ref: 4e8e7975e13feb96d3a5d9ed543c6a7ffb0335df
parent: e858863dda2e242ede57916dae4086a991f618dd
parent: 31228b3595d17e8323aede7bb364bd731c192820
author: Paul Wilkins <paulwilkins@google.com>
date: Mon Jul 23 09:50:13 EDT 2018
Merge "Improved coding on slide show content."
--- a/vp9/encoder/vp9_firstpass.c
+++ b/vp9/encoder/vp9_firstpass.c
@@ -2397,7 +2397,8 @@
// Define middle frame
mid_frame_idx = frame_index + (rc->baseline_gf_interval >> 1) - 1;
- normal_frames = (rc->baseline_gf_interval - rc->source_alt_ref_pending);
+ normal_frames =
+ rc->baseline_gf_interval - (key_frame || rc->source_alt_ref_pending);
for (i = 0; i < normal_frames; ++i) {int arf_idx = 0;
if (twopass->stats_in >= twopass->stats_in_end) break;
@@ -2859,8 +2860,9 @@
loop_decay_rate = get_prediction_decay_rate(cpi, &next_frame);
// Monitor for static sections.
- zero_motion_accumulator = VPXMIN(
- zero_motion_accumulator, get_zero_motion_factor(cpi, &next_frame));
+ if ((rc->frames_since_key + i - 1) > 1) {+ zero_motion_accumulator *= get_zero_motion_factor(cpi, &next_frame);
+ }
// Break clause to detect very still sections after motion. For example,
// a static image after a fade or other transition.
@@ -2881,9 +2883,18 @@
}
// Break out conditions.
- if (
- // Break at active_max_gf_interval unless almost totally static.
- ((i >= active_max_gf_interval) && (zero_motion_accumulator < 0.995)) ||
+ // Break at maximum of active_max_gf_interval unless almost totally static.
+ //
+ // Note that the addition of a test of rc->source_alt_ref_active is
+ // deliberate. The effect of this is that after a normal altref group even
+ // if the material is static there will be one normal length GF group
+ // before allowing longer GF groups. The reason for this is that in cases
+ // such as slide shows where slides are separated by a complex transition
+ // such as a fade, the arf group spanning the transition may not be coded
+ // at a very high quality and hence this frame (with its overlay) is a
+ // poor golden frame to use for an extended group.
+ if (((i >= active_max_gf_interval) &&
+ ((zero_motion_accumulator < 0.995) || (rc->source_alt_ref_active))) ||
(
// Don't break out with a very short interval.
(i >= active_min_gf_interval) &&
@@ -2903,8 +2914,8 @@
rc->constrained_gf_group = (i >= rc->frames_to_key) ? 1 : 0;
// Should we use the alternate reference frame.
- if (allow_alt_ref && (i < cpi->oxcf.lag_in_frames) &&
- (i >= rc->min_gf_interval)) {+ if ((zero_motion_accumulator < 0.995) && allow_alt_ref &&
+ (i < cpi->oxcf.lag_in_frames) && (i >= rc->min_gf_interval)) {const int forward_frames = (rc->frames_to_key - i >= i - 1)
? i - 1
: VPXMAX(0, rc->frames_to_key - i);
@@ -2931,8 +2942,11 @@
rc->gfu_boost = VPXMIN((int)rc->gfu_boost, i * 200);
#endif
- // Set the interval until the next gf.
- rc->baseline_gf_interval = i - (is_key_frame || rc->source_alt_ref_pending);
+ rc->baseline_gf_interval =
+ ((twopass->kf_zeromotion_pct >= STATIC_KF_GROUP_THRESH) &&
+ (i >= rc->frames_to_key))
+ ? i
+ : (i - (is_key_frame || rc->source_alt_ref_pending));
rc->frames_till_gf_update_due = rc->baseline_gf_interval;
@@ -3216,6 +3230,7 @@
vp9_zero(next_frame);
cpi->common.frame_type = KEY_FRAME;
+ rc->frames_since_key = 0;
// Reset the GF group data structures.
vp9_zero(*gf_group);
@@ -3360,13 +3375,22 @@
for (i = 0; i < (rc->frames_to_key - 1); ++i) {if (EOF == input_stats(twopass, &next_frame)) break;
- if (i <= KF_BOOST_SCAN_MAX_FRAMES) {+ // The zero motion test here insures that if we mark a kf group as static
+ // it is static throughout not just the first KF_BOOST_SCAN_MAX_FRAMES.
+ // It also allows for a larger boost on long static groups.
+ if ((i <= KF_BOOST_SCAN_MAX_FRAMES) || (zero_motion_accumulator >= 0.99)) {double frame_boost;
double zm_factor;
// Monitor for static sections.
- zero_motion_accumulator = VPXMIN(
- zero_motion_accumulator, get_zero_motion_factor(cpi, &next_frame));
+ // First frame in kf group the second ref indicator is invalid.
+ if (i > 0) {+ zero_motion_accumulator = VPXMIN(
+ zero_motion_accumulator, get_zero_motion_factor(cpi, &next_frame));
+ } else {+ zero_motion_accumulator =
+ next_frame.pcnt_inter - next_frame.pcnt_motion;
+ }
// Factor 0.75-1.25 based on how much of frame is static.
zm_factor = (0.75 + (zero_motion_accumulator / 2.0));
@@ -3403,10 +3427,16 @@
twopass->section_intra_rating = calculate_section_intra_ratio(
start_position, twopass->stats_in_end, rc->frames_to_key);
- // Apply various clamps for min and max boost
- rc->kf_boost = VPXMAX((int)boost_score, (rc->frames_to_key * 3));
- rc->kf_boost = VPXMAX(rc->kf_boost, MIN_KF_TOT_BOOST);
- rc->kf_boost = VPXMIN(rc->kf_boost, MAX_KF_TOT_BOOST);
+ // Special case for static / slide show content but dont apply
+ // if the kf group is very short.
+ if ((zero_motion_accumulator > 0.99) && (rc->frames_to_key > 8)) {+ rc->kf_boost = VPXMAX((rc->frames_to_key * 100), MAX_KF_TOT_BOOST);
+ } else {+ // Apply various clamps for min and max boost
+ rc->kf_boost = VPXMAX((int)boost_score, (rc->frames_to_key * 3));
+ rc->kf_boost = VPXMAX(rc->kf_boost, MIN_KF_TOT_BOOST);
+ rc->kf_boost = VPXMIN(rc->kf_boost, MAX_KF_TOT_BOOST);
+ }
// Work out how many bits to allocate for the key frame itself.
kf_bits = calculate_boost_bits((rc->frames_to_key - 1), rc->kf_boost,
--- a/vp9/encoder/vp9_firstpass.h
+++ b/vp9/encoder/vp9_firstpass.h
@@ -134,14 +134,14 @@
typedef struct {unsigned char index;
unsigned char first_inter_index;
- RATE_FACTOR_LEVEL rf_level[(MAX_LAG_BUFFERS * 2) + 1];
- FRAME_UPDATE_TYPE update_type[(MAX_LAG_BUFFERS * 2) + 1];
- unsigned char arf_src_offset[(MAX_LAG_BUFFERS * 2) + 1];
- unsigned char arf_update_idx[(MAX_LAG_BUFFERS * 2) + 1];
- unsigned char arf_ref_idx[(MAX_LAG_BUFFERS * 2) + 1];
- unsigned char brf_src_offset[(MAX_LAG_BUFFERS * 2) + 1];
- unsigned char bidir_pred_enabled[(MAX_LAG_BUFFERS * 2) + 1];
- int bit_allocation[(MAX_LAG_BUFFERS * 2) + 1];
+ RATE_FACTOR_LEVEL rf_level[MAX_STATIC_GF_GROUP_LENGTH + 2];
+ FRAME_UPDATE_TYPE update_type[MAX_STATIC_GF_GROUP_LENGTH + 2];
+ unsigned char arf_src_offset[MAX_STATIC_GF_GROUP_LENGTH + 2];
+ unsigned char arf_update_idx[MAX_STATIC_GF_GROUP_LENGTH + 2];
+ unsigned char arf_ref_idx[MAX_STATIC_GF_GROUP_LENGTH + 2];
+ unsigned char brf_src_offset[MAX_STATIC_GF_GROUP_LENGTH + 2];
+ unsigned char bidir_pred_enabled[MAX_STATIC_GF_GROUP_LENGTH + 2];
+ int bit_allocation[MAX_STATIC_GF_GROUP_LENGTH + 2];
} GF_GROUP;
typedef struct {--- a/vp9/encoder/vp9_ratectrl.c
+++ b/vp9/encoder/vp9_ratectrl.c
@@ -1242,7 +1242,15 @@
// Baseline value derived from cpi->active_worst_quality and kf boost.
active_best_quality =
get_kf_active_quality(rc, active_worst_quality, cm->bit_depth);
+ if (cpi->twopass.kf_zeromotion_pct >= STATIC_KF_GROUP_THRESH) {+ active_best_quality /= 4;
+ }
+ // Dont allow the active min to be lossless (q0) unlesss the max q
+ // already indicates lossless.
+ active_best_quality =
+ VPXMIN(active_worst_quality, VPXMAX(1, active_best_quality));
+
// Allow somewhat lower kf minq with small image formats.
if ((cm->width * cm->height) <= (352 * 288)) {q_adj_factor -= 0.25;
@@ -2184,13 +2192,8 @@
rc->max_gf_interval = vp9_rc_get_default_max_gf_interval(
cpi->framerate, rc->min_gf_interval);
- // Extended interval for genuinely static scenes
- rc->static_scene_max_gf_interval = MAX_LAG_BUFFERS * 2;
-
- if (is_altref_enabled(cpi)) {- if (rc->static_scene_max_gf_interval > oxcf->lag_in_frames - 1)
- rc->static_scene_max_gf_interval = oxcf->lag_in_frames - 1;
- }
+ // Extended max interval for genuinely static scenes like slide shows.
+ rc->static_scene_max_gf_interval = MAX_STATIC_GF_GROUP_LENGTH;
if (rc->max_gf_interval > rc->static_scene_max_gf_interval)
rc->max_gf_interval = rc->static_scene_max_gf_interval;
--- a/vp9/encoder/vp9_ratectrl.h
+++ b/vp9/encoder/vp9_ratectrl.h
@@ -34,6 +34,14 @@
#define FRAME_OVERHEAD_BITS 200
+// Threshold used to define a KF group as static (e.g. a slide show).
+// Essentially this means that no frame in the group has more than 1% of MBs
+// that are not marked as coded with 0,0 motion in the first pass.
+#define STATIC_KF_GROUP_THRESH 99
+
+// The maximum duration of a GF group that is static (for example a slide show).
+#define MAX_STATIC_GF_GROUP_LENGTH 250
+
typedef enum {INTER_NORMAL = 0,
INTER_HIGH = 1,