Segment Skip Flag

First step in simplifying the segment mode and
segment EOB flags into a simpler segment skip
flag that implies 0,0 mv and EOB at position 0.

Change-Id: Ib750cac31a7a02dc21082580498efd9f7d8d72a5

6 files changed, 69 insertions, 124 deletions

diff --git a/vp9/encoder/vp9_bitstream.c b/vp9/encoder/vp9_bitstream.c
index 34d27d1be..27d505bce 100644
--- a/vp9/encoder/vp9_bitstream.c
+++ b/vp9/encoder/vp9_bitstream.c
@@ -729,8 +729,7 @@ static void pack_inter_mode_mvs(VP9_COMP *cpi, MODE_INFO *m,
 
   if (!pc->mb_no_coeff_skip) {
     skip_coeff = 0;
-  } else if (vp9_segfeature_active(xd, segment_id, SEG_LVL_EOB) &&
-             vp9_get_segdata(xd, segment_id, SEG_LVL_EOB) == 0) {
+  } else if (vp9_segfeature_active(xd, segment_id, SEG_LVL_SKIP)) {
     skip_coeff = 1;
   } else {
     const int nmbs = mb_size;
@@ -750,24 +749,18 @@ static void pack_inter_mode_mvs(VP9_COMP *cpi, MODE_INFO *m,
   }
 
   // Encode the reference frame.
-  if (!vp9_segfeature_active(xd, segment_id, SEG_LVL_MODE)
-      || vp9_get_segdata(xd, segment_id, SEG_LVL_MODE) >= NEARESTMV) {
-    encode_ref_frame(bc, pc, xd, segment_id, rf);
-  } else {
-    assert(rf == INTRA_FRAME);
-  }
+  encode_ref_frame(bc, pc, xd, segment_id, rf);
 
   if (rf == INTRA_FRAME) {
 #ifdef ENTROPY_STATS
     active_section = 6;
 #endif
 
-    if (!vp9_segfeature_active(xd, segment_id, SEG_LVL_MODE)) {
-      if (m->mbmi.sb_type)
-        write_sb_ymode(bc, mode, pc->fc.sb_ymode_prob);
-      else
-        write_ymode(bc, mode, pc->fc.ymode_prob);
-    }
+    if (m->mbmi.sb_type)
+      write_sb_ymode(bc, mode, pc->fc.sb_ymode_prob);
+    else
+      write_ymode(bc, mode, pc->fc.ymode_prob);
+
     if (mode == B_PRED) {
       int j = 0;
       do {
@@ -798,8 +791,8 @@ static void pack_inter_mode_mvs(VP9_COMP *cpi, MODE_INFO *m,
     active_section = 3;
 #endif
 
-    // Is the segment coding of mode enabled
-    if (!vp9_segfeature_active(xd, segment_id, SEG_LVL_MODE)) {
+    // Is segment skip is not enabled code the mode.
+    if (!vp9_segfeature_active(xd, segment_id, SEG_LVL_SKIP)) {
       if (mi->sb_type) {
         write_sb_mv_ref(bc, mode, mv_ref_p);
       } else {
@@ -942,8 +935,7 @@ static void pack_inter_mode_mvs(VP9_COMP *cpi, MODE_INFO *m,
                                mi->partitioning == PARTITIONING_4X4))) &&
       pc->txfm_mode == TX_MODE_SELECT &&
       !((pc->mb_no_coeff_skip && skip_coeff) ||
-        (vp9_segfeature_active(xd, segment_id, SEG_LVL_EOB) &&
-         vp9_get_segdata(xd, segment_id, SEG_LVL_EOB) == 0))) {
+        (vp9_segfeature_active(xd, segment_id, SEG_LVL_SKIP)))) {
     TX_SIZE sz = mi->txfm_size;
     // FIXME(rbultje) code ternary symbol once all experiments are merged
     vp9_write(bc, sz != TX_4X4, pc->prob_tx[0]);
@@ -972,8 +964,7 @@ static void write_mb_modes_kf(const VP9_COMP *cpi,
 
   if (!c->mb_no_coeff_skip) {
     skip_coeff = 0;
-  } else if (vp9_segfeature_active(xd, segment_id, SEG_LVL_EOB) &&
-             vp9_get_segdata(xd, segment_id, SEG_LVL_EOB) == 0) {
+  } else if (vp9_segfeature_active(xd, segment_id, SEG_LVL_SKIP)) {
     skip_coeff = 1;
   } else {
     const int nmbs = 1 << m->mbmi.sb_type;
@@ -1032,8 +1023,7 @@ static void write_mb_modes_kf(const VP9_COMP *cpi,
 
   if (ym <= I8X8_PRED && c->txfm_mode == TX_MODE_SELECT &&
       !((c->mb_no_coeff_skip && skip_coeff) ||
-        (vp9_segfeature_active(xd, segment_id, SEG_LVL_EOB) &&
-         vp9_get_segdata(xd, segment_id, SEG_LVL_EOB) == 0))) {
+        (vp9_segfeature_active(xd, segment_id, SEG_LVL_SKIP)))) {
     TX_SIZE sz = m->mbmi.txfm_size;
     // FIXME(rbultje) code ternary symbol once all experiments are merged
     vp9_write(bc, sz != TX_4X4, c->prob_tx[0]);
diff --git a/vp9/encoder/vp9_encodeframe.c b/vp9/encoder/vp9_encodeframe.c
index 8a4b7e662..b26c60b03 100644
--- a/vp9/encoder/vp9_encodeframe.c
+++ b/vp9/encoder/vp9_encodeframe.c
@@ -488,8 +488,7 @@ static void update_state(VP9_COMP *cpi,
 
   {
     int segment_id = mbmi->segment_id;
-    if (!vp9_segfeature_active(xd, segment_id, SEG_LVL_EOB) ||
-        vp9_get_segdata(xd, segment_id, SEG_LVL_EOB)) {
+    if (!vp9_segfeature_active(xd, segment_id, SEG_LVL_SKIP)) {
       for (i = 0; i < NB_TXFM_MODES; i++) {
         cpi->rd_tx_select_diff[i] += ctx->txfm_rd_diff[i];
       }
@@ -1392,8 +1391,7 @@ static void reset_skip_txfm_size_mb(VP9_COMP *cpi,
     const int segment_id = mbmi->segment_id;
 
     xd->mode_info_context = mi;
-    assert((vp9_segfeature_active(xd, segment_id, SEG_LVL_EOB) &&
-            vp9_get_segdata(xd, segment_id, SEG_LVL_EOB) == 0) ||
+    assert((vp9_segfeature_active(xd, segment_id, SEG_LVL_SKIP)) ||
            (cm->mb_no_coeff_skip && mbmi->mb_skip_coeff));
     mbmi->txfm_size = txfm_max;
   }
@@ -1437,8 +1435,7 @@ static void reset_skip_txfm_size_sb32(VP9_COMP *cpi, MODE_INFO *mi,
     const int xmbs = MIN(2, mb_cols_left);
 
     xd->mode_info_context = mi;
-    assert((vp9_segfeature_active(xd, segment_id, SEG_LVL_EOB) &&
-            vp9_get_segdata(xd, segment_id, SEG_LVL_EOB) == 0) ||
+    assert((vp9_segfeature_active(xd, segment_id, SEG_LVL_SKIP)) ||
            (cm->mb_no_coeff_skip && get_skip_flag(mi, mis, ymbs, xmbs)));
     set_txfm_flag(mi, mis, ymbs, xmbs, txfm_max);
   }
@@ -1458,8 +1455,7 @@ static void reset_skip_txfm_size_sb64(VP9_COMP *cpi, MODE_INFO *mi,
     const int xmbs = MIN(4, mb_cols_left);
 
     xd->mode_info_context = mi;
-    assert((vp9_segfeature_active(xd, segment_id, SEG_LVL_EOB) &&
-            vp9_get_segdata(xd, segment_id, SEG_LVL_EOB) == 0) ||
+    assert((vp9_segfeature_active(xd, segment_id, SEG_LVL_SKIP)) ||
            (cm->mb_no_coeff_skip && get_skip_flag(mi, mis, ymbs, xmbs)));
     set_txfm_flag(mi, mis, ymbs, xmbs, txfm_max);
   }
@@ -2231,8 +2227,7 @@ static void encode_macroblock(VP9_COMP *cpi, TOKENEXTRA **t,
     int segment_id = mbmi->segment_id;
     if (cpi->common.txfm_mode == TX_MODE_SELECT &&
         !((cpi->common.mb_no_coeff_skip && mbmi->mb_skip_coeff) ||
-          (vp9_segfeature_active(&x->e_mbd, segment_id, SEG_LVL_EOB) &&
-           vp9_get_segdata(&x->e_mbd, segment_id, SEG_LVL_EOB) == 0))) {
+          (vp9_segfeature_active(&x->e_mbd, segment_id, SEG_LVL_SKIP)))) {
       assert(mbmi->txfm_size <= TX_16X16);
       if (mbmi->mode != B_PRED && mbmi->mode != I8X8_PRED &&
           mbmi->mode != SPLITMV) {
@@ -2469,8 +2464,7 @@ static void encode_superblock32(VP9_COMP *cpi, TOKENEXTRA **t,
   if (output_enabled) {
     if (cm->txfm_mode == TX_MODE_SELECT &&
         !((cm->mb_no_coeff_skip && skip[0] && skip[1] && skip[2] && skip[3]) ||
-          (vp9_segfeature_active(xd, segment_id, SEG_LVL_EOB) &&
-           vp9_get_segdata(xd, segment_id, SEG_LVL_EOB) == 0))) {
+          (vp9_segfeature_active(xd, segment_id, SEG_LVL_SKIP)))) {
       cpi->txfm_count_32x32p[mi->mbmi.txfm_size]++;
     } else {
       TX_SIZE sz = (cm->txfm_mode == TX_MODE_SELECT) ?
@@ -2733,8 +2727,7 @@ static void encode_superblock64(VP9_COMP *cpi, TOKENEXTRA **t,
              skip[4] && skip[5] && skip[6] && skip[7] &&
              skip[8] && skip[9] && skip[10] && skip[11] &&
              skip[12] && skip[13] && skip[14] && skip[15]))) ||
-          (vp9_segfeature_active(xd, segment_id, SEG_LVL_EOB) &&
-           vp9_get_segdata(xd, segment_id, SEG_LVL_EOB) == 0))) {
+          (vp9_segfeature_active(xd, segment_id, SEG_LVL_SKIP)))) {
       cpi->txfm_count_32x32p[mi->mbmi.txfm_size]++;
     } else {
       int x, y;
diff --git a/vp9/encoder/vp9_onyx_if.c b/vp9/encoder/vp9_onyx_if.c
index a14165752..878844683 100644
--- a/vp9/encoder/vp9_onyx_if.c
+++ b/vp9/encoder/vp9_onyx_if.c
@@ -446,7 +446,7 @@ static void init_seg_features(VP9_COMP *cpi) {
   else if (xd->segmentation_enabled) {
     // First normal frame in a valid gf or alt ref group
     if (cpi->common.frames_since_golden == 0) {
-      // Set up segment features for normal frames in an af group
+      // Set up segment features for normal frames in an arf group
       if (cpi->source_alt_ref_active) {
         xd->update_mb_segmentation_map = 0;
         xd->update_mb_segmentation_data = 1;
@@ -463,16 +463,9 @@ static void init_seg_features(VP9_COMP *cpi) {
 
         // Segment coding disabled for compred testing
         if (high_q || (cpi->static_mb_pct == 100)) {
-          // set_segref(xd, 1, LAST_FRAME);
           vp9_set_segref(xd, 1, ALTREF_FRAME);
           vp9_enable_segfeature(xd, 1, SEG_LVL_REF_FRAME);
-
-          vp9_set_segdata(xd, 1, SEG_LVL_MODE, ZEROMV);
-          vp9_enable_segfeature(xd, 1, SEG_LVL_MODE);
-
-          // EOB segment coding not fixed for 8x8 yet
-          vp9_set_segdata(xd, 1, SEG_LVL_EOB, 0);
-          vp9_enable_segfeature(xd, 1, SEG_LVL_EOB);
+          vp9_enable_segfeature(xd, 1, SEG_LVL_SKIP);
         }
       }
       // Disable segmentation and clear down features if alt ref
@@ -491,29 +484,23 @@ static void init_seg_features(VP9_COMP *cpi) {
     }
 
     // Special case where we are coding over the top of a previous
-    // alt ref frame
+    // alt ref frame.
     // Segment coding disabled for compred testing
     else if (cpi->is_src_frame_alt_ref) {
-      // Enable mode and ref frame features for segment 0 as well
+      // Enable ref frame features for segment 0 as well
       vp9_enable_segfeature(xd, 0, SEG_LVL_REF_FRAME);
-      vp9_enable_segfeature(xd, 0, SEG_LVL_MODE);
       vp9_enable_segfeature(xd, 1, SEG_LVL_REF_FRAME);
-      vp9_enable_segfeature(xd, 1, SEG_LVL_MODE);
 
-      // All mbs should use ALTREF_FRAME, ZEROMV exclusively
+      // All mbs should use ALTREF_FRAME
       vp9_clear_segref(xd, 0);
       vp9_set_segref(xd, 0, ALTREF_FRAME);
       vp9_clear_segref(xd, 1);
       vp9_set_segref(xd, 1, ALTREF_FRAME);
-      vp9_set_segdata(xd, 0, SEG_LVL_MODE, ZEROMV);
-      vp9_set_segdata(xd, 1, SEG_LVL_MODE, ZEROMV);
 
-      // Skip all MBs if high Q
+      // Skip all MBs if high Q (0,0 mv and skip coeffs)
       if (high_q) {
-        vp9_enable_segfeature(xd, 0, SEG_LVL_EOB);
-        vp9_set_segdata(xd, 0, SEG_LVL_EOB, 0);
-        vp9_enable_segfeature(xd, 1, SEG_LVL_EOB);
-        vp9_set_segdata(xd, 1, SEG_LVL_EOB, 0);
+          vp9_enable_segfeature(xd, 0, SEG_LVL_SKIP);
+          vp9_enable_segfeature(xd, 1, SEG_LVL_SKIP);
       }
       // Enable data udpate
       xd->update_mb_segmentation_data = 1;
diff --git a/vp9/encoder/vp9_quantize.c b/vp9/encoder/vp9_quantize.c
index 2f0a55a8a..f5a2f38e8 100644
--- a/vp9/encoder/vp9_quantize.c
+++ b/vp9/encoder/vp9_quantize.c
@@ -556,16 +556,12 @@ void vp9_mb_init_quantizer(VP9_COMP *cpi, MACROBLOCK *x) {
     x->block[i].zrun_zbin_boost = cpi->zrun_zbin_boost_y1[QIndex];
     x->block[i].zbin_extra = (int16_t)zbin_extra;
 
-    // Segment max eob offset feature.
-    if (vp9_segfeature_active(xd, segment_id, SEG_LVL_EOB)) {
-      x->block[i].eob_max_offset =
-        vp9_get_segdata(xd, segment_id, SEG_LVL_EOB);
-      x->block[i].eob_max_offset_8x8 =
-        vp9_get_segdata(xd, segment_id, SEG_LVL_EOB);
-      x->block[i].eob_max_offset_16x16 =
-        vp9_get_segdata(xd, segment_id, SEG_LVL_EOB);
-      x->block[i].eob_max_offset_32x32 =
-      vp9_get_segdata(xd, segment_id, SEG_LVL_EOB);
+    // Segment skip feature.
+    if (vp9_segfeature_active(xd, segment_id, SEG_LVL_SKIP)) {
+      x->block[i].eob_max_offset = 0;
+      x->block[i].eob_max_offset_8x8 = 0;
+      x->block[i].eob_max_offset_16x16 = 0;
+      x->block[i].eob_max_offset_32x32 = 0;
     } else {
       x->block[i].eob_max_offset = 16;
       x->block[i].eob_max_offset_8x8 = 64;
@@ -590,14 +586,11 @@ void vp9_mb_init_quantizer(VP9_COMP *cpi, MACROBLOCK *x) {
 
     x->block[i].zbin_extra = (int16_t)zbin_extra;
 
-    // Segment max eob offset feature.
-    if (vp9_segfeature_active(xd, segment_id, SEG_LVL_EOB)) {
-      x->block[i].eob_max_offset =
-        vp9_get_segdata(xd, segment_id, SEG_LVL_EOB);
-      x->block[i].eob_max_offset_8x8 =
-        vp9_get_segdata(xd, segment_id, SEG_LVL_EOB);
-      x->block[i].eob_max_offset_16x16 =
-      vp9_get_segdata(xd, segment_id, SEG_LVL_EOB);
+    // Segment skip feature.
+    if (vp9_segfeature_active(xd, segment_id, SEG_LVL_SKIP)) {
+      x->block[i].eob_max_offset = 0;
+      x->block[i].eob_max_offset_8x8 = 0;
+      x->block[i].eob_max_offset_16x16 = 0;
     } else {
       x->block[i].eob_max_offset = 16;
       x->block[i].eob_max_offset_8x8 = 64;
@@ -620,12 +613,10 @@ void vp9_mb_init_quantizer(VP9_COMP *cpi, MACROBLOCK *x) {
   x->block[24].zbin_extra = (int16_t)zbin_extra;
 
   // TBD perhaps not use for Y2
-  // Segment max eob offset feature.
-  if (vp9_segfeature_active(xd, segment_id, SEG_LVL_EOB)) {
-    x->block[24].eob_max_offset =
-      vp9_get_segdata(xd, segment_id, SEG_LVL_EOB);
-    x->block[24].eob_max_offset_8x8 =
-      vp9_get_segdata(xd, segment_id, SEG_LVL_EOB);
+  // Segment skip feature.
+  if (vp9_segfeature_active(xd, segment_id, SEG_LVL_SKIP)) {
+    x->block[24].eob_max_offset = 0;
+    x->block[24].eob_max_offset_8x8 = 0;
   } else {
     x->block[24].eob_max_offset = 16;
     x->block[24].eob_max_offset_8x8 = 4;
diff --git a/vp9/encoder/vp9_rdopt.c b/vp9/encoder/vp9_rdopt.c
index f860e94ca..45c72bcc5 100644
--- a/vp9/encoder/vp9_rdopt.c
+++ b/vp9/encoder/vp9_rdopt.c
@@ -498,8 +498,8 @@ static int cost_coeffs(MACROBLOCK *mb,
   pn = pt;
 #endif
 
-  if (vp9_segfeature_active(xd, segment_id, SEG_LVL_EOB))
-    seg_eob = vp9_get_segdata(xd, segment_id, SEG_LVL_EOB);
+  if (vp9_segfeature_active(xd, segment_id, SEG_LVL_SKIP))
+    seg_eob = 0;
 
   if (tx_type != DCT_DCT) {
     for (; c < eob; c++) {
@@ -2082,12 +2082,8 @@ int vp9_cost_mv_ref(VP9_COMP *cpi,
   MACROBLOCKD *xd = &cpi->mb.e_mbd;
   int segment_id = xd->mode_info_context->mbmi.segment_id;
 
-  // If the mode coding is done entirely at the segment level
-  // we should not account for it at the per mb level in rd code.
-  // Note that if the segment level coding is expanded from single mode
-  // to multiple mode masks as per reference frame coding we will need
-  // to do something different here.
-  if (!vp9_segfeature_active(xd, segment_id, SEG_LVL_MODE)) {
+  // Dont account for mode here if segment skip is enabled.
+  if (!vp9_segfeature_active(xd, segment_id, SEG_LVL_SKIP)) {
     VP9_COMMON *pc = &cpi->common;
 
     vp9_prob p [VP9_MVREFS - 1];
@@ -3695,18 +3691,16 @@ static void rd_pick_inter_mode(VP9_COMP *cpi, MACROBLOCK *x,
     if (vp9_segfeature_active(xd, segment_id, SEG_LVL_REF_FRAME) &&
         !vp9_check_segref(xd, segment_id, mbmi->ref_frame)) {
       continue;
-    // If the segment mode feature is enabled....
+    // If the segment skip feature is enabled....
     // then do nothing if the current mode is not allowed..
-    } else if (vp9_segfeature_active(xd, segment_id, SEG_LVL_MODE) &&
-               (this_mode !=
-                vp9_get_segdata(xd, segment_id, SEG_LVL_MODE))) {
+    } else if (vp9_segfeature_active(xd, segment_id, SEG_LVL_SKIP) &&
+               (this_mode != ZEROMV)) {
       continue;
-    // Disable this drop out case if either the mode or ref frame
-    // segment level feature is enabled for this segment. This is to
+    // Disable this drop out case if  the ref frame segment
+    // level feature is enabled for this segment. This is to
     // prevent the possibility that the we end up unable to pick any mode.
-    } else if (!vp9_segfeature_active(xd, segment_id, SEG_LVL_REF_FRAME) &&
-               !vp9_segfeature_active(xd, segment_id, SEG_LVL_MODE)) {
-      // Only consider ZEROMV/ALTREF_FRAME for alt ref frame,
+    } else if (!vp9_segfeature_active(xd, segment_id, SEG_LVL_REF_FRAME)) {
+      // Only consider ZEROMV/ALTREF_FRAME for alt ref frame overlay,
       // unless ARNR filtering is enabled in which case we want
       // an unfiltered alternative
       if (cpi->is_src_frame_alt_ref && (cpi->oxcf.arnr_max_frames == 0)) {
@@ -3997,10 +3991,8 @@ static void rd_pick_inter_mode(VP9_COMP *cpi, MACROBLOCK *x,
       if (cpi->common.mb_no_coeff_skip) {
         int mb_skip_allowed;
 
-        // Is Mb level skip allowed for this mb.
-        mb_skip_allowed =
-          !vp9_segfeature_active(xd, segment_id, SEG_LVL_EOB) ||
-          vp9_get_segdata(xd, segment_id, SEG_LVL_EOB);
+        // Is Mb level skip allowed (i.e. not coded at segment level).
+        mb_skip_allowed = !vp9_segfeature_active(xd, segment_id, SEG_LVL_SKIP);
 
         if (skippable) {
           mbmi->mb_skip_coeff = 1;
@@ -4206,12 +4198,11 @@ static void rd_pick_inter_mode(VP9_COMP *cpi, MACROBLOCK *x,
         cpi->rd_thresh_mult[best_mode_index];
   }
 
-  // This code force Altref,0,0 and skip for the frame that overlays a
+  // This code forces Altref,0,0 and skip for the frame that overlays a
   // an alrtef unless Altref is filtered. However, this is unsafe if
-  // segment level coding of ref frame or mode is enabled for this
+  // segment level coding of ref frame is enabled for this
   // segment.
   if (!vp9_segfeature_active(xd, segment_id, SEG_LVL_REF_FRAME) &&
-      !vp9_segfeature_active(xd, segment_id, SEG_LVL_MODE) &&
       cpi->is_src_frame_alt_ref &&
       (cpi->oxcf.arnr_max_frames == 0) &&
       (best_mbmode.mode != ZEROMV || best_mbmode.ref_frame != ALTREF_FRAME)) {
@@ -4675,16 +4666,15 @@ static int64_t vp9_rd_pick_inter_mode_sb(VP9_COMP *cpi, MACROBLOCK *x,
     if (vp9_segfeature_active(xd, segment_id, SEG_LVL_REF_FRAME) &&
         !vp9_check_segref(xd, segment_id, ref_frame)) {
       continue;
-    // If the segment mode feature is enabled....
+    // If the segment skip feature is enabled....
     // then do nothing if the current mode is not allowed..
-    } else if (vp9_segfeature_active(xd, segment_id, SEG_LVL_MODE) &&
-               (this_mode != vp9_get_segdata(xd, segment_id, SEG_LVL_MODE))) {
+    } else if (vp9_segfeature_active(xd, segment_id, SEG_LVL_SKIP) &&
+               (this_mode != ZEROMV)) {
       continue;
-    // Disable this drop out case if either the mode or ref frame
+    // Disable this drop out case if the ref frame
     // segment level feature is enabled for this segment. This is to
     // prevent the possibility that we end up unable to pick any mode.
-    } else if (!vp9_segfeature_active(xd, segment_id, SEG_LVL_REF_FRAME) &&
-               !vp9_segfeature_active(xd, segment_id, SEG_LVL_MODE)) {
+    } else if (!vp9_segfeature_active(xd, segment_id, SEG_LVL_REF_FRAME)) {
       // Only consider ZEROMV/ALTREF_FRAME for alt ref frame,
       // unless ARNR filtering is enabled in which case we want
       // an unfiltered alternative
@@ -4773,10 +4763,8 @@ static int64_t vp9_rd_pick_inter_mode_sb(VP9_COMP *cpi, MACROBLOCK *x,
       if (cpi->common.mb_no_coeff_skip) {
         int mb_skip_allowed;
 
-        // Is Mb level skip allowed for this mb.
-        mb_skip_allowed =
-          !vp9_segfeature_active(xd, segment_id, SEG_LVL_EOB) ||
-          vp9_get_segdata(xd, segment_id, SEG_LVL_EOB);
+        // Is Mb level skip allowed (i.e. not coded at segment level).
+        mb_skip_allowed = !vp9_segfeature_active(xd, segment_id, SEG_LVL_SKIP);
 
         if (skippable) {
           // Back out the coefficient coding costs
@@ -4960,10 +4948,8 @@ static int64_t vp9_rd_pick_inter_mode_sb(VP9_COMP *cpi, MACROBLOCK *x,
 
   // This code forces Altref,0,0 and skip for the frame that overlays a
   // an alrtef unless Altref is filtered. However, this is unsafe if
-  // segment level coding of ref frame or mode is enabled for this
-  // segment.
+  // segment level coding of ref frame is enabled for this segment.
   if (!vp9_segfeature_active(xd, segment_id, SEG_LVL_REF_FRAME) &&
-      !vp9_segfeature_active(xd, segment_id, SEG_LVL_MODE) &&
       cpi->is_src_frame_alt_ref &&
       (cpi->oxcf.arnr_max_frames == 0) &&
       (best_mbmode.mode != ZEROMV || best_mbmode.ref_frame != ALTREF_FRAME)) {
diff --git a/vp9/encoder/vp9_tokenize.c b/vp9/encoder/vp9_tokenize.c
index fc99311ae..0d444b80d 100644
--- a/vp9/encoder/vp9_tokenize.c
+++ b/vp9/encoder/vp9_tokenize.c
@@ -233,8 +233,8 @@ static void tokenize_b(VP9_COMP *cpi,
   pn = pt;
 #endif
 
-  if (vp9_segfeature_active(xd, segment_id, SEG_LVL_EOB))
-    seg_eob = vp9_get_segdata(xd, segment_id, SEG_LVL_EOB);
+  if (vp9_segfeature_active(xd, segment_id, SEG_LVL_SKIP))
+    seg_eob = 0;
 
   do {
     const int band = bands[c];
@@ -390,8 +390,7 @@ void vp9_tokenize_sb(VP9_COMP *cpi,
                             (ENTROPY_CONTEXT *) (xd->left_context + 1), };
   const int mb_skip_context = vp9_get_pred_context(cm, xd, PRED_MBSKIP);
   const int segment_id = mbmi->segment_id;
-  const int skip_inc =  !vp9_segfeature_active(xd, segment_id, SEG_LVL_EOB) ||
-                        (vp9_get_segdata(xd, segment_id, SEG_LVL_EOB) != 0);
+  const int skip_inc = !vp9_segfeature_active(xd, segment_id, SEG_LVL_SKIP);
   int b;
 
   mbmi->mb_skip_coeff = sb_is_skippable_32x32(xd);
@@ -441,8 +440,7 @@ void vp9_tokenize_mb(VP9_COMP *cpi,
   int skip_inc;
   int segment_id = xd->mode_info_context->mbmi.segment_id;
 
-  if (!vp9_segfeature_active(xd, segment_id, SEG_LVL_EOB) ||
-      (vp9_get_segdata(xd, segment_id, SEG_LVL_EOB) != 0)) {
+  if (!vp9_segfeature_active(xd, segment_id, SEG_LVL_SKIP)) {
     skip_inc = 1;
   } else
     skip_inc = 0;