commit fcff0b258e29f56cc2d0f0d7b3000b49ab74f2d9
author Rupert Swarbrick <rupert.swarbrick@argondesign.com> Thu Oct 05 09:26:04 2017 +0100
committer Rupert Swarbrick <rupert.swarbrick@argondesign.com> Mon Oct 09 08:42:57 2017 +0000
tree 2bda4a7e7e20589a7372a3152638aff0e295ddc9
parent a3c5b9da51ae009b5169bbf4487086b565b772bc

Define block_signals_txsize function

This returns true if a block signals tx_size in the stream and uses it
in the bitstream writing code and the decoder.

Note that we can't quite use it in pack_inter_mode_mvs when
CONFIG_VAR_TX && !CONFIG_RECT_TX but I've switched the code to using
it the rest of the time since rect-tx is adopted and eventually the
other code path should be deleted.

Also use the helper function in tx_size_cost in rdopt.c, where the
test was wrong and caused underestimates of block
costs. (Specifically, the code that subtracts tx_size_cost from
this_rate_tokenonly in rd_pick_intra_sby_mode ended up subtracting
zero for a 4x8 block).

The behaviour of the decoder should be unchanged. The only change in
the encoder's behaviour should be in tx_size_cost where it should now
match the rest of the code.

Change-Id: I97236c9ce444993afe01ac5c6f4a0bb9e5049217

av1/encoder/bitstream.c

diff --git a/av1/encoder/bitstream.c b/av1/encoder/bitstream.c
index c03db84..515d48e 100644
--- a/av1/encoder/bitstream.c
+++ b/av1/encoder/bitstream.c
@@ -348,12 +348,7 @@
   const BLOCK_SIZE bsize = mbmi->sb_type;
   FRAME_CONTEXT *ec_ctx = xd->tile_ctx;
   (void)cm;
-// For sub8x8 blocks the tx_size symbol does not need to be sent
-#if CONFIG_CB4X4 && (CONFIG_VAR_TX || CONFIG_EXT_TX) && CONFIG_RECT_TX
-  if (bsize > BLOCK_4X4) {
-#else
-  if (bsize >= BLOCK_8X8) {
-#endif
+  if (block_signals_txsize(bsize)) {
     const TX_SIZE tx_size = mbmi->tx_size;
     const int is_inter = is_inter_block(mbmi);
     const TX_SIZE tx_size_ctx = get_tx_size_context(xd);
@@ -1754,14 +1749,10 @@
     write_is_inter(cm, xd, mbmi->segment_id, w, is_inter);
 
   if (cm->tx_mode == TX_MODE_SELECT &&
-#if CONFIG_CB4X4 && (CONFIG_VAR_TX || CONFIG_RECT_TX)
-#if CONFIG_RECT_TX
-      bsize > BLOCK_4X4 &&
-#else
+#if CONFIG_CB4X4 && CONFIG_VAR_TX && !CONFIG_RECT_TX
       (bsize >= BLOCK_8X8 || (bsize > BLOCK_4X4 && is_inter)) &&
-#endif  // CONFIG_RECT_TX
 #else
-      bsize >= BLOCK_8X8 &&
+      block_signals_txsize(bsize) &&
 #endif
 #if CONFIG_SUPERTX
       !supertx_enabled &&
@@ -2157,15 +2148,7 @@
   }
 
   int enable_tx_size = cm->tx_mode == TX_MODE_SELECT &&
-#if CONFIG_CB4X4 && (CONFIG_VAR_TX || CONFIG_RECT_TX)
-#if CONFIG_RECT_TX
-                       bsize > BLOCK_4X4 &&
-#else
-                       bsize >= BLOCK_8X8 &&
-#endif  // CONFIG_RECT_TX
-#else
-                       bsize >= BLOCK_8X8 &&
-#endif
+                       block_signals_txsize(bsize) &&
                        !xd->lossless[mbmi->segment_id];
 
 #if CONFIG_INTRABC