dec_util.c
上传用户:zhongxx05
上传日期:2007-06-06
资源大小:33641k
文件大小:31k
- /*
- *===================================================================
- * 3GPP AMR Wideband Floating-point Speech Codec
- *===================================================================
- */
- #include "hlxclib/math.h"
- #include "hlxclib/memory.h"
- #include "typedef.h"
- #include "dec_main.h"
- #include "dec_lpc.h"
- #define MAX_16 (Word16)0x7FFF
- #define MIN_16 (Word16)0x8000
- #define L_SUBFR 64 /* Subframe size */
- #define L_SUBFR16k 80 /* Subframe size at 16kHz */
- #define M16k 20 /* Order of LP filter */
- #define PREEMPH_FAC 22282 /* preemphasis factor (0.68 in Q15) */
- #define FAC4 4
- #define FAC5 5
- #define UP_FAC 20480 /* 5/4 in Q14 */
- #define INV_FAC5 6554 /* 1/5 in Q15 */
- #define NB_COEF_UP 12
- #define L_FIR 31
- #define MODE_7k 0
- #define MODE_24k 8
- extern const Word16 D_ROM_pow2[];
- extern const Word16 D_ROM_isqrt[];
- extern const Word16 D_ROM_log2[];
- extern const Word16 D_ROM_fir_up[];
- extern const Word16 D_ROM_fir_6k_7k[];
- extern const Word16 D_ROM_fir_7k[];
- extern const Word16 D_ROM_hp_gain[];
- #ifdef WIN32
- #pragma warning( disable : 4310)
- #endif
- /*
- * D_UTIL_random
- *
- * Parameters:
- * seed I/O: seed for random number
- *
- * Function:
- * Signed 16 bits random generator.
- *
- * Returns:
- * random number
- */
- Word16 D_UTIL_random(Word16 *seed)
- {
- /*static Word16 seed = 21845;*/
- *seed = (Word16)(*seed * 31821L + 13849L);
- return(*seed);
- }
- /*
- * D_UTIL_pow2
- *
- * Parameters:
- * exponant I: (Q0) Integer part. (range: 0 <= val <= 30)
- * fraction I: (Q15) Fractionnal part. (range: 0.0 <= val < 1.0)
- *
- * Function:
- * L_x = pow(2.0, exponant.fraction) (exponant = interger part)
- * = pow(2.0, 0.fraction) << exponant
- *
- * Algorithm:
- *
- * The function Pow2(L_x) is approximated by a table and linear
- * interpolation.
- *
- * 1 - i = bit10 - b15 of fraction, 0 <= i <= 31
- * 2 - a = bit0 - b9 of fraction
- * 3 - L_x = table[i] << 16 - (table[i] - table[i + 1]) * a * 2
- * 4 - L_x = L_x >> (30-exponant) (with rounding)
- *
- * Returns:
- * range 0 <= val <= 0x7fffffff
- */
- Word32 D_UTIL_pow2(Word16 exponant, Word16 fraction)
- {
- Word32 L_x, tmp, i, exp;
- Word16 a;
- L_x = fraction * 32; /* L_x = fraction<<6 */
- i = L_x >> 15; /* Extract b10-b16 of fraction */
- a = (Word16)(L_x); /* Extract b0-b9 of fraction */
- a = (Word16)(a & (Word16)0x7fff);
- L_x = D_ROM_pow2[i] << 16; /* table[i] << 16 */
- tmp = D_ROM_pow2[i] - D_ROM_pow2[i + 1]; /* table[i] - table[i+1] */
- L_x = L_x - ((tmp * a) << 1); /* L_x -= tmp*a*2 */
- exp = 30 - exponant;
- L_x = (L_x + (1 << (exp - 1))) >> exp;
- return(L_x);
- }
- /*
- * D_UTIL_norm_l
- *
- * Parameters:
- * L_var1 I: 32 bit Word32 signed integer (Word32) whose value
- * falls in the range 0x8000 0000 <= var1 <= 0x7fff ffff.
- *
- * Function:
- * Produces the number of left shifts needed to normalize the 32 bit
- * variable L_var1 for positive values on the interval with minimum of
- * 1073741824 and maximum of 2147483647, and for negative values on
- * the interval with minimum of -2147483648 and maximum of -1073741824;
- * in order to normalize the result, the following operation must be done :
- * norm_L_var1 = L_shl(L_var1,norm_l(L_var1)).
- *
- * Returns:
- * 16 bit Word16 signed integer (Word16) whose value falls in the range
- * 0x0000 0000 <= var_out <= 0x0000 001f.
- */
- Word16 D_UTIL_norm_l(Word32 L_var1)
- {
- Word16 var_out;
- if(L_var1 == 0)
- {
- var_out = 0;
- }
- else
- {
- if(L_var1 == (Word32)0xffffffffL)
- {
- var_out = 31;
- }
- else
- {
- if(L_var1 < 0)
- {
- L_var1 = ~L_var1;
- }
- for(var_out = 0; L_var1 < (Word32)0x40000000L; var_out++)
- {
- L_var1 <<= 1;
- }
- }
- }
- return(var_out);
- }
- /*
- * D_UTIL_norm_s
- *
- * Parameters:
- * L_var1 I: 32 bit Word32 signed integer (Word32) whose value
- * falls in the range 0xffff 8000 <= var1 <= 0x0000 7fff.
- *
- * Function:
- * Produces the number of left shift needed to normalize the 16 bit
- * variable var1 for positive values on the interval with minimum
- * of 16384 and maximum of 32767, and for negative values on
- * the interval with minimum of -32768 and maximum of -16384.
- *
- * Returns:
- * 16 bit Word16 signed integer (Word16) whose value falls in the range
- * 0x0000 0000 <= var_out <= 0x0000 000f.
- */
- Word16 D_UTIL_norm_s(Word16 var1)
- {
- Word16 var_out;
- if(var1 == 0)
- {
- var_out = 0;
- }
- else
- {
- if(var1 == -1)
- {
- var_out = 15;
- }
- else
- {
- if(var1 < 0)
- {
- var1 = (Word16)~var1;
- }
- for(var_out = 0; var1 < 0x4000; var_out++)
- {
- var1 <<= 1;
- }
- }
- }
- return(var_out);
- }
- /*
- * D_UTIL_dot_product12
- *
- * Parameters:
- * x I: 12bit x vector
- * y I: 12bit y vector
- * lg I: vector length
- * exp O: exponent of result (0..+30)
- *
- * Function:
- * Compute scalar product of <x[],y[]> using accumulator.
- * The result is normalized (in Q31) with exponent (0..30).
- *
- * Returns:
- * Q31 normalised result (1 < val <= -1)
- */
- Word32 D_UTIL_dot_product12(Word16 x[], Word16 y[], Word16 lg, Word16 *exp)
- {
- Word32 sum, i, sft;
- sum = 0L;
- for(i = 0; i < lg; i++)
- {
- sum += x[i] * y[i];
- }
- sum = (sum << 1) + 1;
- /* Normalize acc in Q31 */
- sft = D_UTIL_norm_l(sum);
- sum = sum << sft;
- *exp = (Word16)(30 - sft); /* exponent = 0..30 */
- return(sum);
- }
- /*
- * D_UTIL_normalised_inverse_sqrt
- *
- * Parameters:
- * frac I/O: (Q31) normalized value (1.0 < frac <= 0.5)
- * exp I/O: exponent (value = frac x 2^exponent)
- *
- * Function:
- * Compute 1/sqrt(value).
- * If value is negative or zero, result is 1 (frac=7fffffff, exp=0).
- *
- * The function 1/sqrt(value) is approximated by a table and linear
- * interpolation.
- * 1. If exponant is odd then shift fraction right once.
- * 2. exponant = -((exponant - 1) >> 1)
- * 3. i = bit25 - b30 of fraction, 16 <= i <= 63 ->because of normalization.
- * 4. a = bit10 - b24
- * 5. i -= 16
- * 6. fraction = table[i]<<16 - (table[i] - table[i+1]) * a * 2
- *
- * Returns:
- * void
- */
- void D_UTIL_normalised_inverse_sqrt(Word32 *frac, Word16 *exp)
- {
- Word32 i, tmp;
- Word16 a;
- if(*frac <= (Word32)0)
- {
- *exp = 0;
- *frac = 0x7fffffffL;
- return;
- }
- if((*exp & 0x1) == 1) /* If exponant odd -> shift right */
- {
- *frac = *frac >> 1;
- }
- *exp = (Word16)(-((*exp - 1) >> 1));
- *frac = *frac >> 9;
- i = *frac >>16; /* Extract b25-b31 */
- *frac = *frac >> 1;
- a = (Word16)(*frac); /* Extract b10-b24 */
- a = (Word16)(a & (Word16)0x7fff);
- i = i - 16;
- *frac = D_ROM_isqrt[i] << 16; /* table[i] << 16 */
- tmp = D_ROM_isqrt[i] - D_ROM_isqrt[i + 1]; /* table[i] - table[i+1]) */
- *frac = *frac - ((tmp * a) << 1); /* frac -= tmp*a*2 */
- return;
- }
- /*
- * D_UTIL_inverse_sqrt
- *
- * Parameters:
- * L_x I/O: (Q0) input value (range: 0<=val<=7fffffff)
- *
- * Function:
- * Compute 1/sqrt(L_x).
- * If value is negative or zero, result is 1 (7fffffff).
- *
- * The function 1/sqrt(value) is approximated by a table and linear
- * interpolation.
- * 1. Normalization of L_x
- * 2. call Normalised_Inverse_sqrt(L_x, exponant)
- * 3. L_y = L_x << exponant
- *
- * Returns:
- * (Q31) output value (range: 0 <= val < 1)
- */
- Word32 D_UTIL_inverse_sqrt(Word32 L_x)
- {
- Word32 L_y;
- Word16 exp;
- exp = D_UTIL_norm_l(L_x);
- L_x = (L_x << exp); /* L_x is normalized */
- exp = (Word16)(31 - exp);
- D_UTIL_normalised_inverse_sqrt(&L_x, &exp);
- if(exp < 0)
- {
- L_y = (L_x >> -exp); /* denormalization */
- }
- else
- {
- L_y = (L_x << exp); /* denormalization */
- }
- return(L_y);
- }
- /*
- * D_UTIL_normalised_log2
- *
- * Parameters:
- * L_x I: input value (normalized)
- * exp I: norm_l (L_x)
- * exponent O: Integer part of Log2. (range: 0<=val<=30)
- * fraction O: Fractional part of Log2. (range: 0<=val<1)
- *
- * Function:
- * Computes log2(L_x, exp), where L_x is positive and
- * normalized, and exp is the normalisation exponent
- * If L_x is negative or zero, the result is 0.
- *
- * The function Log2(L_x) is approximated by a table and linear
- * interpolation. The following steps are used to compute Log2(L_x)
- *
- * 1. exponent = 30 - norm_exponent
- * 2. i = bit25 - b31 of L_x; 32 <= i <= 63 (because of normalization).
- * 3. a = bit10 - b24
- * 4. i -= 32
- * 5. fraction = table[i] << 16 - (table[i] - table[i + 1]) * a * 2
- *
- *
- * Returns:
- * void
- */
- static void D_UTIL_normalised_log2(Word32 L_x, Word16 exp, Word16 *exponent,
- Word16 *fraction)
- {
- Word32 i, a, tmp;
- Word32 L_y;
- if (L_x <= 0)
- {
- *exponent = 0;
- *fraction = 0;
- return;
- }
- *exponent = (Word16)(30 - exp);
- L_x = L_x >> 10;
- i = L_x >> 15; /* Extract b25-b31 */
- a = L_x; /* Extract b10-b24 of fraction */
- a = a & 0x00007fff;
- i = i - 32;
- L_y = D_ROM_log2[i] << 16; /* table[i] << 16 */
- tmp = D_ROM_log2[i] - D_ROM_log2[i + 1]; /* table[i] - table[i+1] */
- L_y = L_y - ((tmp * a) << 1); /* L_y -= tmp*a*2 */
- *fraction = (Word16)(L_y >> 16);
- return;
- }
- /*
- * D_UTIL_log2
- *
- * Parameters:
- * L_x I: input value
- * exponent O: Integer part of Log2. (range: 0<=val<=30)
- * fraction O: Fractional part of Log2. (range: 0<=val<1)
- *
- * Function:
- * Computes log2(L_x), where L_x is positive.
- * If L_x is negative or zero, the result is 0.
- *
- * Returns:
- * void
- */
- void D_UTIL_log2(Word32 L_x, Word16 *exponent, Word16 *fraction)
- {
- Word16 exp;
- exp = D_UTIL_norm_l(L_x);
- D_UTIL_normalised_log2((L_x <<exp), exp, exponent, fraction);
- }
- /*
- * D_UTIL_l_extract
- *
- * Parameters:
- * L_32 I: 32 bit integer.
- * hi O: b16 to b31 of L_32
- * lo O: (L_32 - hi<<16)>>1
- *
- * Function:
- * Extract from a 32 bit integer two 16 bit DPF.
- *
- * Returns:
- * void
- */
- void D_UTIL_l_extract(Word32 L_32, Word16 *hi, Word16 *lo)
- {
- *hi = (Word16)(L_32 >> 16);
- *lo = (Word16)((L_32 >> 1) - (*hi * 32768));
- return;
- }
- /*
- * D_UTIL_mpy_32_16
- *
- * Parameters:
- * hi I: hi part of 32 bit number
- * lo I: lo part of 32 bit number
- * n I: 16 bit number
- *
- * Function:
- * Multiply a 16 bit integer by a 32 bit (DPF). The result is divided
- * by 2^15.
- *
- * L_32 = (hi1*lo2)<<1 + ((lo1*lo2)>>15)<<1
- *
- * Returns:
- * 32 bit result
- */
- Word32 D_UTIL_mpy_32_16(Word16 hi, Word16 lo, Word16 n)
- {
- Word32 L_32;
- L_32 = hi * n;
- L_32 += (lo * n) >> 15;
- return(L_32 << 1);
- }
- /*
- * D_UTIL_mpy_32
- *
- * Parameters:
- * hi1 I: hi part of first number
- * lo1 I: lo part of first number
- * hi2 I: hi part of second number
- * lo2 I: lo part of second number
- *
- * Function:
- * Multiply two 32 bit integers (DPF). The result is divided by 2^31
- *
- * L_32 = (hi1*lo2)<<1 + ((lo1*lo2)>>15)<<1
- *
- * Returns:
- * 32 bit result
- */
- Word32 D_UTIL_mpy_32(Word16 hi1, Word16 lo1, Word16 hi2, Word16 lo2)
- {
- Word32 L_32;
- L_32 = hi1 * hi2;
- L_32 += (hi1 * lo2) >> 15;
- L_32 += (lo1 * hi2) >> 15;
- return(L_32 << 1);
- }
- /*
- * D_UTIL_saturate
- *
- * Parameters:
- * inp I: 32-bit number
- *
- * Function:
- * Saturation to 16-bit number
- *
- * Returns:
- * 16-bit number
- */
- Word16 D_UTIL_saturate(Word32 inp)
- {
- Word16 out;
- if ((inp < MAX_16) & (inp > MIN_16))
- {
- out = (Word16)inp;
- }
- else
- {
- if (inp > 0)
- {
- out = MAX_16;
- }
- else
- {
- out = MIN_16;
- }
- }
- return(out);
- }
- /*
- * D_UTIL_signal_up_scale
- *
- * Parameters:
- * x I/O: signal to scale
- * lg I: size of x[]
- * exp I: exponent: x = round(x << exp)
- *
- * Function:
- * Scale signal up to get maximum of dynamic.
- *
- * Returns:
- * 32 bit result
- */
- void D_UTIL_signal_up_scale(Word16 x[], Word16 lg, Word16 exp)
- {
- Word32 i, tmp;
- for (i = 0; i < lg; i++)
- {
- tmp = x[i] << exp;
- x[i] = D_UTIL_saturate(tmp);
- }
- return;
- }
- /*
- * D_UTIL_signal_down_scale
- *
- * Parameters:
- * x I/O: signal to scale
- * lg I: size of x[]
- * exp I: exponent: x = round(x << exp)
- *
- * Function:
- * Scale signal up to get maximum of dynamic.
- *
- * Returns:
- * 32 bit result
- */
- void D_UTIL_signal_down_scale(Word16 x[], Word16 lg, Word16 exp)
- {
- Word32 i, tmp;
- for(i = 0; i < lg; i++)
- {
- tmp = x[i] << 16;
- tmp = tmp >> exp;
- x[i] = (Word16)((tmp + 0x8000) >> 16);
- }
- return;
- }
- /*
- * D_UTIL_deemph_32
- *
- * Parameters:
- * x_hi I: input signal (bit31..16)
- * x_lo I: input signal (bit15..4)
- * y O: output signal (x16)
- * mu I: (Q15) deemphasis factor
- * L I: vector size
- * mem I/O: memory (y[-1])
- *
- * Function:
- * Filtering through 1/(1-mu z^-1)
- *
- * Returns:
- * void
- */
- static void D_UTIL_deemph_32(Word16 x_hi[], Word16 x_lo[], Word16 y[],
- Word16 mu, Word16 L, Word16 *mem)
- {
- Word32 i, fac;
- Word32 tmp;
- fac = mu >> 1; /* Q15 --> Q14 */
- /* L_tmp = hi<<16 + lo<<4 */
- tmp = (x_hi[0] << 12) + x_lo[0];
- tmp = (tmp << 6) + (*mem * fac);
- tmp = (tmp + 0x2000) >> 14;
- y[0] = D_UTIL_saturate(tmp);
- for(i = 1; i < L; i++)
- {
- tmp = (x_hi[i] << 12) + x_lo[i];
- tmp = (tmp << 6) + (y[i - 1] * fac);
- tmp = (tmp + 0x2000) >> 14;
- y[i] = D_UTIL_saturate(tmp);
- }
- *mem = y[L - 1];
- return;
- }
- /*
- * D_UTIL_synthesis_32
- *
- * Parameters:
- * a I: LP filter coefficients
- * m I: order of LP filter
- * exc I: excitation
- * Qnew I: exc scaling = 0(min) to 8(max)
- * sig_hi O: synthesis high
- * sig_lo O: synthesis low
- * lg I: size of filtering
- *
- * Function:
- * Perform the synthesis filtering 1/A(z).
- *
- * Returns:
- * void
- */
- static void D_UTIL_synthesis_32(Word16 a[], Word16 m, Word16 exc[],
- Word16 Qnew, Word16 sig_hi[], Word16 sig_lo[],
- Word16 lg)
- {
- Word32 i, j, a0;
- Word32 tmp, tmp2;
- a0 = a[0] >> (4 + Qnew); /* input / 16 and >>Qnew */
- /* Do the filtering. */
- for(i = 0; i < lg; i++)
- {
- tmp = 0;
- for(j = 1; j <= m; j++)
- {
- tmp -= sig_lo[i - j] * a[j];
- }
- tmp = tmp >> (15 - 4); /* -4 : sig_lo[i] << 4 */
- tmp2 = exc[i] * a0;
- for(j = 1; j <= m; j++)
- {
- tmp2 -= sig_hi[i - j] * a[j];
- }
- tmp += tmp2 << 1;
- /* sig_hi = bit16 to bit31 of synthesis */
- sig_hi[i] = (Word16)(tmp >> 13);
- /* sig_lo = bit4 to bit15 of synthesis */
- sig_lo[i] = (Word16)((tmp >> 1) - (sig_hi[i] * 4096));
- }
- return;
- }
- /*
- * D_UTIL_hp50_12k8
- *
- * Parameters:
- * signal I/O: signal
- * lg I: lenght of signal
- * mem I/O: filter memory [6]
- *
- * Function:
- * 2nd order high pass filter with cut off frequency at 50 Hz.
- *
- * Algorithm:
- *
- * y[i] = b[0]*x[i] + b[1]*x[i-1] + b[2]*x[i-2]
- * + a[1]*y[i-1] + a[2]*y[i-2];
- *
- * b[3] = {0.989501953f, -1.979003906f, 0.989501953f};
- * a[3] = {1.000000000F, 1.978881836f,-0.966308594f};
- *
- *
- * Returns:
- * void
- */
- static void D_UTIL_hp50_12k8(Word16 signal[], Word16 lg, Word16 mem[])
- {
- Word32 i, L_tmp;
- Word16 y2_hi, y2_lo, y1_hi, y1_lo, x0, x1, x2;
- y2_hi = mem[0];
- y2_lo = mem[1];
- y1_hi = mem[2];
- y1_lo = mem[3];
- x0 = mem[4];
- x1 = mem[5];
- for(i = 0; i < lg; i++)
- {
- x2 = x1;
- x1 = x0;
- x0 = signal[i];
- /* y[i] = b[0]*x[i] + b[1]*x[i-1] + b140[2]*x[i-2] */
- /* + a[1]*y[i-1] + a[2] * y[i-2]; */
- L_tmp = 8192L; /* rounding to maximise precision */
- L_tmp = L_tmp + (y1_lo * 16211);
- L_tmp = L_tmp + (y2_lo * (-8021));
- L_tmp = L_tmp >> 14;
- L_tmp = L_tmp + (y1_hi * 32422);
- L_tmp = L_tmp + (y2_hi * (-16042));
- L_tmp = L_tmp + (x0 * 8106);
- L_tmp = L_tmp + (x1 * (-16212));
- L_tmp = L_tmp + (x2 * 8106);
- L_tmp = L_tmp << 2; /* coeff Q11 --> Q14 */
- y2_hi = y1_hi;
- y2_lo = y1_lo;
- D_UTIL_l_extract(L_tmp, &y1_hi, &y1_lo);
- L_tmp = (L_tmp + 0x4000) >> 15; /* coeff Q14 --> Q15 with saturation */
- signal[i] = D_UTIL_saturate(L_tmp);
- }
- mem[0] = y2_hi;
- mem[1] = y2_lo;
- mem[2] = y1_hi;
- mem[3] = y1_lo;
- mem[4] = x0;
- mem[5] = x1;
- return;
- }
- /*
- * D_UTIL_interpol
- *
- * Parameters:
- * x I: input vector
- * fir I: filter coefficient
- * frac I: fraction (0..resol)
- * up_samp I: resolution
- * nb_coef I: number of coefficients
- *
- * Function:
- * Fractional interpolation of signal at position (frac/up_samp)
- *
- * Returns:
- * result of interpolation
- */
- Word16 D_UTIL_interpol(Word16 *x, Word16 const *fir, Word16 frac,
- Word16 resol, Word16 nb_coef)
- {
- Word32 i, k;
- Word32 sum;
- x = x - nb_coef + 1;
- sum = 0L;
- for(i = 0, k = ((resol - 1) - frac); i < 2 * nb_coef; i++,
- k = (Word16)(k + resol))
- {
- sum = sum + (x[i] * fir[k]);
- }
- if((sum < 536846336) & (sum > -536879104))
- {
- sum = (sum + 0x2000) >> 14;
- }
- else if(sum > 536846336)
- {
- sum = 32767;
- }
- else
- {
- sum = -32768;
- }
- return((Word16)sum); /* saturation can occur here */
- }
- /*
- * D_UTIL_up_samp
- *
- * Parameters:
- * res_d I: signal to upsampling
- * res_u O: upsampled output
- * L_frame I: length of output
- *
- * Function:
- * Upsampling
- *
- * Returns:
- * void
- */
- static void D_UTIL_up_samp(Word16 *sig_d, Word16 *sig_u, Word16 L_frame)
- {
- Word32 pos, i, j;
- Word16 frac;
- pos = 0; /* position with 1/5 resolution */
- for(j = 0; j < L_frame; j++)
- {
- i = (pos * INV_FAC5) >> 15; /* integer part = pos * 1/5 */
- frac = (Word16)(pos - ((i << 2) + i)); /* frac = pos - (pos/5)*5 */
- sig_u[j] = D_UTIL_interpol(&sig_d[i], D_ROM_fir_up, frac, FAC5, NB_COEF_UP);
- pos = pos + FAC4; /* position + 4/5 */
- }
- return;
- }
- /*
- * D_UTIL_oversamp_16k
- *
- * Parameters:
- * sig12k8 I: signal to oversampling
- * lg I: length of input
- * sig16k O: oversampled signal
- * mem I/O: memory (2*12)
- *
- * Function:
- * Oversampling from 12.8kHz to 16kHz
- *
- * Returns:
- * void
- */
- static void D_UTIL_oversamp_16k(Word16 sig12k8[], Word16 lg, Word16 sig16k[],
- Word16 mem[])
- {
- Word16 lg_up;
- Word16 signal[L_SUBFR + (2 * NB_COEF_UP)];
- memcpy(signal, mem, (2 * NB_COEF_UP) * sizeof(Word16));
- memcpy(signal + (2 * NB_COEF_UP), sig12k8, lg * sizeof(Word16));
- lg_up = (Word16)(((lg * UP_FAC) >> 15) << 1);
- D_UTIL_up_samp(signal + NB_COEF_UP, sig16k, lg_up);
- memcpy(mem, signal + lg, (2 * NB_COEF_UP) * sizeof(Word16));
- return;
- }
- /*
- * D_UTIL_hp400_12k8
- *
- * Parameters:
- * signal I/O: signal
- * lg I: lenght of signal
- * mem I/O: filter memory [6]
- *
- * Function:
- * 2nd order high pass filter with cut off frequency at 400 Hz.
- *
- * Algorithm:
- *
- * y[i] = b[0]*x[i] + b[1]*x[i-1] + b[2]*x[i-2]
- * + a[1]*y[i-1] + a[2]*y[i-2];
- *
- * b[3] = {0.893554687, -1.787109375, 0.893554687};
- * a[3] = {1.000000000, 1.787109375, -0.864257812};
- *
- *
- * Returns:
- * void
- */
- void D_UTIL_hp400_12k8(Word16 signal[], Word16 lg, Word16 mem[])
- {
- Word32 i, L_tmp;
- Word16 y2_hi, y2_lo, y1_hi, y1_lo, x0, x1, x2;
- y2_hi = mem[0];
- y2_lo = mem[1];
- y1_hi = mem[2];
- y1_lo = mem[3];
- x0 = mem[4];
- x1 = mem[5];
- for(i = 0; i < lg; i++)
- {
- x2 = x1;
- x1 = x0;
- x0 = signal[i];
- /* y[i] = b[0]*x[i] + b[1]*x[i-1] + b140[2]*x[i-2] */
- /* + a[1]*y[i-1] + a[2] * y[i-2]; */
- L_tmp = 8192L + (y1_lo * 29280);
- L_tmp = L_tmp + (y2_lo * (-14160));
- L_tmp = (L_tmp >> 14);
- L_tmp = L_tmp + (y1_hi * 58560);
- L_tmp = L_tmp + (y2_hi * (-28320));
- L_tmp = L_tmp + (x0 * 1830);
- L_tmp = L_tmp + (x1 * (-3660));
- L_tmp = L_tmp + (x2 * 1830);
- L_tmp = (L_tmp << 1); /* coeff Q12 --> Q13 */
- y2_hi = y1_hi;
- y2_lo = y1_lo;
- D_UTIL_l_extract(L_tmp, &y1_hi, &y1_lo);
- /* signal is divided by 16 to avoid overflow in energy computation */
- signal[i] = (Word16)((L_tmp + 0x8000) >> 16);
- }
- mem[0] = y2_hi;
- mem[1] = y2_lo;
- mem[2] = y1_hi;
- mem[3] = y1_lo;
- mem[4] = x0;
- mem[5] = x1;
- return;
- }
- /*
- * D_UTIL_synthesis
- *
- * Parameters:
- * a I: LP filter coefficients
- * m I: order of LP filter
- * x I: input signal
- * y O: output signal
- * lg I: size of filtering
- * mem I/O: initial filter states
- * update_m I: update memory flag
- *
- * Function:
- * Perform the synthesis filtering 1/A(z).
- *
- * Returns:
- * void
- */
- static void D_UTIL_synthesis(Word16 a[], Word16 m, Word16 x[], Word16 y[],
- Word16 lg, Word16 mem[], Word16 update)
- {
- Word32 i, j, tmp;
- Word16 y_buf[L_SUBFR16k + M16k], a0;
- Word16 *yy;
- yy = &y_buf[m];
- /* copy initial filter states into synthesis buffer */
- memcpy(y_buf, mem, m * sizeof(Word16));
- a0 = (Word16)(a[0] >> 1); /* input / 2 */
- /* Do the filtering. */
- for(i = 0; i < lg; i++)
- {
- tmp = x[i] * a0;
- for(j = 1; j <= m; j++)
- {
- tmp -= a[j] * yy[i - j];
- }
- y[i] = yy[i] = (Word16)((tmp + 0x800) >> 12);
- }
- /* Update memory if required */
- if(update)
- {
- memcpy(mem, &yy[lg - m], m * sizeof(Word16));
- }
- return;
- }
- /*
- * D_UTIL_bp_6k_7k
- *
- * Parameters:
- * signal I/O: signal
- * lg I: lenght of signal
- * mem I/O: filter memory [4]
- *
- * Function:
- * 15th order band pass 6kHz to 7kHz FIR filter.
- *
- * Returns:
- * void
- */
- void D_UTIL_bp_6k_7k(Word16 signal[], Word16 lg, Word16 mem[])
- {
- Word32 x[L_SUBFR16k + (L_FIR - 1)];
- Word32 i, j, tmp;
- for(i = 0; i < (L_FIR - 1); i++)
- {
- x[i] = (Word16)mem[i]; /* gain of filter = 4 */
- }
- for(i = 0; i < lg; i++)
- {
- x[i + L_FIR - 1] = signal[i] >> 2; /* gain of filter = 4 */
- }
- for(i = 0; i < lg; i++)
- {
- tmp = 0;
- for(j = 0; j < L_FIR; j++)
- {
- tmp += x[i + j] * D_ROM_fir_6k_7k[j];
- }
- signal[i] = (Word16)((tmp + 0x4000) >> 15);
- }
- for(i = 0; i < (L_FIR - 1); i++)
- {
- mem[i] = (Word16)x[lg + i]; /* gain of filter = 4 */
- }
- return;
- }
- /*
- * D_UTIL_hp_7k
- *
- * Parameters:
- * signal I/O: ISF vector
- * lg I: length of signal
- * mem I/O: memory (30)
- *
- * Function:
- * 15th order high pass 7kHz FIR filter
- *
- * Returns:
- * void
- */
- static void D_UTIL_hp_7k(Word16 signal[], Word16 lg, Word16 mem[])
- {
- Word32 i, j, tmp;
- Word16 x[L_SUBFR16k + (L_FIR - 1)];
- memcpy(x, mem, (L_FIR - 1) * sizeof(Word16));
- memcpy(&x[L_FIR - 1], signal, lg * sizeof(Word16));
- for(i = 0; i < lg; i++)
- {
- tmp = 0;
- for(j = 0; j < L_FIR; j++)
- {
- tmp += x[i + j] * D_ROM_fir_7k[j];
- }
- signal[i] = (Word16)((tmp + 0x4000) >> 15);
- }
- memcpy(mem, x + lg, (L_FIR - 1) * sizeof(Word16));
- return;
- }
- /*
- * D_UTIL_Dec_synthesis
- *
- * Parameters:
- * Aq I: quantized Az
- * exc I: excitation at 12kHz
- * Q_new I: scaling performed on exc
- * synth16k O: 16kHz synthesis signal
- * prms I: parameters
- * HfIsf I/O: High frequency ISF:s
- * mode I: codec mode
- * newDTXState I: dtx state
- * bfi I: bad frame indicator
- * st I/O: State structure
- *
- * Function:
- * Synthesis of signal at 16kHz with HF extension.
- *
- * Returns:
- * void
- */
- void D_UTIL_dec_synthesis(Word16 Aq[], Word16 exc[], Word16 Q_new,
- Word16 synth16k[], Word16 prms, Word16 HfIsf[],
- Word16 mode, Word16 newDTXState, Word16 bfi,
- Decoder_State *st)
- {
- Word32 tmp, i;
- Word16 exp;
- Word16 ener, exp_ener;
- Word32 fac;
- Word16 synth_hi[M + L_SUBFR], synth_lo[M + L_SUBFR];
- Word16 synth[L_SUBFR];
- Word16 HF[L_SUBFR16k]; /* High Frequency vector */
- Word16 Ap[M16k + 1];
- Word16 HfA[M16k + 1];
- Word16 HF_corr_gain;
- Word16 HF_gain_ind;
- Word32 gain1, gain2;
- Word16 weight1, weight2;
- /*
- * Speech synthesis
- *
- * - Find synthesis speech corresponding to exc2[].
- * - Perform fixed deemphasis and hp 50hz filtering.
- * - Oversampling from 12.8kHz to 16kHz.
- */
- memcpy(synth_hi, st->mem_syn_hi, M * sizeof(Word16));
- memcpy(synth_lo, st->mem_syn_lo, M * sizeof(Word16));
- D_UTIL_synthesis_32(Aq, M, exc, Q_new, synth_hi + M, synth_lo + M, L_SUBFR);
- memcpy(st->mem_syn_hi, synth_hi + L_SUBFR, M * sizeof(Word16));
- memcpy(st->mem_syn_lo, synth_lo + L_SUBFR, M * sizeof(Word16));
- D_UTIL_deemph_32(synth_hi + M, synth_lo + M, synth, PREEMPH_FAC, L_SUBFR,
- &(st->mem_deemph));
- D_UTIL_hp50_12k8(synth, L_SUBFR, st->mem_sig_out);
- D_UTIL_oversamp_16k(synth, L_SUBFR, synth16k, st->mem_oversamp);
- /*
- * HF noise synthesis
- *
- * - Generate HF noise between 5.5 and 7.5 kHz.
- * - Set energy of noise according to synthesis tilt.
- * tilt > 0.8 ==> - 14 dB (voiced)
- * tilt 0.5 ==> - 6 dB (voiced or noise)
- * tilt < 0.0 ==> 0 dB (noise)
- */
- /* generate white noise vector */
- for(i = 0; i < L_SUBFR16k; i++)
- {
- HF[i] = (Word16)(D_UTIL_random(&(st->mem_seed2)) >> 3);
- }
- /* energy of excitation */
- D_UTIL_signal_down_scale(exc, L_SUBFR, 3);
- Q_new = (Word16)(Q_new - 3);
- ener = (Word16)(D_UTIL_dot_product12(exc, exc, L_SUBFR, &exp_ener) >> 16);
- exp_ener = (Word16)(exp_ener - (Q_new << 1));
- /* set energy of white noise to energy of excitation */
- tmp = (Word16)(D_UTIL_dot_product12(HF, HF, L_SUBFR16k, &exp) >> 16);
- if(tmp > ener)
- {
- tmp = tmp >> 1; /* Be sure tmp < ener */
- exp = (Word16)(exp + 1);
- }
- tmp = (tmp << 15) / ener;
- if(tmp > 32767)
- {
- tmp = 32767;
- }
- tmp = tmp << 16; /* result is normalized */
- exp = (Word16)(exp - exp_ener);
- D_UTIL_normalised_inverse_sqrt(&tmp, &exp);
- /* L_tmp x 2, L_tmp in Q31 */
- /* tmp = 2 x sqrt(ener_exc/ener_hf) */
- if(exp >= 0)
- {
- tmp = tmp >> (15 - exp);
- }
- else
- {
- tmp = tmp >> (-exp);
- tmp = tmp >> 15;
- }
- /* saturation */
- if(tmp > 0x7FFF)
- {
- tmp = 0x7FFF;
- }
- for(i = 0; i < L_SUBFR16k; i++)
- {
- HF[i] = (Word16)((HF[i] * tmp) >> 15);
- }
- /* find tilt of synthesis speech (tilt: 1=voiced, -1=unvoiced) */
- D_UTIL_hp400_12k8(synth, L_SUBFR, st->mem_hp400);
- tmp = 0L;
- for(i = 0; i < L_SUBFR; i++)
- {
- tmp = tmp + (synth[i] * synth[i]);
- }
- tmp = (tmp << 1) + 1;
- exp = D_UTIL_norm_l(tmp);
- ener = (Word16)((tmp << exp) >> 16); /* ener = r[0] */
- tmp = 0L;
- for(i = 1; i < L_SUBFR; i++)
- {
- tmp = tmp + (synth[i] * synth[i - 1]);
- }
- tmp = (tmp << 1) + 1;
- tmp = (tmp << exp) >> 16; /* tmp = r[1] */
- if(tmp > 0)
- {
- fac = ((tmp << 15) / ener);
- if(fac > 32767)
- {
- fac = 32767;
- }
- }
- else
- {
- fac = 0;
- }
- /* modify energy of white noise according to synthesis tilt */
- gain1 = (32767 - fac);
- gain2 = ((32767 - fac) * 20480) >> 15;
- gain2 = (gain2 << 1);
- if(gain2 > 32767)
- gain2 = 32767;
- if(st->mem_vad_hist > 0)
- {
- weight1 = 0;
- weight2 = 32767;
- }
- else
- {
- weight1 = 32767;
- weight2 = 0;
- }
- tmp = (weight1 * gain1) >> 15;
- tmp = tmp + ((weight2 * gain2) >> 15);
- if(tmp != 0)
- {
- tmp = tmp + 1;
- }
- if(tmp < 3277)
- {
- tmp = 3277; /* 0.1 in Q15 */
- }
- if((mode == MODE_24k) & (bfi == 0))
- {
- /* HF correction gain */
- HF_gain_ind = prms;
- HF_corr_gain = D_ROM_hp_gain[HF_gain_ind];
- /* HF gain */
- for(i = 0; i < L_SUBFR16k; i++)
- {
- HF[i] = (Word16)(((HF[i] * HF_corr_gain) >> 15) << 1);
- }
- }
- else
- {
- for(i = 0; i < L_SUBFR16k; i++)
- {
- HF[i] = (Word16)((HF[i] * tmp) >> 15);
- }
- }
- if((mode <= MODE_7k) & (newDTXState == SPEECH))
- {
- D_LPC_isf_extrapolation(HfIsf);
- D_LPC_isp_a_conversion(HfIsf, HfA, M16k);
- D_LPC_a_weight(HfA, Ap, 29491, M16k); /* fac=0.9 */
- D_UTIL_synthesis(Ap, M16k, HF, HF, L_SUBFR16k, st->mem_syn_hf, 1);
- }
- else
- {
- /* synthesis of noise: 4.8kHz..5.6kHz --> 6kHz..7kHz */
- D_LPC_a_weight(Aq, Ap, 19661, M); /* fac=0.6 */
- D_UTIL_synthesis(Ap, M, HF, HF, L_SUBFR16k, st->mem_syn_hf + (M16k - M), 1);
- }
- /* noise High Pass filtering (1ms of delay) */
- D_UTIL_bp_6k_7k(HF, L_SUBFR16k, st->mem_hf);
- if(mode == MODE_24k)
- {
- /* Low Pass filtering (7 kHz) */
- D_UTIL_hp_7k(HF, L_SUBFR16k, st->mem_hf3);
- }
- /* add filtered HF noise to speech synthesis */
- for(i = 0; i < L_SUBFR16k; i++)
- {
- tmp = (synth16k[i] + HF[i]);
- synth16k[i] = D_UTIL_saturate(tmp);
- }
- return;
- }
- /*
- * D_UTIL_preemph
- *
- * Parameters:
- * x I/O: signal
- * mu I: preemphasis factor
- * lg I: vector size
- * mem I/O: memory (x[-1])
- *
- * Function:
- * Filtering through 1 - mu z^-1
- *
- *
- * Returns:
- * void
- */
- void D_UTIL_preemph(Word16 x[], Word16 mu, Word16 lg, Word16 *mem)
- {
- Word32 i, L_tmp;
- Word16 temp;
- temp = x[lg - 1];
- for(i = lg - 1; i > 0; i--)
- {
- L_tmp = x[i] << 15;
- L_tmp = L_tmp - (x[i - 1] * mu);
- x[i] = (Word16)((L_tmp + 0x4000) >> 15);
- }
- L_tmp = x[0] << 15;
- L_tmp = L_tmp - (*mem * mu);
- x[0] = (Word16)((L_tmp + 0x4000) >> 15);
- *mem = temp;
- return;
- }