commit 31b6a4f9b2c4506f001cca77ff221f0f2d84599f
author Jingning Han <jingning@google.com> Thu Feb 23 11:05:53 2017 -0800
committer Jingning Han <jingning@google.com> Thu Feb 23 20:40:05 2017 +0000
tree 1608670fba9a3c3b003b6099376ea299f9b9735c
parent 282f4111398f4d4044a321970beaa666e58fd68d

Add chroma 2x2 block experiment

Support the use of 2x2 prediction and transform block size for
chroma components. This experiment builds on top of cb4x4. It
brings back the loss in performance gains due to 4x4 chroma
component constrain. The coding gains for lowres are up from 1.5%
to 2.5%.

Change-Id: I8e461e230c2d920f6df1af9d935ebe9dfa3820d9

av1/encoder/encodemb.c

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);

av1/encoder/rdopt.c

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);