Further CQ, Key frame and ARF changes

This code fixes a bug in the calculation of
the minimum Q for alt ref frames.

It also allows an extended gf/arf interval for sections
of clips that completely static (or nearly so).

Change-Id: I1a21aaa16d4f0578e5f99b13bebd78d59403c73b

diff --git a/vp8/encoder/encodeframe.c b/vp8/encoder/encodeframe.c
index 2a89c59f44f8e9ce41f1041343113e356a3ead2d..4c95f28d64ca54504eab688a836d51bbe856fc1d 100644 (file)
--- a/vp8/encoder/encodeframe.c
+++ b/vp8/encoder/encodeframe.c
@@ -710,9 +710,7 @@ void vp8_encode_frame(VP8_COMP *cpi)
     }
 
     vp8_initialize_rd_consts(cpi, vp8_dc_quant(cm->base_qindex, cm->y1dc_delta_q));
-    //vp8_initialize_rd_consts( cpi, vp8_dc_quant(cpi->avg_frame_qindex, cm->y1dc_delta_q) );
     vp8cx_initialize_me_consts(cpi, cm->base_qindex);
-    //vp8cx_initialize_me_consts( cpi, cpi->avg_frame_qindex);
 
     // Copy data over into macro block data sturctures.
 

diff --git a/vp8/encoder/firstpass.c b/vp8/encoder/firstpass.c
index c596138380e525aebc430562f1604f9982bfaccb..32a39c5f27852e6190f89cbe53dd8dafa0b53a70 100644 (file)
--- a/vp8/encoder/firstpass.c
+++ b/vp8/encoder/firstpass.c
@@ -1375,7 +1375,7 @@ static void define_gf_group(VP8_COMP *cpi, FIRSTPASS_STATS *this_frame)
     // what level of boost is appropriate for the GF or ARF that will be coded with the group
     i = 0;
 
-    while (((i < cpi->max_gf_interval) || ((cpi->frames_to_key - i) < MIN_GF_INTERVAL)) && (i < cpi->frames_to_key))
+    while (((i < cpi->static_scene_max_gf_interval) || ((cpi->frames_to_key - i) < MIN_GF_INTERVAL)) && (i < cpi->frames_to_key))
     {
         double r;
         double this_frame_mvr_ratio;
@@ -1485,18 +1485,20 @@ static void define_gf_group(VP8_COMP *cpi, FIRSTPASS_STATS *this_frame)
         boost_score += (decay_accumulator * r);
 
         // Break out conditions.
-        if (   /* i>4 || */
+        if  (   /* i>4 || */
+            // Break at cpi->max_gf_interval unless almost totally static
+            (i >= cpi->max_gf_interval && (loop_decay_rate < 0.99)) ||
             (
-                (i > MIN_GF_INTERVAL) &&                            // Dont break out with a very short interval
-                ((cpi->frames_to_key - i) >= MIN_GF_INTERVAL) &&      // Dont break out very close to a key frame
+                // Dont break out with a very short interval
+                (i > MIN_GF_INTERVAL) &&
+                // Dont break out very close to a key frame
+                ((cpi->frames_to_key - i) >= MIN_GF_INTERVAL) &&
                 ((boost_score > 20.0) || (next_frame.pcnt_inter < 0.75)) &&
                 ((mv_ratio_accumulator > 100.0) ||
                  (abs_mv_in_out_accumulator > 3.0) ||
                  (mv_in_out_accumulator < -2.0) ||
-                 ((boost_score - old_boost_score) < 2.0)
-                )
-            )
-        )
+                 ((boost_score - old_boost_score) < 2.0))
+            ) )
         {
             boost_score = old_boost_score;
             break;

diff --git a/vp8/encoder/onyx_if.c b/vp8/encoder/onyx_if.c
index 47fc3f78e02377b9c87a1be10f18954507c72614..846ebb4bb8f795f3f06d3f79ad71b82005f25b93 100644 (file)
--- a/vp8/encoder/onyx_if.c
+++ b/vp8/encoder/onyx_if.c
@@ -1497,21 +1497,25 @@ void vp8_new_frame_rate(VP8_COMP *cpi, double framerate)
     cpi->per_frame_bandwidth          = (int)(cpi->oxcf.target_bandwidth / cpi->output_frame_rate);
     cpi->av_per_frame_bandwidth        = (int)(cpi->oxcf.target_bandwidth / cpi->output_frame_rate);
     cpi->min_frame_bandwidth          = (int)(cpi->av_per_frame_bandwidth * cpi->oxcf.two_pass_vbrmin_section / 100);
-    cpi->max_gf_interval = (int)(cpi->output_frame_rate / 2) + 2;
 
-    //cpi->max_gf_interval = (int)(cpi->output_frame_rate * 2 / 3) + 1;
-    //cpi->max_gf_interval = 24;
+    // Set Maximum gf/arf interval
+    cpi->max_gf_interval = max(((int)(cpi->output_frame_rate / 2.0) + 2), 12);
 
-    if (cpi->max_gf_interval < 12)
-        cpi->max_gf_interval = 12;
+    // Extended interval for genuinely static scenes
+    cpi->static_scene_max_gf_interval = cpi->key_frame_frequency >> 1;
 
-
-    // Special conditions when altr ref frame enabled in lagged compress mode
+     // Special conditions when altr ref frame enabled in lagged compress mode
     if (cpi->oxcf.play_alternate && cpi->oxcf.lag_in_frames)
     {
         if (cpi->max_gf_interval > cpi->oxcf.lag_in_frames - 1)
             cpi->max_gf_interval = cpi->oxcf.lag_in_frames - 1;
+
+        if (cpi->static_scene_max_gf_interval > cpi->oxcf.lag_in_frames - 1)
+            cpi->static_scene_max_gf_interval = cpi->oxcf.lag_in_frames - 1;
     }
+
+    if ( cpi->max_gf_interval > cpi->static_scene_max_gf_interval )
+        cpi->max_gf_interval = cpi->static_scene_max_gf_interval;
 }
 
 
@@ -3846,9 +3850,21 @@ static void encode_frame_to_data_rate
 
         else if (cm->refresh_golden_frame || cpi->common.refresh_alt_ref_frame)
         {
-            if (cpi->avg_frame_qindex < cpi->active_worst_quality)
+            // Use the lower of cpi->active_worst_quality and recent
+            // average Q as basis for GF/ARF Q limit unless last frame was
+            // a key frame.
+            if ( (cpi->frames_since_key > 1) &&
+                 (cpi->avg_frame_qindex < cpi->active_worst_quality) )
+            {
                 Q = cpi->avg_frame_qindex;
 
+                if ( (cpi->oxcf.end_usage == USAGE_CONSTRAINED_QUALITY) &&
+                     (Q < cpi->oxcf.cq_level) )
+                {
+                    Q = cpi->oxcf.cq_level;
+                }
+            }
+
             if ( cpi->pass == 2 )
             {
                 if ( cpi->gfu_boost > 1000 )
@@ -4528,9 +4544,7 @@ static void encode_frame_to_data_rate
     }
 
     // Keep a record of ambient average Q.
-    if (cm->frame_type == KEY_FRAME)
-        cpi->avg_frame_qindex = cm->base_qindex;
-    else
+    if (cm->frame_type != KEY_FRAME)
         cpi->avg_frame_qindex = (2 + 3 * cpi->avg_frame_qindex + cm->base_qindex) >> 2;
 
     // Keep a record from which we can calculate the average Q excluding GF updates and key frames

diff --git a/vp8/encoder/onyx_int.h b/vp8/encoder/onyx_int.h
index 45fafd5b65559186be95cff7a34a607f267aeba3..8a97e983b388e835759a70c8d53e4f8ea2cda282 100644 (file)
--- a/vp8/encoder/onyx_int.h
+++ b/vp8/encoder/onyx_int.h
@@ -402,6 +402,7 @@ typedef struct
     int kf_overspend_bits;            // Extra bits spent on key frames that need to be recovered on inter frames
     int kf_bitrate_adjustment;        // Current number of bit s to try and recover on each inter frame.
     int max_gf_interval;
+    int static_scene_max_gf_interval;
     int baseline_gf_interval;
     int gf_decay_rate;
     int active_arnr_frames;           // <= cpi->oxcf.arnr_max_frames