libvpx: Pull from upstream

source/libvpx/vp9/encoder/vp9_aq_cyclicrefresh.c

 /*
  *  Copyright (c) 2014 The WebM project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 21 matching lines @@
   int time_for_refresh;
   // Target number of (8x8) blocks that are set for delta-q.
   int target_num_seg_blocks;
   // Actual number of (8x8) blocks that were applied delta-q.
   int actual_num_seg1_blocks;
   int actual_num_seg2_blocks;
   // RD mult. parameters for segment 1.
   int rdmult;
   // Cyclic refresh map.
   signed char *map;
+  // Map of the last q a block was coded at.
+  uint8_t *last_coded_q_map;
   // Thresholds applied to the projected rate/distortion of the coding block,
   // when deciding whether block should be refreshed.
   int64_t thresh_rate_sb;
   int64_t thresh_dist_sb;
   // Threshold applied to the motion vector (in units of 1/8 pel) of the
   // coding block, when deciding whether block should be refreshed.
   int16_t motion_thresh;
   // Rate target ratio to set q delta.
   double rate_ratio_qdelta;
+  // Boost factor for rate target ratio, for segment CR_SEGMENT_ID_BOOST2.
+  int rate_boost_fac;
   double low_content_avg;
-  int qindex_delta_seg1;
-  int qindex_delta_seg2;
+  int qindex_delta[3];
 };
 
 CYCLIC_REFRESH *vp9_cyclic_refresh_alloc(int mi_rows, int mi_cols) {
+  size_t last_coded_q_map_size;
   CYCLIC_REFRESH *const cr = vpx_calloc(1, sizeof(*cr));
   if (cr == NULL)
     return NULL;
 
   cr->map = vpx_calloc(mi_rows * mi_cols, sizeof(*cr->map));
   if (cr->map == NULL) {
     vpx_free(cr);
     return NULL;
   }
+  last_coded_q_map_size = mi_rows * mi_cols * sizeof(*cr->last_coded_q_map);
+  cr->last_coded_q_map = vpx_malloc(last_coded_q_map_size);
+  if (cr->last_coded_q_map == NULL) {
+    vpx_free(cr);
+    return NULL;
+  }
+  assert(MAXQ <= 255);
+  memset(cr->last_coded_q_map, MAXQ, last_coded_q_map_size);
 
   return cr;
 }
 
 void vp9_cyclic_refresh_free(CYCLIC_REFRESH *cr) {
   vpx_free(cr->map);
+  vpx_free(cr->last_coded_q_map);
   vpx_free(cr);
 }
 
 // Check if we should turn off cyclic refresh based on bitrate condition.
 static int apply_cyclic_refresh_bitrate(const VP9_COMMON *cm,
                                         const RATE_CONTROL *rc) {
   // Turn off cyclic refresh if bits available per frame is not sufficiently
   // larger than bit cost of segmentation. Segment map bit cost should scale
   // with number of seg blocks, so compare available bits to number of blocks.
   // Average bits available per frame = avg_frame_bandwidth
@@ skipping 27 matching lines @@
   // 2) mode is an intra-mode
   // Otherwise accept for refresh.
   if (dist > cr->thresh_dist_sb &&
       (mv.row > cr->motion_thresh || mv.row < -cr->motion_thresh ||
        mv.col > cr->motion_thresh || mv.col < -cr->motion_thresh ||
        !is_inter_block(mbmi)))
     return CR_SEGMENT_ID_BASE;
   else  if (bsize >= BLOCK_16X16 &&
             rate < cr->thresh_rate_sb &&
             is_inter_block(mbmi) &&
-            mbmi->mv[0].as_int == 0)
+            mbmi->mv[0].as_int == 0 &&
+            cr->rate_boost_fac > 10)
     // More aggressive delta-q for bigger blocks with zero motion.
     return CR_SEGMENT_ID_BOOST2;
   else
     return CR_SEGMENT_ID_BOOST1;
 }
 
 // Compute delta-q for the segment.
 static int compute_deltaq(const VP9_COMP *cpi, int q, double rate_factor) {
   const CYCLIC_REFRESH *const cr = cpi->cyclic_refresh;
   const RATE_CONTROL *const rc = &cpi->rc;
@@ skipping 20 matching lines @@
   // Weight for non-base segments: use actual number of blocks refreshed in
   // previous/just encoded frame. Note number of blocks here is in 8x8 units.
   double weight_segment1 = (double)cr->actual_num_seg1_blocks / num8x8bl;
   double weight_segment2 = (double)cr->actual_num_seg2_blocks / num8x8bl;
   // Take segment weighted average for estimated bits.
   estimated_bits = (int)((1.0 - weight_segment1 - weight_segment2) *
       vp9_estimate_bits_at_q(cm->frame_type, cm->base_qindex, mbs,
                              correction_factor, cm->bit_depth) +
                              weight_segment1 *
       vp9_estimate_bits_at_q(cm->frame_type,
-                             cm->base_qindex + cr->qindex_delta_seg1, mbs,
+                             cm->base_qindex + cr->qindex_delta[1], mbs,
                              correction_factor, cm->bit_depth) +
                              weight_segment2 *
       vp9_estimate_bits_at_q(cm->frame_type,
-                             cm->base_qindex + cr->qindex_delta_seg2, mbs,
+                             cm->base_qindex + cr->qindex_delta[2], mbs,
                              correction_factor, cm->bit_depth));
   return estimated_bits;
 }
 
 // Prior to encoding the frame, estimate the bits per mb, for a given q = i and
 // a corresponding delta-q (for segment 1). This function is called in the
 // rc_regulate_q() to set the base qp index.
 // Note: the segment map is set to either 0/CR_SEGMENT_ID_BASE (no refresh) or
 // to 1/CR_SEGMENT_ID_BOOST1 (refresh) for each superblock, prior to encoding.
 int vp9_cyclic_refresh_rc_bits_per_mb(const VP9_COMP *cpi, int i,
@@ skipping 64 matching lines @@
       new_map_value = 0;
   } else {
     // Leave it marked as block that is not candidate for refresh.
     new_map_value = 1;
   }
 
   // Update entries in the cyclic refresh map with new_map_value, and
   // copy mbmi->segment_id into global segmentation map.
   for (y = 0; y < ymis; y++)
     for (x = 0; x < xmis; x++) {
-      cr->map[block_index + y * cm->mi_cols + x] = new_map_value;
-      cpi->segmentation_map[block_index + y * cm->mi_cols + x] =
-          mbmi->segment_id;
+      int map_offset = block_index + y * cm->mi_cols + x;
+      cr->map[map_offset] = new_map_value;
+      cpi->segmentation_map[map_offset] = mbmi->segment_id;
+      // Inter skip blocks were clearly not coded at the current qindex, so
+      // don't update the map for them. For cases where motion is non-zero or
+      // the reference frame isn't the previous frame, the previous value in
+      // the map for this spatial location is not entirely correct.
+      if (!is_inter_block(mbmi) || !skip)
+        cr->last_coded_q_map[map_offset] = clamp(
+            cm->base_qindex + cr->qindex_delta[mbmi->segment_id], 0, MAXQ);
     }
 }
 
 // Update the actual number of blocks that were applied the segment delta q.
 void vp9_cyclic_refresh_postencode(VP9_COMP *const cpi) {
   VP9_COMMON *const cm = &cpi->common;
   CYCLIC_REFRESH *const cr = cpi->cyclic_refresh;
   unsigned char *const seg_map = cpi->segmentation_map;
   int mi_row, mi_col;
   cr->actual_num_seg1_blocks = 0;
@@ skipping 113 matching lines @@
   assert(cr->sb_index < sbs_in_frame);
   i = cr->sb_index;
   cr->target_num_seg_blocks = 0;
   do {
     int sum_map = 0;
     // Get the mi_row/mi_col corresponding to superblock index i.
     int sb_row_index = (i / sb_cols);
     int sb_col_index = i - sb_row_index * sb_cols;
     int mi_row = sb_row_index * MI_BLOCK_SIZE;
     int mi_col = sb_col_index * MI_BLOCK_SIZE;
+    int qindex_thresh =
+        cpi->oxcf.content == VP9E_CONTENT_SCREEN
+            ? vp9_get_qindex(&cm->seg, CR_SEGMENT_ID_BOOST2, cm->base_qindex)
+            : 0;
     assert(mi_row >= 0 && mi_row < cm->mi_rows);
     assert(mi_col >= 0 && mi_col < cm->mi_cols);
     bl_index = mi_row * cm->mi_cols + mi_col;
     // Loop through all 8x8 blocks in superblock and update map.
     xmis = MIN(cm->mi_cols - mi_col,
                num_8x8_blocks_wide_lookup[BLOCK_64X64]);
     ymis = MIN(cm->mi_rows - mi_row,
                num_8x8_blocks_high_lookup[BLOCK_64X64]);
     for (y = 0; y < ymis; y++) {
       for (x = 0; x < xmis; x++) {
         const int bl_index2 = bl_index + y * cm->mi_cols + x;
         // If the block is as a candidate for clean up then mark it
         // for possible boost/refresh (segment 1). The segment id may get
         // reset to 0 later if block gets coded anything other than ZEROMV.
         if (cr->map[bl_index2] == 0) {
-          sum_map++;
+          if (cr->last_coded_q_map[bl_index2] > qindex_thresh)
+            sum_map++;
         } else if (cr->map[bl_index2] < 0) {
           cr->map[bl_index2]++;
         }
       }
     }
     // Enforce constant segment over superblock.
     // If segment is at least half of superblock, set to 1.
     if (sum_map >= xmis * ymis / 2) {
       for (y = 0; y < ymis; y++)
         for (x = 0; x < xmis; x++) {
           seg_map[bl_index + y * cm->mi_cols + x] = CR_SEGMENT_ID_BOOST1;
         }
       cr->target_num_seg_blocks += xmis * ymis;
     }
     i++;
     if (i == sbs_in_frame) {
       i = 0;
     }
   } while (cr->target_num_seg_blocks < block_count && i != cr->sb_index);
   cr->sb_index = i;
 }
 
-// Set/update global/frame level cyclic refresh parameters.
+// Set cyclic refresh parameters.
 void vp9_cyclic_refresh_update_parameters(VP9_COMP *const cpi) {
   const RATE_CONTROL *const rc = &cpi->rc;
+  const VP9_COMMON *const cm = &cpi->common;
   CYCLIC_REFRESH *const cr = cpi->cyclic_refresh;
   cr->percent_refresh = 10;
+  cr->max_qdelta_perc = 50;
+  cr->time_for_refresh = 0;
   // Use larger delta-qp (increase rate_ratio_qdelta) for first few (~4)
-  // periods of the refresh cycle, after a key frame. This corresponds to ~40
-  // frames with cr->percent_refresh = 10.
-  if (rc->frames_since_key <  40)
+  // periods of the refresh cycle, after a key frame.
+  if (rc->frames_since_key <  4 * cr->percent_refresh)
     cr->rate_ratio_qdelta = 3.0;
   else
     cr->rate_ratio_qdelta = 2.0;
+  // Adjust some parameters for low resolutions at low bitrates.
+  if (cm->width <= 352 &&
+      cm->height <= 288 &&
+      rc->avg_frame_bandwidth < 3400) {
+    cr->motion_thresh = 4;
+    cr->rate_boost_fac = 10;
+  } else {
+    cr->motion_thresh = 32;
+    cr->rate_boost_fac = 17;
+  }
 }
 
 // Setup cyclic background refresh: set delta q and segmentation map.
 void vp9_cyclic_refresh_setup(VP9_COMP *const cpi) {
   VP9_COMMON *const cm = &cpi->common;
   const RATE_CONTROL *const rc = &cpi->rc;
   CYCLIC_REFRESH *const cr = cpi->cyclic_refresh;
   struct segmentation *const seg = &cm->seg;
   const int apply_cyclic_refresh  = apply_cyclic_refresh_bitrate(cm, rc);
   if (cm->current_video_frame == 0)
     cr->low_content_avg = 0.0;
   // Don't apply refresh on key frame or enhancement layer frames.
   if (!apply_cyclic_refresh ||
       (cm->frame_type == KEY_FRAME) ||
       (cpi->svc.temporal_layer_id > 0) ||
       (cpi->svc.spatial_layer_id > 0)) {
     // Set segmentation map to 0 and disable.
     unsigned char *const seg_map = cpi->segmentation_map;
     memset(seg_map, 0, cm->mi_rows * cm->mi_cols);
     vp9_disable_segmentation(&cm->seg);
-    if (cm->frame_type == KEY_FRAME)
+    if (cm->frame_type == KEY_FRAME) {
+      memset(cr->last_coded_q_map, MAXQ,
+             cm->mi_rows * cm->mi_cols * sizeof(*cr->last_coded_q_map));
       cr->sb_index = 0;
+    }
     return;
   } else {
     int qindex_delta = 0;
     int qindex2;
     const double q = vp9_convert_qindex_to_q(cm->base_qindex, cm->bit_depth);
     vp9_clear_system_state();
-    cr->max_qdelta_perc = 50;
-    cr->time_for_refresh = 0;
     // Set rate threshold to some multiple (set to 2 for now) of the target
     // rate (target is given by sb64_target_rate and scaled by 256).
     cr->thresh_rate_sb = ((int64_t)(rc->sb64_target_rate) << 8) << 2;
     // Distortion threshold, quadratic in Q, scale factor to be adjusted.
     // q will not exceed 457, so (q * q) is within 32bit; see:
     // vp9_convert_qindex_to_q(), vp9_ac_quant(), ac_qlookup*[].
     cr->thresh_dist_sb = ((int64_t)(q * q)) << 2;
-    cr->motion_thresh = 32;
+
     // Set up segmentation.
     // Clear down the segment map.
     vp9_enable_segmentation(&cm->seg);
     vp9_clearall_segfeatures(seg);
     // Select delta coding method.
     seg->abs_delta = SEGMENT_DELTADATA;
 
     // Note: setting temporal_update has no effect, as the seg-map coding method
     // (temporal or spatial) is determined in vp9_choose_segmap_coding_method(),
     // based on the coding cost of each method. For error_resilient mode on the
     // last_frame_seg_map is set to 0, so if temporal coding is used, it is
     // relative to 0 previous map.
     // seg->temporal_update = 0;
 
     // Segment BASE "Q" feature is disabled so it defaults to the baseline Q.
     vp9_disable_segfeature(seg, CR_SEGMENT_ID_BASE, SEG_LVL_ALT_Q);
     // Use segment BOOST1 for in-frame Q adjustment.
     vp9_enable_segfeature(seg, CR_SEGMENT_ID_BOOST1, SEG_LVL_ALT_Q);
     // Use segment BOOST2 for more aggressive in-frame Q adjustment.
     vp9_enable_segfeature(seg, CR_SEGMENT_ID_BOOST2, SEG_LVL_ALT_Q);
 
     // Set the q delta for segment BOOST1.
     qindex_delta = compute_deltaq(cpi, cm->base_qindex, cr->rate_ratio_qdelta);
-    cr->qindex_delta_seg1 = qindex_delta;
+    cr->qindex_delta[1] = qindex_delta;
 
     // Compute rd-mult for segment BOOST1.
     qindex2 = clamp(cm->base_qindex + cm->y_dc_delta_q + qindex_delta, 0, MAXQ);
 
     cr->rdmult = vp9_compute_rd_mult(cpi, qindex2);
 
     vp9_set_segdata(seg, CR_SEGMENT_ID_BOOST1, SEG_LVL_ALT_Q, qindex_delta);
 
     // Set a more aggressive (higher) q delta for segment BOOST2.
-    qindex_delta = compute_deltaq(cpi, cm->base_qindex,
-                                  MIN(CR_MAX_RATE_TARGET_RATIO,
-                                      CR_BOOST2_FAC * cr->rate_ratio_qdelta));
-    cr->qindex_delta_seg2 = qindex_delta;
+    qindex_delta = compute_deltaq(
+        cpi, cm->base_qindex, MIN(CR_MAX_RATE_TARGET_RATIO,
+        0.1 * cr->rate_boost_fac * cr->rate_ratio_qdelta));
+    cr->qindex_delta[2] = qindex_delta;
     vp9_set_segdata(seg, CR_SEGMENT_ID_BOOST2, SEG_LVL_ALT_Q, qindex_delta);
 
     // Update the segmentation and refresh map.
     cyclic_refresh_update_map(cpi);
   }
 }
 
 int vp9_cyclic_refresh_get_rdmult(const CYCLIC_REFRESH *cr) {
   return cr->rdmult;
 }
+
+void vp9_cyclic_refresh_reset_resize(VP9_COMP *const cpi) {
+  const VP9_COMMON *const cm = &cpi->common;
+  CYCLIC_REFRESH *const cr = cpi->cyclic_refresh;
+  memset(cr->map, 0, cm->mi_rows * cm->mi_cols);
+  cr->sb_index = 0;
+}