From 35e1bceea3cca657955475033fe2b5b5fbd6892f Mon Sep 17 00:00:00 2001
From: vaclav <vaclav.eksler@usherbrooke.ca>
Date: Wed, 13 Nov 2024 11:14:47 +0100
Subject: [PATCH] issue 1203: fix severe artifacts during MDCT to DFT stereo
 switching when MDCT ITD is not used; under NONBE_1203_MDCT2DFT_SWITCHING

---
 lib_com/options.h                   |  2 +-
 lib_enc/ivas_stereo_dft_td_itd.c    | 14 ++++++++++++++
 lib_enc/ivas_stereo_switching_enc.c |  3 +++
 3 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/lib_com/options.h b/lib_com/options.h
index 0d18daf5ea..90ea6c62b1 100644
--- a/lib_com/options.h
+++ b/lib_com/options.h
@@ -183,7 +183,7 @@
 
 
 #define NONBE_1200_ISM_JBM_BRATE_SW_FLUSH               /* VA: issue 1200: fix bug in renderer flush in ISM JBM bitrate switching */
-
+#define NONBE_1203_MDCT2DFT_SWITCHING                   /* VA: issue 1203: fix severe artifacts during MDCT to DFT stereo switching when MDCT ITD is not used */
 
 /* ##################### End NON-BE switches ########################### */
 
diff --git a/lib_enc/ivas_stereo_dft_td_itd.c b/lib_enc/ivas_stereo_dft_td_itd.c
index 3e635f68e7..bab1b1d6fd 100755
--- a/lib_enc/ivas_stereo_dft_td_itd.c
+++ b/lib_enc/ivas_stereo_dft_td_itd.c
@@ -399,6 +399,9 @@ void stereo_td_itd_mdct_stereo(
     float bin_nrgR[STEREO_DFT_N_32k_ENC];
     float DFT[CPE_CHANNELS][STEREO_DFT_N_MAX_ENC];
     STEREO_MDCT_ENC_DATA_HANDLE hStereoMdct;
+#ifdef NONBE_1203_MDCT2DFT_SWITCHING
+    int16_t dft_ovl;
+#endif
 
     if ( hCPE->hStereoMdct != NULL && hCPE->hStereoMdct->hItd != NULL )
     {
@@ -427,6 +430,17 @@ void stereo_td_itd_mdct_stereo(
         stereo_td_itd( hStereoMdct->hItd, NULL, 1, hStereoMdct->hDft_ana->dft_ovl, hCPE->hCoreCoder, input_frame, hCPE->input_mem );
 #endif
     }
+#ifdef NONBE_1203_MDCT2DFT_SWITCHING
+    else if ( hCPE->input_mem[0] != NULL )
+    {
+        dft_ovl = STEREO_DFT_OVL_MAX * input_frame / L_FRAME48k;
+
+        for ( i = 0; i < CPE_CHANNELS; i++ )
+        {
+            mvr2r( hCPE->hCoreCoder[i]->input + input_frame - dft_ovl, hCPE->input_mem[i], dft_ovl );
+        }
+    }
+#endif
 
     return;
 }
diff --git a/lib_enc/ivas_stereo_switching_enc.c b/lib_enc/ivas_stereo_switching_enc.c
index 8bbfd39321..d5cf09e509 100644
--- a/lib_enc/ivas_stereo_switching_enc.c
+++ b/lib_enc/ivas_stereo_switching_enc.c
@@ -625,6 +625,9 @@ void stereo_switching_enc(
     dft_ovl = STEREO_DFT_OVL_MAX * input_frame / L_FRAME48k;
 
     /* update DFT analysis overlap memory */
+#ifdef NONBE_1203_MDCT2DFT_SWITCHING
+    /* note: in MDCT stereo, the update is done in stereo_td_itd_mdct_stereo() */
+#endif
     if ( hCPE->element_mode > IVAS_CPE_DFT && hCPE->input_mem[0] != NULL && hCPE->element_mode != IVAS_CPE_MDCT )
     {
         for ( n = 0; n < CPE_CHANNELS; n++ )
-- 
GitLab