Enable various thresholds of motion detection

This commit changed to enable the encoder to adjust motion dection
speed threshold based on picture size. In addition, cpu-used 1 now
does a partition search every other frame instead of every third
frame for low resolution inputs.

The change has no quality/speed impact for 720p and above. Test
showed the change increase encoding time by between 3% to 6% for
cpu-used 2 encodiong of 360p sequences. It also has a compression
gain about .3%.

For cpu-used 2, the change resolved some very disturbing visual
artifacts in certain sequences when large block partitionings and
transforms are used as a result of copying the partition from a
previous frame.

Change-Id: Ic7fd22508cdb811d4ca935655adbf20109286cfa

3 files changed, 25 insertions, 9 deletions

diff --git a/vp9/encoder/vp9_encodeframe.c b/vp9/encoder/vp9_encodeframe.c
index f7cb05b78..73e32ce68 100644
--- a/vp9/encoder/vp9_encodeframe.c
+++ b/vp9/encoder/vp9_encodeframe.c
@@ -1312,7 +1312,8 @@ static int is_background(VP9_COMP *cpi, const TileInfo *const tile,
   return x->in_static_area;
 }
 
-static int sb_has_motion(const VP9_COMMON *cm, MODE_INFO **prev_mi_8x8) {
+static int sb_has_motion(const VP9_COMMON *cm, MODE_INFO **prev_mi_8x8,
+                         const int motion_thresh) {
   const int mis = cm->mi_stride;
   int block_row, block_col;
 
@@ -1321,8 +1322,8 @@ static int sb_has_motion(const VP9_COMMON *cm, MODE_INFO **prev_mi_8x8) {
       for (block_col = 0; block_col < 8; ++block_col) {
         const MODE_INFO *prev_mi = prev_mi_8x8[block_row * mis + block_col];
         if (prev_mi) {
-          if (abs(prev_mi->mbmi.mv[0].as_mv.row) >= 8 ||
-              abs(prev_mi->mbmi.mv[0].as_mv.col) >= 8)
+          if (abs(prev_mi->mbmi.mv[0].as_mv.row) > motion_thresh ||
+              abs(prev_mi->mbmi.mv[0].as_mv.col) > motion_thresh)
             return 1;
         }
       }
@@ -2318,7 +2319,7 @@ static void encode_rd_sb_row(VP9_COMP *cpi, const TileInfo *const tile,
             || cpi->rc.is_src_frame_alt_ref
             || ((sf->use_lastframe_partitioning ==
                  LAST_FRAME_PARTITION_LOW_MOTION) &&
-                 sb_has_motion(cm, prev_mi))) {
+                 sb_has_motion(cm, prev_mi, sf->lf_motion_threshold))) {
           // If required set upper and lower partition size limits
           if (sf->auto_min_max_partition_size) {
             set_offsets(cpi, tile, mi_row, mi_col, BLOCK_64X64);
@@ -2331,7 +2332,7 @@ static void encode_rd_sb_row(VP9_COMP *cpi, const TileInfo *const tile,
                             cpi->pc_root);
         } else {
           if (sf->constrain_copy_partition &&
-              sb_has_motion(cm, prev_mi))
+              sb_has_motion(cm, prev_mi, sf->lf_motion_threshold))
             constrain_copy_partitioning(cpi, tile, mi, prev_mi,
                                         mi_row, mi_col, BLOCK_16X16);
           else
diff --git a/vp9/encoder/vp9_speed_features.c b/vp9/encoder/vp9_speed_features.c
index 93e23eee2..4ba5a59a3 100644
--- a/vp9/encoder/vp9_speed_features.c
+++ b/vp9/encoder/vp9_speed_features.c
@@ -80,12 +80,16 @@ static void set_good_speed_feature(VP9_COMP *cpi, VP9_COMMON *cm,
   }
 
   if (speed >= 2) {
-    if (MIN(cm->width, cm->height) >= 720)
+    if (MIN(cm->width, cm->height) >= 720) {
+      sf->lf_motion_threshold = LOW_MOITION_THRESHOLD;
+      sf->last_partitioning_redo_frequency = 3;
       sf->disable_split_mask = cm->show_frame ? DISABLE_ALL_SPLIT
                                               : DISABLE_ALL_INTER_SPLIT;
-    else
+    } else {
       sf->disable_split_mask = LAST_AND_INTRA_SPLIT_ONLY;
-
+      sf->last_partitioning_redo_frequency = 2;
+      sf->lf_motion_threshold = NO_MOITION_THRESHOLD;
+    }
     sf->adaptive_pred_interp_filter = 2;
     sf->reference_masking = 1;
     sf->mode_search_skip_flags = FLAG_SKIP_INTRA_DIRMISMATCH |
@@ -97,7 +101,6 @@ static void set_good_speed_feature(VP9_COMP *cpi, VP9_COMMON *cm,
     sf->auto_min_max_partition_size = RELAXED_NEIGHBORING_MIN_MAX;
     sf->use_lastframe_partitioning = LAST_FRAME_PARTITION_LOW_MOTION;
     sf->adjust_partitioning_from_last_frame = 1;
-    sf->last_partitioning_redo_frequency = 3;
   }
 
   if (speed >= 3) {
@@ -108,6 +111,8 @@ static void set_good_speed_feature(VP9_COMP *cpi, VP9_COMMON *cm,
     else
       sf->disable_split_mask = DISABLE_ALL_INTER_SPLIT;
 
+    sf->lf_motion_threshold = LOW_MOITION_THRESHOLD;
+    sf->last_partitioning_redo_frequency = 3;
     sf->recode_loop = ALLOW_RECODE_KFMAXBW;
     sf->adaptive_rd_thresh = 3;
     sf->mode_skip_start = 6;
@@ -198,6 +203,7 @@ static void set_rt_speed_feature(VP9_COMMON *cm, SPEED_FEATURES *sf,
 
     sf->auto_min_max_partition_size = RELAXED_NEIGHBORING_MIN_MAX;
     sf->use_lastframe_partitioning = LAST_FRAME_PARTITION_LOW_MOTION;
+    sf->lf_motion_threshold = LOW_MOITION_THRESHOLD;
     sf->adjust_partitioning_from_last_frame = 1;
     sf->last_partitioning_redo_frequency = 3;
 
diff --git a/vp9/encoder/vp9_speed_features.h b/vp9/encoder/vp9_speed_features.h
index 46806c9a9..6d2cbb9a9 100644
--- a/vp9/encoder/vp9_speed_features.h
+++ b/vp9/encoder/vp9_speed_features.h
@@ -44,6 +44,11 @@ typedef enum {
 } SUBPEL_SEARCH_METHODS;
 
 typedef enum {
+  NO_MOITION_THRESHOLD = 0,
+  LOW_MOITION_THRESHOLD = 7
+} MOTION_THRESHOLD;
+
+typedef enum {
   LAST_FRAME_PARTITION_OFF = 0,
   LAST_FRAME_PARTITION_LOW_MOTION = 1,
   LAST_FRAME_PARTITION_ALL = 2
@@ -200,6 +205,10 @@ typedef struct SPEED_FEATURES {
   // partitioning.
   LAST_FRAME_PARTITION_METHOD use_lastframe_partitioning;
 
+  // The threshold is to determine how slow the motino is, it is used when
+  // use_lastframe_partitioning is set to LAST_FRAME_PARTITION_LOW_MOTION
+  MOTION_THRESHOLD lf_motion_threshold;
+
   // Determine which method we use to determine transform size. We can choose
   // between options like full rd, largest for prediction size, largest
   // for intra and model coefs for the rest.