From: Paul Wilkins <paulwilkins@google.com>
Date: Wed, 11 Dec 2013 15:03:04 +0000 (+0000)
Subject: Allow arf just before kfs or end of sequence.
X-Git-Tag: v1.4.0~2789
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=cb8659981d0ca11e259946dd97269ad0a8ee0cb4;p=libvpx

Allow arf just before kfs or end of sequence.

This will hurt metrics in some cases (particularly for static
clips at low data rates where there is extra overhead, but it
helps smooth transitions around forced key frames between
stitched kf sections.

Change-Id: I7e1026ae0de6c77bba863061e115136d7f283cc0
---

diff --git a/vp9/encoder/vp9_firstpass.c b/vp9/encoder/vp9_firstpass.c
index d2bcabe27..2d7ac7ce5 100644
--- a/vp9/encoder/vp9_firstpass.c
+++ b/vp9/encoder/vp9_firstpass.c
@@ -1639,9 +1639,8 @@ static void define_gf_group(VP9_COMP *cpi, FIRSTPASS_STATS *this_frame) {
     active_max_gf_interval = cpi->rc.max_gf_interval;
 
   i = 0;
-  while (((i < cpi->twopass.static_scene_max_gf_interval) ||
-          ((cpi->rc.frames_to_key - i) < MIN_GF_INTERVAL)) &&
-         (i < cpi->rc.frames_to_key)) {
+  while ((i < cpi->twopass.static_scene_max_gf_interval) &&
+         (i < (cpi->rc.frames_to_key - 1))) {
     i++;    // Increment the loop counter
 
     // Accumulate error score of frames in this gf group
@@ -1695,8 +1694,6 @@ static void define_gf_group(VP9_COMP *cpi, FIRSTPASS_STATS *this_frame) {
       (
         // Don't break out with a very short interval
         (i > MIN_GF_INTERVAL) &&
-        // Don't break out very close to a key frame
-        ((cpi->rc.frames_to_key - i) >= MIN_GF_INTERVAL) &&
         ((boost_score > 125.0) || (next_frame.pcnt_inter < 0.75)) &&
         (!flash_detected) &&
         ((mv_ratio_accumulator > mv_ratio_accumulator_thresh) ||
@@ -1716,7 +1713,7 @@ static void define_gf_group(VP9_COMP *cpi, FIRSTPASS_STATS *this_frame) {
 
   // Don't allow a gf too near the next kf
   if ((cpi->rc.frames_to_key - i) < MIN_GF_INTERVAL) {
-    while (i < cpi->rc.frames_to_key) {
+    while (i < (cpi->rc.frames_to_key - 1)) {
       i++;
 
       if (EOF == input_stats(cpi, this_frame))
@@ -1729,6 +1726,7 @@ static void define_gf_group(VP9_COMP *cpi, FIRSTPASS_STATS *this_frame) {
     }
   }
 
+
   // Set the interval until the next gf or arf.
   cpi->rc.baseline_gf_interval = i;
 
@@ -1748,8 +1746,6 @@ static void define_gf_group(VP9_COMP *cpi, FIRSTPASS_STATS *this_frame) {
   if (allow_alt_ref &&
       (i < cpi->oxcf.lag_in_frames) &&
       (i >= MIN_GF_INTERVAL) &&
-      // dont use ARF very near next kf
-      (i <= (cpi->rc.frames_to_key - MIN_GF_INTERVAL)) &&
       ((next_frame.pcnt_inter > 0.75) ||
        (next_frame.pcnt_second_ref > 0.5)) &&
       ((mv_in_out_accumulator / (double)i > -0.2) ||