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Diffstat (limited to 'media/libstagefright/codecs/amrwbenc/src/pitch_f4.c')
-rw-r--r-- | media/libstagefright/codecs/amrwbenc/src/pitch_f4.c | 324 |
1 files changed, 324 insertions, 0 deletions
diff --git a/media/libstagefright/codecs/amrwbenc/src/pitch_f4.c b/media/libstagefright/codecs/amrwbenc/src/pitch_f4.c new file mode 100644 index 0000000..0d66c31 --- /dev/null +++ b/media/libstagefright/codecs/amrwbenc/src/pitch_f4.c @@ -0,0 +1,324 @@ +/* + ** Copyright 2003-2010, VisualOn, Inc. + ** + ** Licensed under the Apache License, Version 2.0 (the "License"); + ** you may not use this file except in compliance with the License. + ** You may obtain a copy of the License at + ** + ** http://www.apache.org/licenses/LICENSE-2.0 + ** + ** Unless required by applicable law or agreed to in writing, software + ** distributed under the License is distributed on an "AS IS" BASIS, + ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + ** See the License for the specific language governing permissions and + ** limitations under the License. + */ + +/*********************************************************************** +* File: pitch_f4.c * +* * +* Description: Find the closed loop pitch period with * +* 1/4 subsample resolution. * +* * +************************************************************************/ + +#include "typedef.h" +#include "basic_op.h" +#include "math_op.h" +#include "acelp.h" +#include "cnst.h" + +#define UP_SAMP 4 +#define L_INTERPOL1 4 + +/* Local functions */ + +#ifdef ASM_OPT +void Norm_corr_asm( + Word16 exc[], /* (i) : excitation buffer */ + Word16 xn[], /* (i) : target vector */ + Word16 h[], /* (i) Q15 : impulse response of synth/wgt filters */ + Word16 L_subfr, + Word16 t_min, /* (i) : minimum value of pitch lag. */ + Word16 t_max, /* (i) : maximum value of pitch lag. */ + Word16 corr_norm[] /* (o) Q15 : normalized correlation */ + ); +#else +static void Norm_Corr( + Word16 exc[], /* (i) : excitation buffer */ + Word16 xn[], /* (i) : target vector */ + Word16 h[], /* (i) Q15 : impulse response of synth/wgt filters */ + Word16 L_subfr, + Word16 t_min, /* (i) : minimum value of pitch lag. */ + Word16 t_max, /* (i) : maximum value of pitch lag. */ + Word16 corr_norm[] /* (o) Q15 : normalized correlation */ + ); +#endif + +static Word16 Interpol_4( /* (o) : interpolated value */ + Word16 * x, /* (i) : input vector */ + Word32 frac /* (i) : fraction (-4..+3) */ + ); + + +Word16 Pitch_fr4( /* (o) : pitch period. */ + Word16 exc[], /* (i) : excitation buffer */ + Word16 xn[], /* (i) : target vector */ + Word16 h[], /* (i) Q15 : impulse response of synth/wgt filters */ + Word16 t0_min, /* (i) : minimum value in the searched range. */ + Word16 t0_max, /* (i) : maximum value in the searched range. */ + Word16 * pit_frac, /* (o) : chosen fraction (0, 1, 2 or 3). */ + Word16 i_subfr, /* (i) : indicator for first subframe. */ + Word16 t0_fr2, /* (i) : minimum value for resolution 1/2 */ + Word16 t0_fr1, /* (i) : minimum value for resolution 1 */ + Word16 L_subfr /* (i) : Length of subframe */ + ) +{ + Word32 fraction, i; + Word16 t_min, t_max; + Word16 max, t0, step, temp; + Word16 *corr; + Word16 corr_v[40]; /* Total length = t0_max-t0_min+1+2*L_inter */ + + /* Find interval to compute normalized correlation */ + + t_min = t0_min - L_INTERPOL1; + t_max = t0_max + L_INTERPOL1; + corr = &corr_v[-t_min]; + /* Compute normalized correlation between target and filtered excitation */ +#ifdef ASM_OPT /* asm optimization branch */ + Norm_corr_asm(exc, xn, h, L_subfr, t_min, t_max, corr); +#else + Norm_Corr(exc, xn, h, L_subfr, t_min, t_max, corr); +#endif + + /* Find integer pitch */ + + max = corr[t0_min]; + t0 = t0_min; + for (i = t0_min + 1; i <= t0_max; i++) + { + if (corr[i] >= max) + { + max = corr[i]; + t0 = i; + } + } + /* If first subframe and t0 >= t0_fr1, do not search fractionnal pitch */ + if ((i_subfr == 0) && (t0 >= t0_fr1)) + { + *pit_frac = 0; + return (t0); + } + /*------------------------------------------------------------------* + * Search fractionnal pitch with 1/4 subsample resolution. * + * Test the fractions around t0 and choose the one which maximizes * + * the interpolated normalized correlation. * + *------------------------------------------------------------------*/ + + step = 1; /* 1/4 subsample resolution */ + fraction = -3; + if ((t0_fr2 == PIT_MIN)||((i_subfr == 0) && (t0 >= t0_fr2))) + { + step = 2; /* 1/2 subsample resolution */ + fraction = -2; + } + if(t0 == t0_min) + { + fraction = 0; + } + max = Interpol_4(&corr[t0], fraction); + + for (i = fraction + step; i <= 3; i += step) + { + temp = Interpol_4(&corr[t0], i); + if(temp > max) + { + max = temp; + fraction = i; + } + } + /* limit the fraction value in the interval [0,1,2,3] */ + if (fraction < 0) + { + fraction += UP_SAMP; + t0 -= 1; + } + *pit_frac = fraction; + return (t0); +} + + +/*********************************************************************************** +* Function: Norm_Corr() * +* * +* Description: Find the normalized correlation between the target vector and the * +* filtered past excitation. * +* (correlation between target and filtered excitation divided by the * +* square root of energy of target and filtered excitation). * +************************************************************************************/ +#ifndef ASM_OPT +static void Norm_Corr( + Word16 exc[], /* (i) : excitation buffer */ + Word16 xn[], /* (i) : target vector */ + Word16 h[], /* (i) Q15 : impulse response of synth/wgt filters */ + Word16 L_subfr, + Word16 t_min, /* (i) : minimum value of pitch lag. */ + Word16 t_max, /* (i) : maximum value of pitch lag. */ + Word16 corr_norm[]) /* (o) Q15 : normalized correlation */ +{ + Word32 i, k, t; + Word32 corr, exp_corr, norm, exp, scale; + Word16 exp_norm, excf[L_SUBFR], tmp; + Word32 L_tmp, L_tmp1, L_tmp2; + + /* compute the filtered excitation for the first delay t_min */ + k = -t_min; + +#ifdef ASM_OPT /* asm optimization branch */ + Convolve_asm(&exc[k], h, excf, 64); +#else + Convolve(&exc[k], h, excf, 64); +#endif + + /* Compute rounded down 1/sqrt(energy of xn[]) */ + L_tmp = 0; + for (i = 0; i < 64; i+=4) + { + L_tmp += (xn[i] * xn[i]); + L_tmp += (xn[i+1] * xn[i+1]); + L_tmp += (xn[i+2] * xn[i+2]); + L_tmp += (xn[i+3] * xn[i+3]); + } + + L_tmp = (L_tmp << 1) + 1; + exp = norm_l(L_tmp); + exp = (32 - exp); + //exp = exp + 2; /* energy of xn[] x 2 + rounded up */ + scale = -(exp >> 1); /* (1<<scale) < 1/sqrt(energy rounded) */ + + /* loop for every possible period */ + + for (t = t_min; t <= t_max; t++) + { + /* Compute correlation between xn[] and excf[] */ + L_tmp = 0; + L_tmp1 = 0; + for (i = 0; i < 64; i+=4) + { + L_tmp += (xn[i] * excf[i]); + L_tmp1 += (excf[i] * excf[i]); + L_tmp += (xn[i+1] * excf[i+1]); + L_tmp1 += (excf[i+1] * excf[i+1]); + L_tmp += (xn[i+2] * excf[i+2]); + L_tmp1 += (excf[i+2] * excf[i+2]); + L_tmp += (xn[i+3] * excf[i+3]); + L_tmp1 += (excf[i+3] * excf[i+3]); + } + + L_tmp = (L_tmp << 1) + 1; + L_tmp1 = (L_tmp1 << 1) + 1; + + exp = norm_l(L_tmp); + L_tmp = (L_tmp << exp); + exp_corr = (30 - exp); + corr = extract_h(L_tmp); + + exp = norm_l(L_tmp1); + L_tmp = (L_tmp1 << exp); + exp_norm = (30 - exp); + + Isqrt_n(&L_tmp, &exp_norm); + norm = extract_h(L_tmp); + + /* Normalize correlation = correlation * (1/sqrt(energy)) */ + + L_tmp = vo_L_mult(corr, norm); + + L_tmp2 = exp_corr + exp_norm + scale; + if(L_tmp2 < 0) + { + L_tmp2 = -L_tmp2; + L_tmp = L_tmp >> L_tmp2; + } + else + { + L_tmp = L_tmp << L_tmp2; + } + + corr_norm[t] = vo_round(L_tmp); + /* modify the filtered excitation excf[] for the next iteration */ + + if(t != t_max) + { + k = -(t + 1); + tmp = exc[k]; + for (i = 63; i > 0; i--) + { + excf[i] = add1(vo_mult(tmp, h[i]), excf[i - 1]); + } + excf[0] = vo_mult(tmp, h[0]); + } + } + return; +} + +#endif +/************************************************************************************ +* Function: Interpol_4() * +* * +* Description: For interpolating the normalized correlation with 1/4 resolution. * +**************************************************************************************/ + +/* 1/4 resolution interpolation filter (-3 dB at 0.791*fs/2) in Q14 */ +static Word16 inter4_1[4][8] = +{ + {-12, 420, -1732, 5429, 13418, -1242, 73, 32}, + {-26, 455, -2142, 9910, 9910, -2142, 455, -26}, + {32, 73, -1242, 13418, 5429, -1732, 420, -12}, + {206, -766, 1376, 14746, 1376, -766, 206, 0} +}; + +/*** Coefficients in floating point +static float inter4_1[UP_SAMP*L_INTERPOL1+1] = { +0.900000, +0.818959, 0.604850, 0.331379, 0.083958, +-0.075795, -0.130717, -0.105685, -0.046774, +0.004467, 0.027789, 0.025642, 0.012571, +0.001927, -0.001571, -0.000753, 0.000000}; +***/ + +static Word16 Interpol_4( /* (o) : interpolated value */ + Word16 * x, /* (i) : input vector */ + Word32 frac /* (i) : fraction (-4..+3) */ + ) +{ + Word16 sum; + Word32 k, L_sum; + Word16 *ptr; + + if (frac < 0) + { + frac += UP_SAMP; + x--; + } + x = x - L_INTERPOL1 + 1; + k = UP_SAMP - 1 - frac; + ptr = &(inter4_1[k][0]); + + L_sum = vo_mult32(x[0], (*ptr++)); + L_sum += vo_mult32(x[1], (*ptr++)); + L_sum += vo_mult32(x[2], (*ptr++)); + L_sum += vo_mult32(x[3], (*ptr++)); + L_sum += vo_mult32(x[4], (*ptr++)); + L_sum += vo_mult32(x[5], (*ptr++)); + L_sum += vo_mult32(x[6], (*ptr++)); + L_sum += vo_mult32(x[7], (*ptr++)); + + sum = extract_h(L_add(L_shl2(L_sum, 2), 0x8000)); + return (sum); +} + + + + |