X-Git-Url: https://scm.cri.ensmp.fr/git/Faustine.git/blobdiff_plain/e775f23a10c4ba37fc1a762299f52cd0d71593b7:/interpretor/libsndfile-1.0.25/src/GSM610/lpc.c..f1f94803668061f90a5ce88bf06ee72bba8e41a5:/interpretor/lib/src/libsndfile-1.0.25/src/GSM610/static/gitweb.js diff --git a/interpretor/libsndfile-1.0.25/src/GSM610/lpc.c b/interpretor/libsndfile-1.0.25/src/GSM610/lpc.c deleted file mode 100644 index 0e776e3..0000000 --- a/interpretor/libsndfile-1.0.25/src/GSM610/lpc.c +++ /dev/null @@ -1,331 +0,0 @@ -/* - * Copyright 1992 by Jutta Degener and Carsten Bormann, Technische - * Universitaet Berlin. See the accompanying file "COPYRIGHT" for - * details. THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE. - */ - -#include -#include - -#include "gsm610_priv.h" - -/* - * 4.2.4 .. 4.2.7 LPC ANALYSIS SECTION - */ - -/* 4.2.4 */ - - -static void Autocorrelation ( - word * s, /* [0..159] IN/OUT */ - longword * L_ACF) /* [0..8] OUT */ -/* - * The goal is to compute the array L_ACF[k]. The signal s[i] must - * be scaled in order to avoid an overflow situation. - */ -{ - register int k, i; - - word temp, smax, scalauto; - -#ifdef USE_FLOAT_MUL - float float_s[160]; -#endif - - /* Dynamic scaling of the array s[0..159] - */ - - /* Search for the maximum. - */ - smax = 0; - for (k = 0; k <= 159; k++) { - temp = GSM_ABS( s[k] ); - if (temp > smax) smax = temp; - } - - /* Computation of the scaling factor. - */ - if (smax == 0) scalauto = 0; - else { - assert(smax > 0); - scalauto = 4 - gsm_norm( (longword)smax << 16 );/* sub(4,..) */ - } - - /* Scaling of the array s[0...159] - */ - - if (scalauto > 0) { - -# ifdef USE_FLOAT_MUL -# define SCALE(n) \ - case n: for (k = 0; k <= 159; k++) \ - float_s[k] = (float) \ - (s[k] = GSM_MULT_R(s[k], 16384 >> (n-1)));\ - break; -# else -# define SCALE(n) \ - case n: for (k = 0; k <= 159; k++) \ - s[k] = GSM_MULT_R( s[k], 16384 >> (n-1) );\ - break; -# endif /* USE_FLOAT_MUL */ - - switch (scalauto) { - SCALE(1) - SCALE(2) - SCALE(3) - SCALE(4) - } -# undef SCALE - } -# ifdef USE_FLOAT_MUL - else for (k = 0; k <= 159; k++) float_s[k] = (float) s[k]; -# endif - - /* Compute the L_ACF[..]. - */ - { -# ifdef USE_FLOAT_MUL - register float * sp = float_s; - register float sl = *sp; - -# define STEP(k) L_ACF[k] += (longword)(sl * sp[ -(k) ]); -# else - word * sp = s; - word sl = *sp; - -# define STEP(k) L_ACF[k] += ((longword)sl * sp[ -(k) ]); -# endif - -# define NEXTI sl = *++sp - - - for (k = 9; k--; L_ACF[k] = 0) ; - - STEP (0); - NEXTI; - STEP(0); STEP(1); - NEXTI; - STEP(0); STEP(1); STEP(2); - NEXTI; - STEP(0); STEP(1); STEP(2); STEP(3); - NEXTI; - STEP(0); STEP(1); STEP(2); STEP(3); STEP(4); - NEXTI; - STEP(0); STEP(1); STEP(2); STEP(3); STEP(4); STEP(5); - NEXTI; - STEP(0); STEP(1); STEP(2); STEP(3); STEP(4); STEP(5); STEP(6); - NEXTI; - STEP(0); STEP(1); STEP(2); STEP(3); STEP(4); STEP(5); STEP(6); STEP(7); - - for (i = 8; i <= 159; i++) { - - NEXTI; - - STEP(0); - STEP(1); STEP(2); STEP(3); STEP(4); - STEP(5); STEP(6); STEP(7); STEP(8); - } - - for (k = 9; k--; L_ACF[k] <<= 1) ; - - } - /* Rescaling of the array s[0..159] - */ - if (scalauto > 0) { - assert(scalauto <= 4); - for (k = 160; k--; *s++ <<= scalauto) ; - } -} - -#if defined(USE_FLOAT_MUL) && defined(FAST) - -static void Fast_Autocorrelation ( - word * s, /* [0..159] IN/OUT */ - longword * L_ACF) /* [0..8] OUT */ -{ - register int k, i; - float f_L_ACF[9]; - float scale; - - float s_f[160]; - register float *sf = s_f; - - for (i = 0; i < 160; ++i) sf[i] = s[i]; - for (k = 0; k <= 8; k++) { - register float L_temp2 = 0; - register float *sfl = sf - k; - for (i = k; i < 160; ++i) L_temp2 += sf[i] * sfl[i]; - f_L_ACF[k] = L_temp2; - } - scale = MAX_LONGWORD / f_L_ACF[0]; - - for (k = 0; k <= 8; k++) { - L_ACF[k] = f_L_ACF[k] * scale; - } -} -#endif /* defined (USE_FLOAT_MUL) && defined (FAST) */ - -/* 4.2.5 */ - -static void Reflection_coefficients ( - longword * L_ACF, /* 0...8 IN */ - register word * r /* 0...7 OUT */ -) -{ - register int i, m, n; - register word temp; - word ACF[9]; /* 0..8 */ - word P[ 9]; /* 0..8 */ - word K[ 9]; /* 2..8 */ - - /* Schur recursion with 16 bits arithmetic. - */ - - if (L_ACF[0] == 0) { - for (i = 8; i--; *r++ = 0) ; - return; - } - - assert( L_ACF[0] != 0 ); - temp = gsm_norm( L_ACF[0] ); - - assert(temp >= 0 && temp < 32); - - /* ? overflow ? */ - for (i = 0; i <= 8; i++) ACF[i] = SASR_L( L_ACF[i] << temp, 16 ); - - /* Initialize array P[..] and K[..] for the recursion. - */ - - for (i = 1; i <= 7; i++) K[ i ] = ACF[ i ]; - for (i = 0; i <= 8; i++) P[ i ] = ACF[ i ]; - - /* Compute reflection coefficients - */ - for (n = 1; n <= 8; n++, r++) { - - temp = P[1]; - temp = GSM_ABS(temp); - if (P[0] < temp) { - for (i = n; i <= 8; i++) *r++ = 0; - return; - } - - *r = gsm_div( temp, P[0] ); - - assert(*r >= 0); - if (P[1] > 0) *r = -*r; /* r[n] = sub(0, r[n]) */ - assert (*r != MIN_WORD); - if (n == 8) return; - - /* Schur recursion - */ - temp = GSM_MULT_R( P[1], *r ); - P[0] = GSM_ADD( P[0], temp ); - - for (m = 1; m <= 8 - n; m++) { - temp = GSM_MULT_R( K[ m ], *r ); - P[m] = GSM_ADD( P[ m+1 ], temp ); - - temp = GSM_MULT_R( P[ m+1 ], *r ); - K[m] = GSM_ADD( K[ m ], temp ); - } - } -} - -/* 4.2.6 */ - -static void Transformation_to_Log_Area_Ratios ( - register word * r /* 0..7 IN/OUT */ -) -/* - * The following scaling for r[..] and LAR[..] has been used: - * - * r[..] = integer( real_r[..]*32768. ); -1 <= real_r < 1. - * LAR[..] = integer( real_LAR[..] * 16384 ); - * with -1.625 <= real_LAR <= 1.625 - */ -{ - register word temp; - register int i; - - - /* Computation of the LAR[0..7] from the r[0..7] - */ - for (i = 1; i <= 8; i++, r++) { - - temp = *r; - temp = GSM_ABS(temp); - assert(temp >= 0); - - if (temp < 22118) { - temp >>= 1; - } else if (temp < 31130) { - assert( temp >= 11059 ); - temp -= 11059; - } else { - assert( temp >= 26112 ); - temp -= 26112; - temp <<= 2; - } - - *r = *r < 0 ? -temp : temp; - assert( *r != MIN_WORD ); - } -} - -/* 4.2.7 */ - -static void Quantization_and_coding ( - register word * LAR /* [0..7] IN/OUT */ -) -{ - register word temp; - - /* This procedure needs four tables; the following equations - * give the optimum scaling for the constants: - * - * A[0..7] = integer( real_A[0..7] * 1024 ) - * B[0..7] = integer( real_B[0..7] * 512 ) - * MAC[0..7] = maximum of the LARc[0..7] - * MIC[0..7] = minimum of the LARc[0..7] - */ - -# undef STEP -# define STEP( A, B, MAC, MIC ) \ - temp = GSM_MULT( A, *LAR ); \ - temp = GSM_ADD( temp, B ); \ - temp = GSM_ADD( temp, 256 ); \ - temp = SASR_W( temp, 9 ); \ - *LAR = temp>MAC ? MAC - MIC : (tempfast) Fast_Autocorrelation (s, L_ACF ); - else -#endif - Autocorrelation (s, L_ACF ); - Reflection_coefficients (L_ACF, LARc ); - Transformation_to_Log_Area_Ratios (LARc); - Quantization_and_coding (LARc); -}