From 4d33f9444a3ed2b2e37cace89e576545523bf431 Mon Sep 17 00:00:00 2001 From: drowe67 Date: Thu, 26 Jun 2014 21:18:13 +0000 Subject: [PATCH] Steve's patch to removed unused variables in LPC routines git-svn-id: https://svn.code.sf.net/p/freetel/code@1712 01035d8c-6547-0410-b346-abe4f91aad63 --- codec2-dev/src/lpc.c | 18 ++++++++---------- 1 file changed, 8 insertions(+), 10 deletions(-) diff --git a/codec2-dev/src/lpc.c b/codec2-dev/src/lpc.c index 66da9a9d..4622dc37 100644 --- a/codec2-dev/src/lpc.c +++ b/codec2-dev/src/lpc.c @@ -156,28 +156,26 @@ void levinson_durbin( int order /* order of the LPC analysis */ ) { - float E[order+1]; - float k[order+1]; float a[order+1][order+1]; - float sum; + float sum, e, k; int i,j; /* loop variables */ - E[0] = R[0]; /* Equation 38a, Makhoul */ + e = R[0]; /* Equation 38a, Makhoul */ for(i=1; i<=order; i++) { sum = 0.0; for(j=1; j<=i-1; j++) sum += a[i-1][j]*R[i-j]; - k[i] = -1.0*(R[i] + sum)/E[i-1]; /* Equation 38b, Makhoul */ - if (fabsf(k[i]) > 1.0) - k[i] = 0.0; + k = -1.0*(R[i] + sum)/e; /* Equation 38b, Makhoul */ + if (fabsf(k) > 1.0) + k = 0.0; - a[i][i] = k[i]; + a[i][i] = k; for(j=1; j<=i-1; j++) - a[i][j] = a[i-1][j] + k[i]*a[i-1][i-j]; /* Equation 38c, Makhoul */ + a[i][j] = a[i-1][j] + k*a[i-1][i-j]; /* Equation 38c, Makhoul */ - E[i] = (1-k[i]*k[i])*E[i-1]; /* Equation 38d, Makhoul */ + e *= (1-k*k); /* Equation 38d, Makhoul */ } for(i=1; i<=order; i++) -- 2.25.1