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-rw-r--r--1.2-netsec/codecs/ilbc/lsf.c264
1 files changed, 0 insertions, 264 deletions
diff --git a/1.2-netsec/codecs/ilbc/lsf.c b/1.2-netsec/codecs/ilbc/lsf.c
deleted file mode 100644
index 055c21cb5..000000000
--- a/1.2-netsec/codecs/ilbc/lsf.c
+++ /dev/null
@@ -1,264 +0,0 @@
-
-/******************************************************************
-
- iLBC Speech Coder ANSI-C Source Code
-
- lsf.c
-
- Copyright (C) The Internet Society (2004).
- All Rights Reserved.
-
-******************************************************************/
-
-#include <string.h>
-#include <math.h>
-
-#include "iLBC_define.h"
-#include "lsf.h"
-
-/*----------------------------------------------------------------*
- * conversion from lpc coefficients to lsf coefficients
- *---------------------------------------------------------------*/
-
-void a2lsf(
- float *freq,/* (o) lsf coefficients */
- float *a /* (i) lpc coefficients */
-){
- float steps[LSF_NUMBER_OF_STEPS] =
- {(float)0.00635, (float)0.003175, (float)0.0015875,
- (float)0.00079375};
- float step;
- int step_idx;
- int lsp_index;
- float p[LPC_HALFORDER];
- float q[LPC_HALFORDER];
- float p_pre[LPC_HALFORDER];
-
-
- float q_pre[LPC_HALFORDER];
- float old_p, old_q, *old;
- float *pq_coef;
- float omega, old_omega;
- int i;
- float hlp, hlp1, hlp2, hlp3, hlp4, hlp5;
-
- for (i=0; i<LPC_HALFORDER; i++) {
- p[i] = (float)-1.0 * (a[i + 1] + a[LPC_FILTERORDER - i]);
- q[i] = a[LPC_FILTERORDER - i] - a[i + 1];
- }
-
- p_pre[0] = (float)-1.0 - p[0];
- p_pre[1] = - p_pre[0] - p[1];
- p_pre[2] = - p_pre[1] - p[2];
- p_pre[3] = - p_pre[2] - p[3];
- p_pre[4] = - p_pre[3] - p[4];
- p_pre[4] = p_pre[4] / 2;
-
- q_pre[0] = (float)1.0 - q[0];
- q_pre[1] = q_pre[0] - q[1];
- q_pre[2] = q_pre[1] - q[2];
- q_pre[3] = q_pre[2] - q[3];
- q_pre[4] = q_pre[3] - q[4];
- q_pre[4] = q_pre[4] / 2;
-
- omega = 0.0;
- old_omega = 0.0;
-
- old_p = FLOAT_MAX;
- old_q = FLOAT_MAX;
-
- /* Here we loop through lsp_index to find all the
- LPC_FILTERORDER roots for omega. */
-
- for (lsp_index = 0; lsp_index<LPC_FILTERORDER; lsp_index++) {
-
- /* Depending on lsp_index being even or odd, we
- alternatively solve the roots for the two LSP equations. */
-
-
- if ((lsp_index & 0x1) == 0) {
- pq_coef = p_pre;
- old = &old_p;
- } else {
- pq_coef = q_pre;
- old = &old_q;
- }
-
- /* Start with low resolution grid */
-
- for (step_idx = 0, step = steps[step_idx];
- step_idx < LSF_NUMBER_OF_STEPS;){
-
-
-
- /* cos(10piw) + pq(0)cos(8piw) + pq(1)cos(6piw) +
- pq(2)cos(4piw) + pq(3)cod(2piw) + pq(4) */
-
- hlp = (float)cos(omega * TWO_PI);
- hlp1 = (float)2.0 * hlp + pq_coef[0];
- hlp2 = (float)2.0 * hlp * hlp1 - (float)1.0 +
- pq_coef[1];
- hlp3 = (float)2.0 * hlp * hlp2 - hlp1 + pq_coef[2];
- hlp4 = (float)2.0 * hlp * hlp3 - hlp2 + pq_coef[3];
- hlp5 = hlp * hlp4 - hlp3 + pq_coef[4];
-
-
- if (((hlp5 * (*old)) <= 0.0) || (omega >= 0.5)){
-
- if (step_idx == (LSF_NUMBER_OF_STEPS - 1)){
-
- if (fabs(hlp5) >= fabs(*old)) {
- freq[lsp_index] = omega - step;
- } else {
- freq[lsp_index] = omega;
- }
-
-
- if ((*old) >= 0.0){
- *old = (float)-1.0 * FLOAT_MAX;
- } else {
- *old = FLOAT_MAX;
- }
-
- omega = old_omega;
- step_idx = 0;
-
- step_idx = LSF_NUMBER_OF_STEPS;
- } else {
-
- if (step_idx == 0) {
- old_omega = omega;
- }
-
- step_idx++;
- omega -= steps[step_idx];
-
- /* Go back one grid step */
-
- step = steps[step_idx];
- }
- } else {
-
- /* increment omega until they are of different sign,
- and we know there is at least one root between omega
- and old_omega */
- *old = hlp5;
- omega += step;
- }
-
-
- }
- }
-
- for (i = 0; i<LPC_FILTERORDER; i++) {
- freq[i] = freq[i] * TWO_PI;
- }
-}
-
-/*----------------------------------------------------------------*
- * conversion from lsf coefficients to lpc coefficients
- *---------------------------------------------------------------*/
-
-void lsf2a(
- float *a_coef, /* (o) lpc coefficients */
- float *freq /* (i) lsf coefficients */
-){
- int i, j;
- float hlp;
- float p[LPC_HALFORDER], q[LPC_HALFORDER];
- float a[LPC_HALFORDER + 1], a1[LPC_HALFORDER],
- a2[LPC_HALFORDER];
- float b[LPC_HALFORDER + 1], b1[LPC_HALFORDER],
- b2[LPC_HALFORDER];
-
- for (i=0; i<LPC_FILTERORDER; i++) {
- freq[i] = freq[i] * PI2;
- }
-
- /* Check input for ill-conditioned cases. This part is not
- found in the TIA standard. It involves the following 2 IF
- blocks. If "freq" is judged ill-conditioned, then we first
- modify freq[0] and freq[LPC_HALFORDER-1] (normally
- LPC_HALFORDER = 10 for LPC applications), then we adjust
- the other "freq" values slightly */
-
-
- if ((freq[0] <= 0.0) || (freq[LPC_FILTERORDER - 1] >= 0.5)){
-
-
- if (freq[0] <= 0.0) {
- freq[0] = (float)0.022;
- }
-
-
- if (freq[LPC_FILTERORDER - 1] >= 0.5) {
- freq[LPC_FILTERORDER - 1] = (float)0.499;
- }
-
- hlp = (freq[LPC_FILTERORDER - 1] - freq[0]) /
- (float) (LPC_FILTERORDER - 1);
-
- for (i=1; i<LPC_FILTERORDER; i++) {
- freq[i] = freq[i - 1] + hlp;
- }
-
-
- }
-
- memset(a1, 0, LPC_HALFORDER*sizeof(float));
- memset(a2, 0, LPC_HALFORDER*sizeof(float));
- memset(b1, 0, LPC_HALFORDER*sizeof(float));
- memset(b2, 0, LPC_HALFORDER*sizeof(float));
- memset(a, 0, (LPC_HALFORDER+1)*sizeof(float));
- memset(b, 0, (LPC_HALFORDER+1)*sizeof(float));
-
- /* p[i] and q[i] compute cos(2*pi*omega_{2j}) and
- cos(2*pi*omega_{2j-1} in eqs. 4.2.2.2-1 and 4.2.2.2-2.
- Note that for this code p[i] specifies the coefficients
- used in .Q_A(z) while q[i] specifies the coefficients used
- in .P_A(z) */
-
- for (i=0; i<LPC_HALFORDER; i++) {
- p[i] = (float)cos(TWO_PI * freq[2 * i]);
- q[i] = (float)cos(TWO_PI * freq[2 * i + 1]);
- }
-
- a[0] = 0.25;
- b[0] = 0.25;
-
- for (i= 0; i<LPC_HALFORDER; i++) {
- a[i + 1] = a[i] - 2 * p[i] * a1[i] + a2[i];
- b[i + 1] = b[i] - 2 * q[i] * b1[i] + b2[i];
- a2[i] = a1[i];
- a1[i] = a[i];
- b2[i] = b1[i];
- b1[i] = b[i];
- }
-
- for (j=0; j<LPC_FILTERORDER; j++) {
-
- if (j == 0) {
- a[0] = 0.25;
- b[0] = -0.25;
- } else {
- a[0] = b[0] = 0.0;
- }
-
- for (i=0; i<LPC_HALFORDER; i++) {
- a[i + 1] = a[i] - 2 * p[i] * a1[i] + a2[i];
- b[i + 1] = b[i] - 2 * q[i] * b1[i] + b2[i];
- a2[i] = a1[i];
- a1[i] = a[i];
- b2[i] = b1[i];
- b1[i] = b[i];
- }
-
- a_coef[j + 1] = 2 * (a[LPC_HALFORDER] + b[LPC_HALFORDER]);
- }
-
- a_coef[0] = 1.0;
-
-
-}
-
-
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