1 files changed, 183 insertions, 0 deletions
diff --git a/opencore/codecs_v2/audio/gsm_amr/amr_nb/enc/src/lflg_upd.cpp b/opencore/codecs_v2/audio/gsm_amr/amr_nb/enc/src/lflg_upd.cpp
new file mode 100644
index 0000000..0e2e5bd
--- /dev/null
+++ b/opencore/codecs_v2/audio/gsm_amr/amr_nb/enc/src/lflg_upd.cpp
@@ -0,0 +1,183 @@
+/* ------------------------------------------------------------------
+ * Copyright (C) 1998-2009 PacketVideo
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
+ * express or implied.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ * -------------------------------------------------------------------
+ */
+/****************************************************************************************
+Portions of this file are derived from the following 3GPP standard:
+
+    3GPP TS 26.073
+    ANSI-C code for the Adaptive Multi-Rate (AMR) speech codec
+    Available from http://www.3gpp.org
+
+(C) 2004, 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TTA, TTC)
+Permission to distribute, modify and use this file under the standard license
+terms listed above has been obtained from the copyright holder.
+****************************************************************************************/
+/*
+
+ Filename: lflg_upd.cpp
+ Functions: LTP_flag_update
+
+------------------------------------------------------------------------------
+ MODULE DESCRIPTION
+
+ LTP_flag update for AMR VAD option 2
+------------------------------------------------------------------------------
+*/
+
+/*----------------------------------------------------------------------------
+; INCLUDES
+----------------------------------------------------------------------------*/
+#include "typedef.h"
+#include "cnst.h"
+#include "l_extract.h"
+#include "mpy_32_16.h"
+
+#include "vad2.h"
+#include "mode.h"
+
+/*----------------------------------------------------------------------------
+; MACROS
+; Define module specific macros here
+----------------------------------------------------------------------------*/
+
+/*----------------------------------------------------------------------------
+; DEFINES
+; Include all pre-processor statements here. Include conditional
+; compile variables also.
+----------------------------------------------------------------------------*/
+
+/*----------------------------------------------------------------------------
+; LOCAL FUNCTION DEFINITIONS
+; Function Prototype declaration
+----------------------------------------------------------------------------*/
+
+/*----------------------------------------------------------------------------
+; LOCAL VARIABLE DEFINITIONS
+; Variable declaration - defined here and used outside this module
+----------------------------------------------------------------------------*/
+
+
+/*
+------------------------------------------------------------------------------
+ FUNCTION NAME:
+------------------------------------------------------------------------------
+ INPUT AND OUTPUT DEFINITIONS
+
+ Inputs:
+    st -- Pointer to vadState2
+    mode -- Word16 -- AMR mode
+
+ Outputs:
+    st -- Pointer to vadState2
+    pOverflow -- Pointer to Flag -- overflow indicator
+
+ Returns:
+    None
+
+ Global Variables Used:
+    None
+
+ Local Variables Needed:
+    None
+
+------------------------------------------------------------------------------
+ FUNCTION DESCRIPTION
+
+ LTP_flag update for AMR VAD option 2
+
+
+ PURPOSE:
+   Set LTP_flag if the LTP gain > LTP_THRESHOLD, where the value of
+   LTP_THRESHOLD depends on the LTP analysis window length.
+
+ INPUTS:
+
+   mode
+                   AMR mode
+   vadState->L_R0
+                   LTP energy
+   vadState->L_Rmax
+                   LTP maximum autocorrelation
+ OUTPUTS:
+
+   vadState->LTP_flag
+                   Set if LTP gain > LTP_THRESHOLD
+
+ RETURN VALUE:
+
+   none
+
+
+------------------------------------------------------------------------------
+ REQUIREMENTS
+
+ None
+
+------------------------------------------------------------------------------
+ REFERENCES
+
+ lflg_upd.c, UMTS GSM AMR speech codec, R99 - Version 3.2.0, March 2, 2001
+
+------------------------------------------------------------------------------
+ PSEUDO-CODE
+
+
+------------------------------------------------------------------------------
+ CAUTION [optional]
+ [State any special notes, constraints or cautions for users of this function]
+
+------------------------------------------------------------------------------
+*/
+
+void LTP_flag_update(
+    vadState2 * st,
+    Word16 mode,
+    Flag   *pOverflow)
+{
+    Word16 thresh;
+    Word16 hi1;
+    Word16 lo1;
+    Word32 Ltmp;
+
+    if ((mode == MR475) || (mode == MR515))
+    {
+        thresh = 18022; /* (Word16)(32768.0*0.55); */
+    }
+    else if (mode == MR102)
+    {
+        thresh = 19660; /* (Word16)(32768.0*0.60); */
+    }
+    else
+    {
+        thresh = 21299; /* (Word16)(32768.0*0.65); */
+    }
+
+    L_Extract(st->L_R0, &hi1, &lo1, pOverflow);
+
+    Ltmp = Mpy_32_16(hi1, lo1, thresh, pOverflow);
+
+    if (st->L_Rmax > Ltmp)
+    {
+        st->LTP_flag = TRUE;
+    }
+    else
+    {
+        st->LTP_flag = FALSE;
+    }
+
+    return;
+}