diff --git a/av1/common/blockd.c b/av1/common/blockd.c
index a0342db..a689b81 100644
--- a/av1/common/blockd.c
+++ b/av1/common/blockd.c
@@ -130,7 +130,7 @@
   // 4x4=0, 8x8=2, 16x16=4, 32x32=6, 64x64=8
   // transform size varies per plane, look it up in a common way.
   const TX_SIZE tx_size = plane ? get_uv_tx_size(mbmi, pd) : mbmi->tx_size;
-#if CONFIG_CB4X4
+#if CONFIG_CB4X4 && !CONFIG_CHROMA_2X2
   const BLOCK_SIZE plane_bsize =
       AOMMAX(BLOCK_4X4, get_plane_block_size(bsize, pd));
 #else
diff --git a/av1/common/blockd.h b/av1/common/blockd.h
index 950e564..a79cd08 100644
--- a/av1/common/blockd.h
+++ b/av1/common/blockd.h
@@ -924,7 +924,7 @@
 
   uv_txsize = uv_txsize_lookup[mbmi->sb_type][mbmi->tx_size][pd->subsampling_x]
                               [pd->subsampling_y];
-#if CONFIG_CB4X4
+#if CONFIG_CB4X4 && !CONFIG_CHROMA_2X2
   uv_txsize = AOMMAX(uv_txsize, TX_4X4);
 #endif
   assert(uv_txsize != TX_INVALID);
diff --git a/av1/common/onyxc_int.h b/av1/common/onyxc_int.h
index fd70332..6bb0ce3 100644
--- a/av1/common/onyxc_int.h
+++ b/av1/common/onyxc_int.h
@@ -585,8 +585,10 @@
     xd->plane[i].width = (bw * MI_SIZE) >> xd->plane[i].subsampling_x;
     xd->plane[i].height = (bh * MI_SIZE) >> xd->plane[i].subsampling_y;
 
+#if !CONFIG_CHROMA_2X2
     xd->plane[i].width = AOMMAX(xd->plane[i].width, 4);
     xd->plane[i].height = AOMMAX(xd->plane[i].height, 4);
+#endif
   }
 }
 
@@ -728,6 +730,9 @@
 
 #if CONFIG_CB4X4
 static INLINE int is_chroma_reference(const int mi_row, const int mi_col) {
+#if CONFIG_CHROMA_2X2
+  return 1;
+#endif
   return !((mi_row & 0x01) || (mi_col & 0x01));
 }
 #endif
diff --git a/av1/common/reconintra.c b/av1/common/reconintra.c
index 367efdd..bdb9e5e 100644
--- a/av1/common/reconintra.c
+++ b/av1/common/reconintra.c
@@ -1895,7 +1895,7 @@
   const int mi_col = -xd->mb_to_left_edge >> (3 + MI_SIZE_LOG2);
   const int txwpx = tx_size_wide[tx_size];
   const int txhpx = tx_size_high[tx_size];
-#if CONFIG_CB4X4
+#if CONFIG_CB4X4 && !CONFIG_CHROMA_2X2
   const int xr_chr_offset = (plane && bsize < BLOCK_8X8) ? 2 : 0;
   const int yd_chr_offset = (plane && bsize < BLOCK_8X8) ? 2 : 0;
 #else
@@ -1918,7 +1918,7 @@
   const PARTITION_TYPE partition = xd->mi[0]->mbmi.partition;
 #endif
 
-#if CONFIG_CB4X4
+#if CONFIG_CB4X4 && !CONFIG_CHROMA_2X2
   // force 4x4 chroma component block size.
   if (plane && bsize < BLOCK_8X8) bsize = BLOCK_8X8;
 #endif
diff --git a/av1/decoder/decodeframe.c b/av1/decoder/decodeframe.c
index b9cb37a..8447606 100644
--- a/av1/decoder/decodeframe.c
+++ b/av1/decoder/decodeframe.c
@@ -1659,8 +1659,12 @@
       const int stepr = tx_size_high_unit[tx_size];
       const int stepc = tx_size_wide_unit[tx_size];
 #if CONFIG_CB4X4
+#if CONFIG_CHROMA_2X2
+      const BLOCK_SIZE plane_bsize = get_plane_block_size(bsize, pd);
+#else
       const BLOCK_SIZE plane_bsize =
           AOMMAX(BLOCK_4X4, get_plane_block_size(bsize, pd));
+#endif  // CONFIG_CHROMA_2X2
 #else
       const BLOCK_SIZE plane_bsize =
           get_plane_block_size(AOMMAX(BLOCK_8X8, bsize), pd);
@@ -1744,8 +1748,12 @@
       for (plane = 0; plane < MAX_MB_PLANE; ++plane) {
         const struct macroblockd_plane *const pd = &xd->plane[plane];
 #if CONFIG_CB4X4
+#if CONFIG_CHROMA_2X2
+        const BLOCK_SIZE plane_bsize = get_plane_block_size(bsize, pd);
+#else
         const BLOCK_SIZE plane_bsize =
             AOMMAX(BLOCK_4X4, get_plane_block_size(bsize, pd));
+#endif  // CONFIG_CHROMA_2X2
 #else
         const BLOCK_SIZE plane_bsize =
             get_plane_block_size(AOMMAX(BLOCK_8X8, bsize), pd);
diff --git a/av1/encoder/encodemb.c b/av1/encoder/encodemb.c
index 567cf01..12a0004 100644
--- a/av1/encoder/encodemb.c
+++ b/av1/encoder/encodemb.c
@@ -887,7 +887,7 @@
   if (x->skip) return;
 
   for (plane = 0; plane < MAX_MB_PLANE; ++plane) {
-#if CONFIG_CB4X4
+#if CONFIG_CB4X4 && !CONFIG_CHROMA_2X2
     if (bsize < BLOCK_8X8 && plane && !is_chroma_reference(mi_row, mi_col))
       continue;
     if (plane) bsize = AOMMAX(bsize, BLOCK_8X8);
diff --git a/av1/encoder/rdopt.c b/av1/encoder/rdopt.c
index 54a3225..bf6c94c 100644
--- a/av1/encoder/rdopt.c
+++ b/av1/encoder/rdopt.c
@@ -974,7 +974,7 @@
   for (plane = plane_from; plane <= plane_to; ++plane) {
     struct macroblock_plane *const p = &x->plane[plane];
     struct macroblockd_plane *const pd = &xd->plane[plane];
-#if CONFIG_CB4X4
+#if CONFIG_CB4X4 && !CONFIG_CHROMA_2X2
     const BLOCK_SIZE bs = AOMMAX(BLOCK_4X4, get_plane_block_size(bsize, pd));
 #else
     const BLOCK_SIZE bs = get_plane_block_size(bsize, pd);
@@ -3721,7 +3721,7 @@
 
   if (ref_best_rd < 0) is_cost_valid = 0;
 
-#if CONFIG_CB4X4
+#if CONFIG_CB4X4 && !CONFIG_CHROMA_2X2
   if (x->skip_chroma_rd) return is_cost_valid;
   bsize = AOMMAX(BLOCK_8X8, bsize);
 #endif
@@ -4347,7 +4347,7 @@
 
   av1_init_rd_stats(rd_stats);
 
-#if CONFIG_CB4X4
+#if CONFIG_CB4X4 && !CONFIG_CHROMA_2X2
   if (x->skip_chroma_rd) return is_cost_valid;
   bsize = AOMMAX(BLOCK_8X8, bsize);
 #endif
@@ -4845,6 +4845,10 @@
   // appropriate speed flag is set.
   (void)ctx;
 #if CONFIG_CB4X4
+#if CONFIG_CHROMA_2X2
+  rd_pick_intra_sbuv_mode(cpi, x, rate_uv, rate_uv_tokenonly, dist_uv, skip_uv,
+                          bsize, max_tx_size);
+#else
   max_tx_size = AOMMAX(max_tx_size, TX_4X4);
   if (x->skip_chroma_rd) {
     *rate_uv = 0;
@@ -4854,10 +4858,13 @@
     *mode_uv = DC_PRED;
     return;
   }
-#endif
-
   rd_pick_intra_sbuv_mode(cpi, x, rate_uv, rate_uv_tokenonly, dist_uv, skip_uv,
                           bsize < BLOCK_8X8 ? BLOCK_8X8 : bsize, max_tx_size);
+#endif  // CONFIG_CHROMA_2X2
+#else
+  rd_pick_intra_sbuv_mode(cpi, x, rate_uv, rate_uv_tokenonly, dist_uv, skip_uv,
+                          bsize < BLOCK_8X8 ? BLOCK_8X8 : bsize, max_tx_size);
+#endif  // CONFIG_CB4X4
   *mode_uv = x->e_mbd.mi[0]->mbmi.uv_mode;
 }
 
@@ -9059,7 +9066,9 @@
                                    [pd[1].subsampling_x][pd[1].subsampling_y];
 
 #if CONFIG_CB4X4
+#if !CONFIG_CHROMA_2X2
   max_uv_tx_size = AOMMAX(max_uv_tx_size, TX_4X4);
+#endif
   if (!x->skip_chroma_rd)
     rd_pick_intra_sbuv_mode(cpi, x, &rate_uv, &rate_uv_tokenonly, &dist_uv,
                             &uv_skip, bsize, max_uv_tx_size);