++ b/vp9/encoder/vp9_firstpass.c
@@ -60,6 +60,14 @@
#define RC_FACTOR_MIN 0.75
#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)
#if ARF_STATS_OUTPUT
@@ -470,7 +478,7 @@
int intercount = 0;
int second_ref_count = 0;
const int intrapenalty = INTRA_MODE_PENALTY;
- int neutral_count = 0;
+ double neutral_count;
int new_mv_count = 0;
int sum_in_vectors = 0;
MV lastmv = {0, 0};@@ -503,6 +511,7 @@
intra_factor = 0.0;
brightness_factor = 0.0;
+ neutral_count = 0.0;
set_first_pass_params(cpi);
vp9_set_quantizer(cm, find_fp_qindex(cm->bit_depth));
@@ -818,12 +827,28 @@
#endif
if (motion_error <= this_error) {+ vp9_clear_system_state();
+
// 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;
+ (this_error < (2 * intrapenalty))) {+ neutral_count += 1.0;
+ // Also track cases where the intra is not much worse than the inter
+ // and use this in limiting the GF/arf group length.
+ } else if ((this_error > NCOUNT_INTRA_THRESH) &&
+ (this_error < (NCOUNT_INTRA_FACTOR * motion_error))) {+ 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;
@@ -1260,17 +1285,27 @@
double sr_diff =
(frame->sr_coded_error - frame->coded_error) / num_mbs;
double sr_decay = 1.0;
+ double modified_pct_inter;
+ double modified_pcnt_intra;
const double motion_amplitude_factor =
frame->pcnt_motion * ((frame->mvc_abs + frame->mvr_abs) / 2);
- const double pcnt_intra = 100 * (1.0 - frame->pcnt_inter);
+ 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)
+ modified_pct_inter = frame->pcnt_inter - frame->pcnt_neutral;
+#endif
+ modified_pcnt_intra = 100 * (1.0 - modified_pct_inter);
+
+
if ((sr_diff > LOW_SR_DIFF_TRHESH)) {sr_diff = MIN(sr_diff, SR_DIFF_MAX);
sr_decay = 1.0 - (SR_DIFF_PART * sr_diff) -
(MOTION_AMP_PART * motion_amplitude_factor) -
- (INTRA_PART * pcnt_intra);
+ (INTRA_PART * modified_pcnt_intra);
}
- return MAX(sr_decay, MIN(DEFAULT_DECAY_LIMIT, frame->pcnt_inter));
+ return MAX(sr_decay, MIN(DEFAULT_DECAY_LIMIT, modified_pct_inter));
}
// This function gives an estimate of how badly we believe the prediction