Revert "Force ARNR filtering to be centered on the ARF frame"

This reverts commit 59e733ca81b707780901340686ecd7419077eb54.

Hold off removing arnr_type to give users the opportunity
to change their script files to handle its deprecation. A
follow-up patch will mark the control for setting arnr_type
as deprecated and it will be removed completely in a later
revision of the code.

Change-Id: I8b817c744e144d3714234a4cd4309816d0c7e3e8

7 files changed, 109 insertions, 36 deletions

diff --git a/test/borders_test.cc b/test/borders_test.cc
index a2f5a1bdd..b30be4580 100644
--- a/test/borders_test.cc
+++ b/test/borders_test.cc
@@ -35,6 +35,7 @@ class BordersTest : public ::libvpx_test::EncoderTest,
       encoder->Control(VP8E_SET_ENABLEAUTOALTREF, 1);
       encoder->Control(VP8E_SET_ARNR_MAXFRAMES, 7);
       encoder->Control(VP8E_SET_ARNR_STRENGTH, 5);
+      encoder->Control(VP8E_SET_ARNR_TYPE, 3);
     }
   }
 
diff --git a/test/cpu_speed_test.cc b/test/cpu_speed_test.cc
index ca201bbc7..be651b4fe 100644
--- a/test/cpu_speed_test.cc
+++ b/test/cpu_speed_test.cc
@@ -37,6 +37,7 @@ class CpuSpeedTest : public ::libvpx_test::EncoderTest,
       encoder->Control(VP8E_SET_ENABLEAUTOALTREF, 1);
       encoder->Control(VP8E_SET_ARNR_MAXFRAMES, 7);
       encoder->Control(VP8E_SET_ARNR_STRENGTH, 5);
+      encoder->Control(VP8E_SET_ARNR_TYPE, 3);
     }
   }
 
diff --git a/vp9/encoder/vp9_encoder.h b/vp9/encoder/vp9_encoder.h
index 8f3249407..7483f7fd1 100644
--- a/vp9/encoder/vp9_encoder.h
+++ b/vp9/encoder/vp9_encoder.h
@@ -276,6 +276,7 @@ typedef struct VP9EncoderConfig {
 
   int arnr_max_frames;
   int arnr_strength;
+  int arnr_type;
 
   int tile_columns;
   int tile_rows;
diff --git a/vp9/encoder/vp9_temporal_filter.c b/vp9/encoder/vp9_temporal_filter.c
index ca9339155..498810f6e 100644
--- a/vp9/encoder/vp9_temporal_filter.c
+++ b/vp9/encoder/vp9_temporal_filter.c
@@ -345,33 +345,74 @@ static void temporal_filter_iterate_c(VP9_COMP *cpi,
 void vp9_temporal_filter_prepare(VP9_COMP *cpi, int distance) {
   VP9_COMMON *const cm = &cpi->common;
   int frame = 0;
+  int frames_to_blur_backward = 0;
+  int frames_to_blur_forward = 0;
   int frames_to_blur = 0;
   int start_frame = 0;
   int strength = cpi->active_arnr_strength;
+  int blur_type = cpi->oxcf.arnr_type;
   int max_frames = cpi->active_arnr_frames;
-  int frames_to_blur_backward = distance;
-  int frames_to_blur_forward = vp9_lookahead_depth(cpi->lookahead)
-                                   - (distance + 1);
+  const int num_frames_backward = distance;
+  const int num_frames_forward = vp9_lookahead_depth(cpi->lookahead)
+                               - (num_frames_backward + 1);
   struct scale_factors sf;
 
-  // Determine which input frames to filter.
-  if (frames_to_blur_forward > frames_to_blur_backward)
-    frames_to_blur_forward = frames_to_blur_backward;
+  switch (blur_type) {
+    case 1:
+      // Backward Blur
+      frames_to_blur_backward = num_frames_backward;
 
-  if (frames_to_blur_backward > frames_to_blur_forward)
-    frames_to_blur_backward = frames_to_blur_forward;
+      if (frames_to_blur_backward >= max_frames)
+        frames_to_blur_backward = max_frames - 1;
 
-  // When max_frames is even we have 1 more frame backward than forward
-  if (frames_to_blur_forward > (max_frames - 1) / 2)
-    frames_to_blur_forward = (max_frames - 1) / 2;
+      frames_to_blur = frames_to_blur_backward + 1;
+      break;
 
-  if (frames_to_blur_backward > (max_frames / 2))
-    frames_to_blur_backward = max_frames / 2;
+    case 2:
+      // Forward Blur
+      frames_to_blur_forward = num_frames_forward;
 
-  frames_to_blur = frames_to_blur_backward + frames_to_blur_forward + 1;
+      if (frames_to_blur_forward >= max_frames)
+        frames_to_blur_forward = max_frames - 1;
+
+      frames_to_blur = frames_to_blur_forward + 1;
+      break;
+
+    case 3:
+    default:
+      // Center Blur
+      frames_to_blur_forward = num_frames_forward;
+      frames_to_blur_backward = num_frames_backward;
+
+      if (frames_to_blur_forward > frames_to_blur_backward)
+        frames_to_blur_forward = frames_to_blur_backward;
+
+      if (frames_to_blur_backward > frames_to_blur_forward)
+        frames_to_blur_backward = frames_to_blur_forward;
+
+      // When max_frames is even we have 1 more frame backward than forward
+      if (frames_to_blur_forward > (max_frames - 1) / 2)
+        frames_to_blur_forward = ((max_frames - 1) / 2);
+
+      if (frames_to_blur_backward > (max_frames / 2))
+        frames_to_blur_backward = (max_frames / 2);
+
+      frames_to_blur = frames_to_blur_backward + frames_to_blur_forward + 1;
+      break;
+  }
 
   start_frame = distance + frames_to_blur_forward;
 
+#ifdef DEBUGFWG
+  // DEBUG FWG
+  printf(
+      "max:%d FBCK:%d FFWD:%d ftb:%d ftbbck:%d ftbfwd:%d sei:%d lasei:%d "
+      "start:%d",
+      max_frames, num_frames_backward, num_frames_forward, frames_to_blur,
+      frames_to_blur_backward, frames_to_blur_forward, cpi->source_encode_index,
+      cpi->last_alt_ref_sei, start_frame);
+#endif
+
   // Setup scaling factors. Scaling on each of the arnr frames is not supported
   vp9_setup_scale_factors_for_frame(&sf,
       get_frame_new_buffer(cm)->y_crop_width,
@@ -380,7 +421,7 @@ void vp9_temporal_filter_prepare(VP9_COMP *cpi, int distance) {
 
   // Setup frame pointers, NULL indicates frame not included in filter
   vp9_zero(cpi->frames);
-  for (frame = 0; frame < frames_to_blur; ++frame) {
+  for (frame = 0; frame < frames_to_blur; frame++) {
     int which_buffer = start_frame - frame;
     struct lookahead_entry *buf = vp9_lookahead_peek(cpi->lookahead,
                                                      which_buffer);
@@ -394,11 +435,11 @@ void vp9_temporal_filter_prepare(VP9_COMP *cpi, int distance) {
 void vp9_configure_arnr_filter(VP9_COMP *cpi,
                                const unsigned int frames_to_arnr,
                                const int group_boost) {
-  int q;
   int half_gf_int;
   int frames_after_arf;
-  int frames_bwd;
-  int frames_fwd = (cpi->oxcf.arnr_max_frames - 1) >> 1;
+  int frames_bwd = cpi->oxcf.arnr_max_frames - 1;
+  int frames_fwd = cpi->oxcf.arnr_max_frames - 1;
+  int q;
 
   // Define the arnr filter width for this group of frames. We only
   // filter frames that lie within a distance of half the GF interval
@@ -410,26 +451,47 @@ void vp9_configure_arnr_filter(VP9_COMP *cpi,
   frames_after_arf = vp9_lookahead_depth(cpi->lookahead)
       - frames_to_arnr - 1;
 
-  if (frames_fwd > frames_after_arf)
-    frames_fwd = frames_after_arf;
-  if (frames_fwd > half_gf_int)
-    frames_fwd = half_gf_int;
-
-  frames_bwd = frames_fwd;
-
-  // For even length filter there is one more frame backward
-  // than forward: e.g. len=6 ==> bbbAff, len=7 ==> bbbAfff.
-  if (frames_bwd < half_gf_int)
-    frames_bwd += (cpi->oxcf.arnr_max_frames + 1) & 0x1;
+  switch (cpi->oxcf.arnr_type) {
+    case 1:  // Backward filter
+      frames_fwd = 0;
+      if (frames_bwd > half_gf_int)
+        frames_bwd = half_gf_int;
+      break;
+
+    case 2:  // Forward filter
+      if (frames_fwd > half_gf_int)
+        frames_fwd = half_gf_int;
+      if (frames_fwd > frames_after_arf)
+        frames_fwd = frames_after_arf;
+      frames_bwd = 0;
+      break;
+
+    case 3:  // Centered filter
+    default:
+      frames_fwd >>= 1;
+      if (frames_fwd > frames_after_arf)
+        frames_fwd = frames_after_arf;
+      if (frames_fwd > half_gf_int)
+        frames_fwd = half_gf_int;
+
+      frames_bwd = frames_fwd;
+
+      // For even length filter there is one more frame backward
+      // than forward: e.g. len=6 ==> bbbAff, len=7 ==> bbbAfff.
+      if (frames_bwd < half_gf_int)
+        frames_bwd += (cpi->oxcf.arnr_max_frames + 1) & 0x1;
+      break;
+  }
 
   cpi->active_arnr_frames = frames_bwd + 1 + frames_fwd;
 
   // Adjust the strength based on active max q
   if (cpi->common.current_video_frame > 1)
-    q = ((int)vp9_convert_qindex_to_q(cpi->rc.avg_frame_qindex[INTER_FRAME]));
+    q = ((int)vp9_convert_qindex_to_q(
+        cpi->rc.avg_frame_qindex[INTER_FRAME]));
   else
-    q = ((int)vp9_convert_qindex_to_q(cpi->rc.avg_frame_qindex[KEY_FRAME]));
-
+    q = ((int)vp9_convert_qindex_to_q(
+        cpi->rc.avg_frame_qindex[KEY_FRAME]));
   if (q > 16) {
     cpi->active_arnr_strength = cpi->oxcf.arnr_strength;
   } else {
diff --git a/vp9/vp9_cx_iface.c b/vp9/vp9_cx_iface.c
index 1ca9fb93a..449e7d897 100644
--- a/vp9/vp9_cx_iface.c
+++ b/vp9/vp9_cx_iface.c
@@ -30,6 +30,7 @@ struct vp9_extracfg {
   unsigned int                tile_rows;
   unsigned int                arnr_max_frames;
   unsigned int                arnr_strength;
+  unsigned int                arnr_type;
   vp8e_tuning                 tuning;
   unsigned int                cq_level;  // constrained quality level
   unsigned int                rc_max_intra_bitrate_pct;
@@ -59,6 +60,7 @@ static const struct extraconfig_map extracfg_map[] = {
       0,                          // tile_rows
       7,                          // arnr_max_frames
       5,                          // arnr_strength
+      3,                          // arnr_type
       VP8_TUNE_PSNR,              // tuning
       10,                         // cq_level
       0,                          // rc_max_intra_bitrate_pct
@@ -201,6 +203,7 @@ static vpx_codec_err_t validate_config(vpx_codec_alg_priv_t *ctx,
   RANGE_CHECK_HI(extra_cfg, sharpness, 7);
   RANGE_CHECK(extra_cfg, arnr_max_frames, 0, 15);
   RANGE_CHECK_HI(extra_cfg, arnr_strength, 6);
+  RANGE_CHECK(extra_cfg, arnr_type, 1, 3);
   RANGE_CHECK(extra_cfg, cq_level, 0, 63);
 
   // TODO(yaowu): remove this when ssim tuning is implemented for vp9
@@ -364,6 +367,7 @@ static vpx_codec_err_t set_encoder_config(
 
   oxcf->arnr_max_frames = extra_cfg->arnr_max_frames;
   oxcf->arnr_strength   = extra_cfg->arnr_strength;
+  oxcf->arnr_type       = extra_cfg->arnr_type;
 
   oxcf->tuning = extra_cfg->tuning;
 
@@ -494,6 +498,7 @@ static vpx_codec_err_t ctrl_set_param(vpx_codec_alg_priv_t *ctx, int ctrl_id,
     MAP(VP9E_SET_TILE_ROWS,               extra_cfg.tile_rows);
     MAP(VP8E_SET_ARNR_MAXFRAMES,          extra_cfg.arnr_max_frames);
     MAP(VP8E_SET_ARNR_STRENGTH,           extra_cfg.arnr_strength);
+    MAP(VP8E_SET_ARNR_TYPE,               extra_cfg.arnr_type);
     MAP(VP8E_SET_TUNING,                  extra_cfg.tuning);
     MAP(VP8E_SET_CQ_LEVEL,                extra_cfg.cq_level);
     MAP(VP8E_SET_MAX_INTRA_BITRATE_PCT,   extra_cfg.rc_max_intra_bitrate_pct);
@@ -1107,6 +1112,7 @@ static vpx_codec_ctrl_fn_map_t encoder_ctrl_maps[] = {
   {VP9E_SET_TILE_ROWS,                ctrl_set_param},
   {VP8E_SET_ARNR_MAXFRAMES,           ctrl_set_param},
   {VP8E_SET_ARNR_STRENGTH,            ctrl_set_param},
+  {VP8E_SET_ARNR_TYPE,                ctrl_set_param},
   {VP8E_SET_TUNING,                   ctrl_set_param},
   {VP8E_SET_CQ_LEVEL,                 ctrl_set_param},
   {VP8E_SET_MAX_INTRA_BITRATE_PCT,    ctrl_set_param},
diff --git a/vpx/vp8cx.h b/vpx/vp8cx.h
index 8944a2664..bc8df807e 100644
--- a/vpx/vp8cx.h
+++ b/vpx/vp8cx.h
@@ -160,8 +160,10 @@ enum vp8e_enc_control_id {
                                           scale as used by the rc_*_quantizer config
                                           parameters */
   VP8E_SET_ARNR_MAXFRAMES,         /**< control function to set the max number of frames blurred creating arf*/
-  VP8E_SET_ARNR_STRENGTH,         /**< control function to set the filter strength for the arf */
-  VP8E_SET_ARNR_TYPE,         /**< control function to set the type of filter to use for the arf*/
+  VP8E_SET_ARNR_STRENGTH,          //!< control function to set the filter
+                                   //!< strength for the arf
+  VP8E_SET_ARNR_TYPE,              //!< control function to set the type of
+                                   //!< filter to use for the arf
   VP8E_SET_TUNING,                 /**< control function to set visual tuning */
   /*!\brief control function to set constrained quality level
    *
diff --git a/vpxenc.c b/vpxenc.c
index 3b8591e30..8e8ed2344 100644
--- a/vpxenc.c
+++ b/vpxenc.c
@@ -363,7 +363,7 @@ static const arg_def_t frame_periodic_boost = ARG_DEF(
 
 static const arg_def_t *vp9_args[] = {
   &cpu_used, &auto_altref, &noise_sens, &sharpness, &static_thresh,
-  &tile_cols, &tile_rows, &arnr_maxframes, &arnr_strength,
+  &tile_cols, &tile_rows, &arnr_maxframes, &arnr_strength, &arnr_type,
   &tune_ssim, &cq_level, &max_intra_rate_pct, &lossless,
   &frame_parallel_decoding, &aq_mode, &frame_periodic_boost,
   NULL
@@ -372,7 +372,7 @@ static const int vp9_arg_ctrl_map[] = {
   VP8E_SET_CPUUSED, VP8E_SET_ENABLEAUTOALTREF,
   VP8E_SET_NOISE_SENSITIVITY, VP8E_SET_SHARPNESS, VP8E_SET_STATIC_THRESHOLD,
   VP9E_SET_TILE_COLUMNS, VP9E_SET_TILE_ROWS,
-  VP8E_SET_ARNR_MAXFRAMES, VP8E_SET_ARNR_STRENGTH,
+  VP8E_SET_ARNR_MAXFRAMES, VP8E_SET_ARNR_STRENGTH, VP8E_SET_ARNR_TYPE,
   VP8E_SET_TUNING, VP8E_SET_CQ_LEVEL, VP8E_SET_MAX_INTRA_BITRATE_PCT,
   VP9E_SET_LOSSLESS, VP9E_SET_FRAME_PARALLEL_DECODING, VP9E_SET_AQ_MODE,
   VP9E_SET_FRAME_PERIODIC_BOOST,