shithub: libvpx

Download patch

ref: 7f7782bebdcb43708bda2f88e4ae21e4319bdf29
parent: eb012d74f89cdd40579803e90fa59c07e66a45c4
parent: 39fa0777e3445b04090f35ac396a33ad3a583351
author: James Zern <jzern@google.com>
date: Wed May 30 17:25:55 EDT 2018

Merge "Revert 3 slide show coding changes"

--- a/vp9/encoder/vp9_firstpass.c
+++ b/vp9/encoder/vp9_firstpass.c
@@ -2201,8 +2201,7 @@
   // Define middle frame
   mid_frame_idx = frame_index + (rc->baseline_gf_interval >> 1) - 1;
 
-  normal_frames =
-      rc->baseline_gf_interval - (key_frame || rc->source_alt_ref_pending);
+  normal_frames = (rc->baseline_gf_interval - rc->source_alt_ref_pending);
   if (normal_frames > 1)
     normal_frame_bits = (int)(total_group_bits / normal_frames);
   else
@@ -2441,9 +2440,8 @@
       loop_decay_rate = get_prediction_decay_rate(cpi, &next_frame);
 
       // Monitor for static sections.
-      if ((rc->frames_since_key + i - 1) > 1) {
-        zero_motion_accumulator *= get_zero_motion_factor(cpi, &next_frame);
-      }
+      zero_motion_accumulator = VPXMIN(
+          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.
@@ -2464,18 +2462,9 @@
     }
 
     // Break out conditions.
-    // 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))) ||
+    if (
+        // Break at active_max_gf_interval unless almost totally static.
+        ((i >= active_max_gf_interval) && (zero_motion_accumulator < 0.995)) ||
         (
             // Don't break out with a very short interval.
             (i >= active_min_gf_interval) &&
@@ -2495,8 +2484,8 @@
   rc->constrained_gf_group = (i >= rc->frames_to_key) ? 1 : 0;
 
   // Should we use the alternate reference frame.
-  if ((zero_motion_accumulator < 0.995) && allow_alt_ref &&
-      (i < cpi->oxcf.lag_in_frames) && (i >= rc->min_gf_interval)) {
+  if (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);
@@ -2523,11 +2512,8 @@
   rc->gfu_boost = VPXMIN((int)rc->gfu_boost, i * 200);
 #endif
 
-  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));
+  // Set the interval until the next gf.
+  rc->baseline_gf_interval = i - (is_key_frame || rc->source_alt_ref_pending);
 
   rc->frames_till_gf_update_due = rc->baseline_gf_interval;
 
@@ -2774,7 +2760,6 @@
   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);
@@ -2919,22 +2904,13 @@
   for (i = 0; i < (rc->frames_to_key - 1); ++i) {
     if (EOF == input_stats(twopass, &next_frame)) break;
 
-    // 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)) {
+    if (i <= KF_BOOST_SCAN_MAX_FRAMES) {
       double frame_boost;
       double zm_factor;
 
       // Monitor for static sections.
-      // 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;
-      }
+      zero_motion_accumulator = VPXMIN(
+          zero_motion_accumulator, get_zero_motion_factor(cpi, &next_frame));
 
       // Factor 0.75-1.25 based on how much of frame is static.
       zm_factor = (0.75 + (zero_motion_accumulator / 2.0));
@@ -2971,16 +2947,10 @@
   twopass->section_intra_rating = calculate_section_intra_ratio(
       start_position, twopass->stats_in_end, rc->frames_to_key);
 
-  // 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);
-  }
+  // 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
@@ -120,12 +120,12 @@
 typedef struct {
   unsigned char index;
   unsigned char first_inter_index;
-  RATE_FACTOR_LEVEL rf_level[MAX_STATIC_GF_GROUP_LENGTH + 1];
-  FRAME_UPDATE_TYPE update_type[MAX_STATIC_GF_GROUP_LENGTH + 1];
-  unsigned char arf_src_offset[MAX_STATIC_GF_GROUP_LENGTH + 1];
-  unsigned char arf_update_idx[MAX_STATIC_GF_GROUP_LENGTH + 1];
-  unsigned char arf_ref_idx[MAX_STATIC_GF_GROUP_LENGTH + 1];
-  int bit_allocation[MAX_STATIC_GF_GROUP_LENGTH + 1];
+  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];
+  int bit_allocation[(MAX_LAG_BUFFERS * 2) + 1];
 } GF_GROUP;
 
 typedef struct {
--- a/vp9/encoder/vp9_ratectrl.c
+++ b/vp9/encoder/vp9_ratectrl.c
@@ -1227,9 +1227,6 @@
       // 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;
-      }
 
       // Allow somewhat lower kf minq with small image formats.
       if ((cm->width * cm->height) <= (352 * 288)) {
@@ -1976,8 +1973,13 @@
       rc->max_gf_interval = vp9_rc_get_default_max_gf_interval(
           cpi->framerate, rc->min_gf_interval);
 
-    // Extended max interval for genuinely static scenes like slide shows.
-    rc->static_scene_max_gf_interval = MAX_STATIC_GF_GROUP_LENGTH;
+    // 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;
+    }
 
     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
@@ -34,14 +34,6 @@
 
 #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 25
-
 typedef enum {
   INTER_NORMAL = 0,
   INTER_HIGH = 1,