1 files changed, 173 insertions, 181 deletions

diff --git a/lsp.c b/lsp.c
index 05d190e..aa7bac3 100644
--- a/lsp.c
+++ b/lsp.c
@@ -28,12 +28,14 @@
   along with this program; if not, see <http://www.gnu.org/licenses/>.
 */
 
-#include "defines.h"
 #include "lsp.h"
+
 #include <math.h>
 #include <stdio.h>
 #include <stdlib.h>
 
+#include "defines.h"
+
 /*---------------------------------------------------------------------------*\
 
   Introduction to Line Spectrum Pairs (LSPs)
@@ -77,49 +79,45 @@
   AUTHOR......: David Rowe
   DATE CREATED: 24/2/93
 
-  This function evalutes a series of chebyshev polynomials
+  This function evaluates a series of chebyshev polynomials
 
   FIXME: performing memory allocation at run time is very inefficient,
   replace with stack variables of MAX_P size.
 
 \*---------------------------------------------------------------------------*/
 
-
-static float
-cheb_poly_eva(float *coef,float x,int order)
+static float cheb_poly_eva(float *coef, float x, int order)
 /*  float coef[]        coefficients of the polynomial to be evaluated  */
 /*  float x             the point where polynomial is to be evaluated   */
 /*  int order           order of the polynomial                         */
 {
-    int i;
-    float *t,*u,*v,sum;
-    float T[(order / 2) + 1];
+  int i;
+  float *t, *u, *v, sum;
+  float T[(order / 2) + 1];
 
-    /* Initialise pointers */
+  /* Initialise pointers */
 
-    t = T;                              /* T[i-2]                       */
-    *t++ = 1.0;
-    u = t--;                            /* T[i-1]                       */
-    *u++ = x;
-    v = u--;                            /* T[i]                         */
+  t = T; /* T[i-2]                      */
+  *t++ = 1.0;
+  u = t--; /* T[i-1]                    */
+  *u++ = x;
+  v = u--; /* T[i]                      */
 
-    /* Evaluate chebyshev series formulation using iterative approach   */
+  /* Evaluate chebyshev series formulation using iterative approach     */
 
-    for(i=2;i<=order/2;i++)
-        *v++ = (2*x)*(*u++) - *t++;     /* T[i] = 2*x*T[i-1] - T[i-2]   */
+  for (i = 2; i <= order / 2; i++)
+    *v++ = (2 * x) * (*u++) - *t++; /* T[i] = 2*x*T[i-1] - T[i-2]       */
 
-    sum=0.0;                            /* initialise sum to zero       */
-    t = T;                              /* reset pointer                */
+  sum = 0.0; /* initialise sum to zero  */
+  t = T;     /* reset pointer           */
 
-    /* Evaluate polynomial and return value also free memory space */
+  /* Evaluate polynomial and return value also free memory space */
 
-    for(i=0;i<=order/2;i++)
-        sum+=coef[(order/2)-i]**t++;
+  for (i = 0; i <= order / 2; i++) sum += coef[(order / 2) - i] * *t++;
 
-    return sum;
+  return sum;
 }
 
-
 /*---------------------------------------------------------------------------*\
 
   FUNCTION....: lpc_to_lsp()
@@ -130,121 +128,118 @@ cheb_poly_eva(float *coef,float x,int order)
 
 \*---------------------------------------------------------------------------*/
 
-int lpc_to_lsp (float *a, int order, float *freq, int nb, float delta)
+int lpc_to_lsp(float *a, int order, float *freq, int nb, float delta)
 /*  float *a                    lpc coefficients                        */
 /*  int order                   order of LPC coefficients (10)          */
 /*  float *freq                 LSP frequencies in radians              */
 /*  int nb                      number of sub-intervals (4)             */
 /*  float delta                 grid spacing interval (0.02)            */
 {
-    float psuml,psumr,psumm,temp_xr,xl,xr,xm = 0;
-    float temp_psumr;
-    int i,j,m,flag,k;
-    float *px;                  /* ptrs of respective P'(z) & Q'(z)     */
-    float *qx;
-    float *p;
-    float *q;
-    float *pt;                  /* ptr used for cheb_poly_eval()
-                                   whether P' or Q'                     */
-    int roots=0;                /* number of roots found                */
-    float Q[order + 1];
-    float P[order + 1];
-
+  float psuml, psumr, psumm, temp_xr, xl, xr, xm = 0;
+  float temp_psumr;
+  int i, j, m, flag, k;
+  float *px; /* ptrs of respective P'(z) & Q'(z)        */
+  float *qx;
+  float *p;
+  float *q;
+  float *pt;     /* ptr used for cheb_poly_eval()
+                    whether P' or Q'                    */
+  int roots = 0; /* number of roots found               */
+  float Q[order + 1];
+  float P[order + 1];
+
+  flag = 1;
+  m = order / 2; /* order of P'(z) & Q'(z) polynimials  */
+
+  /* Allocate memory space for polynomials */
+
+  /* determine P'(z)'s and Q'(z)'s coefficients where
+    P'(z) = P(z)/(1 + z^(-1)) and Q'(z) = Q(z)/(1-z^(-1)) */
+
+  px = P; /* initilaise ptrs */
+  qx = Q;
+  p = px;
+  q = qx;
+  *px++ = 1.0;
+  *qx++ = 1.0;
+  for (i = 1; i <= m; i++) {
+    *px++ = a[i] + a[order + 1 - i] - *p++;
+    *qx++ = a[i] - a[order + 1 - i] + *q++;
+  }
+  px = P;
+  qx = Q;
+  for (i = 0; i < m; i++) {
+    *px = 2 * *px;
+    *qx = 2 * *qx;
+    px++;
+    qx++;
+  }
+  px = P; /* re-initialise ptrs                         */
+  qx = Q;
+
+  /* Search for a zero in P'(z) polynomial first and then alternate to Q'(z).
+  Keep alternating between the two polynomials as each zero is found    */
+
+  xr = 0;   /* initialise xr to zero            */
+  xl = 1.0; /* start at point xl = 1            */
+
+  for (j = 0; j < order; j++) {
+    if (j % 2) /* determines whether P' or Q' is eval. */
+      pt = qx;
+    else
+      pt = px;
+
+    psuml = cheb_poly_eva(pt, xl, order); /* evals poly. at xl  */
     flag = 1;
-    m = order/2;                /* order of P'(z) & Q'(z) polynimials   */
-
-    /* Allocate memory space for polynomials */
-
-    /* determine P'(z)'s and Q'(z)'s coefficients where
-      P'(z) = P(z)/(1 + z^(-1)) and Q'(z) = Q(z)/(1-z^(-1)) */
-
-    px = P;                      /* initilaise ptrs */
-    qx = Q;
-    p = px;
-    q = qx;
-    *px++ = 1.0;
-    *qx++ = 1.0;
-    for(i=1;i<=m;i++){
-        *px++ = a[i]+a[order+1-i]-*p++;
-        *qx++ = a[i]-a[order+1-i]+*q++;
-    }
-    px = P;
-    qx = Q;
-    for(i=0;i<m;i++){
-        *px = 2**px;
-        *qx = 2**qx;
-         px++;
-         qx++;
-    }
-    px = P;                     /* re-initialise ptrs                   */
-    qx = Q;
-
-    /* Search for a zero in P'(z) polynomial first and then alternate to Q'(z).
-    Keep alternating between the two polynomials as each zero is found  */
-
-    xr = 0;                     /* initialise xr to zero                */
-    xl = 1.0;                   /* start at point xl = 1                */
-
-
-    for(j=0;j<order;j++){
-        if(j%2)                 /* determines whether P' or Q' is eval. */
-            pt = qx;
-        else
-            pt = px;
-
-        psuml = cheb_poly_eva(pt,xl,order);     /* evals poly. at xl    */
-        flag = 1;
-        while(flag && (xr >= -1.0)){
-            xr = xl - delta ;                   /* interval spacing     */
-            psumr = cheb_poly_eva(pt,xr,order);/* poly(xl-delta_x)      */
-            temp_psumr = psumr;
-            temp_xr = xr;
-
-        /* if no sign change increment xr and re-evaluate
-           poly(xr). Repeat til sign change.  if a sign change has
-           occurred the interval is bisected and then checked again
-           for a sign change which determines in which interval the
-           zero lies in.  If there is no sign change between poly(xm)
-           and poly(xl) set interval between xm and xr else set
-           interval between xl and xr and repeat till root is located
-           within the specified limits  */
-
-            if(((psumr*psuml)<0.0) || (psumr == 0.0)){
-                roots++;
-
-                psumm=psuml;
-                for(k=0;k<=nb;k++){
-                    xm = (xl+xr)/2;             /* bisect the interval  */
-                    psumm=cheb_poly_eva(pt,xm,order);
-                    if(psumm*psuml>0.){
-                        psuml=psumm;
-                        xl=xm;
-                    }
-                    else{
-                        psumr=psumm;
-                        xr=xm;
-                    }
-                }
-
-               /* once zero is found, reset initial interval to xr      */
-               freq[j] = (xm);
-               xl = xm;
-               flag = 0;                /* reset flag for next search   */
-            }
-            else{
-                psuml=temp_psumr;
-                xl=temp_xr;
-            }
-        }
+    while (flag && (xr >= -1.0)) {
+      xr = xl - delta;                      /* interval spacing         */
+      psumr = cheb_poly_eva(pt, xr, order); /* poly(xl-delta_x)         */
+      temp_psumr = psumr;
+      temp_xr = xr;
+
+      /* if no sign change increment xr and re-evaluate
+         poly(xr). Repeat til sign change.  if a sign change has
+         occurred the interval is bisected and then checked again
+         for a sign change which determines in which interval the
+         zero lies in.  If there is no sign change between poly(xm)
+         and poly(xl) set interval between xm and xr else set
+         interval between xl and xr and repeat till root is located
+         within the specified limits  */
+
+      if (((psumr * psuml) < 0.0) || (psumr == 0.0)) {
+        roots++;
+
+        psumm = psuml;
+        for (k = 0; k <= nb; k++) {
+          xm = (xl + xr) / 2; /* bisect the interval    */
+          psumm = cheb_poly_eva(pt, xm, order);
+          if (psumm * psuml > 0.) {
+            psuml = psumm;
+            xl = xm;
+          } else {
+            psumr = psumm;
+            xr = xm;
+          }
+        }
+
+        /* once zero is found, reset initial interval to xr     */
+        freq[j] = (xm);
+        xl = xm;
+        flag = 0; /* reset flag for next search         */
+      } else {
+        psuml = temp_psumr;
+        xl = temp_xr;
+      }
     }
+  }
 
-    /* convert from x domain to radians */
+  /* convert from x domain to radians */
 
-    for(i=0; i<order; i++) {
-        freq[i] = acosf(freq[i]);
-    }
+  for (i = 0; i < order; i++) {
+    freq[i] = acosf(freq[i]);
+  }
 
-    return(roots);
+  return (roots);
 }
 
 /*---------------------------------------------------------------------------*\
@@ -263,59 +258,56 @@ void lsp_to_lpc(float *lsp, float *ak, int order)
 /*  float *ak           array of LPC coefficients                       */
 /*  int order           order of LPC coefficients                       */
 
-
 {
-    int i,j;
-    float xout1,xout2,xin1,xin2;
-    float *pw,*n1,*n2,*n3,*n4 = 0;
-    float freq[order];
-    float Wp[(order * 4) + 2];
-
-    /* convert from radians to the x=cos(w) domain */
-
-    for(i=0; i<order; i++)
-        freq[i] = cosf(lsp[i]);
-
-    pw = Wp;
-
-    /* initialise contents of array */
-
-    for(i=0;i<=4*(order/2)+1;i++){              /* set contents of buffer to 0 */
-        *pw++ = 0.0;
-    }
-
-    /* Set pointers up */
-
-    pw = Wp;
-    xin1 = 1.0;
-    xin2 = 1.0;
-
-    /* reconstruct P(z) and Q(z) by cascading second order polynomials
-      in form 1 - 2xz(-1) +z(-2), where x is the LSP coefficient */
-
-    for(j=0;j<=order;j++){
-        for(i=0;i<(order/2);i++){
-            n1 = pw+(i*4);
-            n2 = n1 + 1;
-            n3 = n2 + 1;
-            n4 = n3 + 1;
-            xout1 = xin1 - 2*(freq[2*i]) * *n1 + *n2;
-            xout2 = xin2 - 2*(freq[2*i+1]) * *n3 + *n4;
-            *n2 = *n1;
-            *n4 = *n3;
-            *n1 = xin1;
-            *n3 = xin2;
-            xin1 = xout1;
-            xin2 = xout2;
-        }
-        xout1 = xin1 + *(n4+1);
-        xout2 = xin2 - *(n4+2);
-        ak[j] = (xout1 + xout2)*0.5;
-        *(n4+1) = xin1;
-        *(n4+2) = xin2;
-
-        xin1 = 0.0;
-        xin2 = 0.0;
+  int i, j;
+  float xout1, xout2, xin1, xin2;
+  float *pw, *n1, *n2, *n3, *n4 = 0;
+  float freq[order];
+  float Wp[(order * 4) + 2];
+
+  /* convert from radians to the x=cos(w) domain */
+
+  for (i = 0; i < order; i++) freq[i] = cosf(lsp[i]);
+
+  pw = Wp;
+
+  /* initialise contents of array */
+
+  for (i = 0; i <= 4 * (order / 2) + 1; i++) { /* set contents of buffer to 0 */
+    *pw++ = 0.0;
+  }
+
+  /* Set pointers up */
+
+  pw = Wp;
+  xin1 = 1.0;
+  xin2 = 1.0;
+
+  /* reconstruct P(z) and Q(z) by cascading second order polynomials
+    in form 1 - 2xz(-1) +z(-2), where x is the LSP coefficient */
+
+  for (j = 0; j <= order; j++) {
+    for (i = 0; i < (order / 2); i++) {
+      n1 = pw + (i * 4);
+      n2 = n1 + 1;
+      n3 = n2 + 1;
+      n4 = n3 + 1;
+      xout1 = xin1 - 2 * (freq[2 * i]) * *n1 + *n2;
+      xout2 = xin2 - 2 * (freq[2 * i + 1]) * *n3 + *n4;
+      *n2 = *n1;
+      *n4 = *n3;
+      *n1 = xin1;
+      *n3 = xin2;
+      xin1 = xout1;
+      xin2 = xout2;
     }
+    xout1 = xin1 + *(n4 + 1);
+    xout2 = xin2 - *(n4 + 2);
+    ak[j] = (xout1 + xout2) * 0.5;
+    *(n4 + 1) = xin1;
+    *(n4 + 2) = xin2;
+
+    xin1 = 0.0;
+    xin2 = 0.0;
+  }
 }
-