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Make the LSP naming more consistent

Use the convention from lsp.c: an LSF is a frequency, an LSP is the
cosine of an LSF, and LSP functions should have an ff_acelp prefix.
Use a "d" suffix to specify doubles.

Patch by Colin McQuillan ( m.niloc googlemail com )

Originally committed as revision 19570 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Colin McQuillan 2009-08-03 08:31:20 +00:00 committed by Robert Swain
parent b5fe06abf0
commit 1e1e02eacd
2 changed files with 13 additions and 13 deletions

View File

@ -34,21 +34,21 @@
* needed for LSP to LPC conversion.
* We only need to calculate the 6 first elements of the polynomial.
*
* @param lspf line spectral pair frequencies
* @param lsp line spectral pairs in cosine domain
* @param f [out] polynomial input/output as a vector
*
* TIA/EIA/IS-733 2.4.3.3.5-1/2
*/
static void lsp2polyf(const double *lspf, double *f, int lp_half_order)
static void lsp2polyf(const double *lsp, double *f, int lp_half_order)
{
int i, j;
f[0] = 1.0;
f[1] = -2 * lspf[0];
lspf -= 2;
f[1] = -2 * lsp[0];
lsp -= 2;
for(i=2; i<=lp_half_order; i++)
{
double val = -2 * lspf[2*i];
double val = -2 * lsp[2*i];
f[i] = val * f[i-1] + 2*f[i-2];
for(j=i-1; j>1; j--)
f[j] += f[j-1] * val + f[j-2];
@ -59,16 +59,16 @@ static void lsp2polyf(const double *lspf, double *f, int lp_half_order)
/**
* Reconstructs LPC coefficients from the line spectral pair frequencies.
*
* @param lspf line spectral pair frequencies
* @param lsp line spectral pairs in cosine domain
* @param lpc linear predictive coding coefficients
*/
void ff_celp_lspf2lpc(const double *lspf, float *lpc)
void ff_acelp_lspd2lpc(const double *lsp, float *lpc)
{
double pa[6], qa[6];
int i;
lsp2polyf(lspf, pa, 5);
lsp2polyf(lspf + 1, qa, 5);
lsp2polyf(lsp, pa, 5);
lsp2polyf(lsp + 1, qa, 5);
for (i=4; i>=0; i--)
{

View File

@ -80,7 +80,7 @@ typedef struct
*
* TIA/EIA/IS-733 2.4.3.3.5
*/
void ff_celp_lspf2lpc(const double *lspf, float *lpc);
void ff_acelp_lspd2lpc(const double *lsp, float *lpc);
/**
* Initialize the speech codec according to the specification.
@ -604,14 +604,14 @@ static void apply_pitch_filters(QCELPContext *q, float *cdn_vector)
*/
static void lspf2lpc(const float *lspf, float *lpc)
{
double lsf[10];
double lsp[10];
double bandwidth_expansion_coeff = QCELP_BANDWIDTH_EXPANSION_COEFF;
int i;
for (i=0; i<10; i++)
lsf[i] = cos(M_PI * lspf[i]);
lsp[i] = cos(M_PI * lspf[i]);
ff_celp_lspf2lpc(lsf, lpc);
ff_acelp_lspd2lpc(lsp, lpc);
for (i=0; i<10; i++)
{