optimisation of 8-16kHz funcs

git-svn-id: https://svn.code.sf.net/p/freetel/code@1812 01035d8c-6547-0410-b346-abe4f91aad63

diff --git a/codec2-dev/src/fdmdv.c b/codec2-dev/src/fdmdv.c
index fd0f35544c6a42570936075b32ffe33ce3d6c3a2..b57887e588ef3adadbc1000a29a4039b1456bb6e 100644 (file)
--- a/codec2-dev/src/fdmdv.c
+++ b/codec2-dev/src/fdmdv.c
@@ -1716,21 +1716,28 @@ void fdmdv_get_demod_stats(struct FDMDV *fdmdv, struct FDMDV_STATS *fdmdv_stats)
 
 void fdmdv_8_to_16(float out16k[], float in8k[], int n)
 {
-    int i,j,k,l;
+    int i,k,l;
+    float acc;
 
     /* make sure n is an integer multiple of the oversampling rate, ow
        this function breaks */
 
     assert((n % FDMDV_OS) == 0);
 
+    /* this version unrolled for specific FDMDV_OS */
+
+    assert(FDMDV_OS == 2);
+    
     for(i=0; i<n; i++) {
-       for(j=0; j<FDMDV_OS; j++) {
-           out16k[i*FDMDV_OS+j] = 0.0;
-           for(k=0,l=0; k<FDMDV_OS_TAPS_16K; k+=FDMDV_OS,l++)
-               out16k[i*FDMDV_OS+j] += fdmdv_os_filter[k+j]*in8k[i-l];
-           out16k[i*FDMDV_OS+j] *= FDMDV_OS;
-           
-       }
+        acc = 0.0;
+        for(k=0,l=0; k<FDMDV_OS_TAPS_16K; k+=FDMDV_OS,l++)
+            acc += fdmdv_os_filter[k]*in8k[i-l];
+        out16k[i*FDMDV_OS] = FDMDV_OS*acc;
+
+        acc = 0.0;
+        for(k=1,l=0; k<FDMDV_OS_TAPS_16K; k+=FDMDV_OS,l++)
+            acc += fdmdv_os_filter[k]*in8k[i-l];
+        out16k[i*FDMDV_OS+1] = FDMDV_OS*acc;
     }  
 
     /* update filter memory */
@@ -1742,7 +1749,7 @@ void fdmdv_8_to_16(float out16k[], float in8k[], int n)
 
 void fdmdv_8_to_16_short(short out16k[], short in8k[], int n)
 {
-    int i,j,k,l;
+    int i,k,l;
     float acc;
 
     /* make sure n is an integer multiple of the oversampling rate, ow
@@ -1750,14 +1757,20 @@ void fdmdv_8_to_16_short(short out16k[], short in8k[], int n)
 
     assert((n % FDMDV_OS) == 0);
 
+    /* this version unrolled for specific FDMDV_OS */
+
+    assert(FDMDV_OS == 2);
+
     for(i=0; i<n; i++) {
-       for(j=0; j<FDMDV_OS; j++) {
-           acc = 0.0;
-           for(k=0,l=0; k<FDMDV_OS_TAPS_16K; k+=FDMDV_OS,l++)
-               acc += fdmdv_os_filter[k+j]*(float)in8k[i-l];
-           out16k[i*FDMDV_OS+j] = acc*FDMDV_OS;
-           
-       }
+        acc = 0.0;
+        for(k=0,l=0; k<FDMDV_OS_TAPS_16K; k+=FDMDV_OS,l++)
+            acc += fdmdv_os_filter[k]*(float)in8k[i-l];
+        out16k[i*FDMDV_OS] = FDMDV_OS*acc;
+
+        acc = 0.0;
+        for(k=1,l=0; k<FDMDV_OS_TAPS_16K; k+=FDMDV_OS,l++)
+            acc += fdmdv_os_filter[k]*(float)in8k[i-l];
+        out16k[i*FDMDV_OS+1] = FDMDV_OS*acc;
     }  
 
     /* update filter memory */
@@ -1789,11 +1802,10 @@ void fdmdv_16_to_8(float out8k[], float in16k[], int n)
     float acc;
     int   i,j,k;
     
-    for(i=0, k=0; k<n; i+=FDMDV_OS, k++) {
-        
+    for(i=0, k=0; k<n; i+=FDMDV_OS, k++) {       
        acc = 0.0;
        for(j=0; j<FDMDV_OS_TAPS_16K; j++)
-           acc += fdmdv_os_filter[j]*(float)in16k[i-j]; 
+           acc += fdmdv_os_filter[j]*in16k[i-j]; 
         out8k[k] = acc;       
     }
 
@@ -1805,12 +1817,14 @@ void fdmdv_16_to_8(float out8k[], float in16k[], int n)
 
 void fdmdv_16_to_8_short(short out8k[], short in16k[], int n)
 {
-    int i,j;
+    float acc;
+    int i,j,k;
 
-    for(i=0; i<n; i++) {
-       out8k[i] = 0.0;
+    for(i=0, k=0; k<n; i+=FDMDV_OS, k++) {
+       acc = 0.0;
        for(j=0; j<FDMDV_OS_TAPS_16K; j++)
-           out8k[i] += fdmdv_os_filter[j]*(float)in16k[i*FDMDV_OS-j];
+           acc += fdmdv_os_filter[j]*(float)in16k[i-j];
+        out8k[k] = acc;
     }
 
     /* update filter memory */