Add iLBC codec

git-svn-id: http://svn.digium.com/svn/asterisk/trunk@852 f38db490-d61c-443f-a65b-d21fe96a405b

1 files changed, 104 insertions, 0 deletions

diff --git a/codecs/ilbc/iCBConstruct.c b/codecs/ilbc/iCBConstruct.c
new file mode 100755
index 000000000..ccb3f663b
--- /dev/null
+++ b/codecs/ilbc/iCBConstruct.c
@@ -0,0 +1,104 @@
+ 
+/****************************************************************** 
+ 
+    iLBC Speech Coder ANSI-C Source Code 
+ 
+    iCBConstruct.c  
+ 
+    Copyright (c) 2001, 
+    Global IP Sound AB. 
+    All rights reserved. 
+ 
+******************************************************************/ 
+ 
+#include <math.h> 
+ 
+#include "iLBC_define.h" 
+#include "gainquant.h" 
+#include "getCBvec.h" 
+ 
+/*----------------------------------------------------------------* 
+ *  Convert the codebook indexes to make the search easier 
+ *---------------------------------------------------------------*/ 
+ 
+void index_conv_enc( 
+    int *index          /* (i/o) Codebook indexes */ 
+){ 
+    int k; 
+ 
+    for (k=1;k<CB_NSTAGES;k++) { 
+         
+        if ((index[k]>=108)&&(index[k]<172)) { 
+            index[k]-=64; 
+        } else if (index[k]>=236) { 
+            index[k]-=128; 
+        } else { 
+            /* ERROR */ 
+        } 
+    } 
+} 
+ 
+void index_conv_dec( 
+    int *index          /* (i/o) Codebook indexes */ 
+){ 
+    int k; 
+ 
+    for (k=1;k<CB_NSTAGES;k++) { 
+         
+        if ((index[k]>=44)&&(index[k]<108)) { 
+            index[k]+=64; 
+        } else if ((index[k]>=108)&&(index[k]<128)) { 
+            index[k]+=128; 
+        } else { 
+            /* ERROR */ 
+        } 
+    } 
+} 
+ 
+/*----------------------------------------------------------------* 
+ *  Construct decoded vector from codebook and gains. 
+ *---------------------------------------------------------------*/ 
+ 
+void iCBConstruct( 
+    float *decvector,   /* (o) Decoded vector */ 
+    int *index,         /* (i) Codebook indices */ 
+    int *gain_index,/* (i) Gain quantization indices */ 
+    float *mem,         /* (i) Buffer for codevector construction */ 
+    int lMem,           /* (i) Length of buffer */ 
+    int veclen,         /* (i) Length of vector */ 
+    int nStages         /* (i) Number of codebook stages */ 
+){ 
+    int j,k; 
+    float gain[CB_NSTAGES]; 
+    float cbvec[SUBL]; 
+ 
+    /* gain de-quantization */ 
+ 
+    gain[0] = gaindequant(gain_index[0], 1.0, 32); 
+    if (nStages > 1) { 
+        gain[1] = gaindequant(gain_index[1],  
+            (float)fabs(gain[0]), 16);   
+    } 
+    if (nStages > 2) { 
+        gain[2] = gaindequant(gain_index[2],  
+            (float)fabs(gain[1]), 8); 
+    } 
+ 
+    /* codebook vector construction and construction of  
+    total vector */ 
+ 
+    getCBvec(cbvec, mem, index[0], lMem, veclen); 
+    for (j=0;j<veclen;j++){ 
+        decvector[j] = gain[0]*cbvec[j]; 
+    } 
+    if (nStages > 1) { 
+        for (k=1; k<nStages; k++) { 
+            getCBvec(cbvec, mem, index[k], lMem, veclen); 
+            for (j=0;j<veclen;j++) { 
+                decvector[j] += gain[k]*cbvec[j]; 
+            } 
+        } 
+    } 
+} 
+ 
+