diff --git a/av1/encoder/tx_search.c b/av1/encoder/tx_search.c
index d7333b3..b6294e6 100644
--- a/av1/encoder/tx_search.c
+++ b/av1/encoder/tx_search.c
@@ -2151,7 +2151,7 @@
     }
 #endif  // CONFIG_ATC_REDUCED_TXSET
 #if CONFIG_ATC_DCTX_ALIGNED
-    if (tx_size == TX_32X32) ext_tx_used_flag |= (1 << IDTX);
+    if (txsize_sqr_up_map[tx_size] == TX_32X32) ext_tx_used_flag |= (1 << IDTX);
 #endif  // CONFIG_ATC_DCTX_ALIGNED
   }
 #if CONFIG_ATC_REDUCED_TXSET