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Diffstat (limited to 'media/libopus/celt/celt_lpc.c')
-rw-r--r-- | media/libopus/celt/celt_lpc.c | 314 |
1 files changed, 314 insertions, 0 deletions
diff --git a/media/libopus/celt/celt_lpc.c b/media/libopus/celt/celt_lpc.c new file mode 100644 index 000000000..b410a21c5 --- /dev/null +++ b/media/libopus/celt/celt_lpc.c @@ -0,0 +1,314 @@ +/* Copyright (c) 2009-2010 Xiph.Org Foundation + Written by Jean-Marc Valin */ +/* + Redistribution and use in source and binary forms, with or without + modification, are permitted provided that the following conditions + are met: + + - Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. + + - Redistributions in binary form must reproduce the above copyright + notice, this list of conditions and the following disclaimer in the + documentation and/or other materials provided with the distribution. + + THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER + OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, + EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, + PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR + PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF + LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING + NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS + SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +*/ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#include "celt_lpc.h" +#include "stack_alloc.h" +#include "mathops.h" +#include "pitch.h" + +void _celt_lpc( + opus_val16 *_lpc, /* out: [0...p-1] LPC coefficients */ +const opus_val32 *ac, /* in: [0...p] autocorrelation values */ +int p +) +{ + int i, j; + opus_val32 r; + opus_val32 error = ac[0]; +#ifdef FIXED_POINT + opus_val32 lpc[LPC_ORDER]; +#else + float *lpc = _lpc; +#endif + + OPUS_CLEAR(lpc, p); + if (ac[0] != 0) + { + for (i = 0; i < p; i++) { + /* Sum up this iteration's reflection coefficient */ + opus_val32 rr = 0; + for (j = 0; j < i; j++) + rr += MULT32_32_Q31(lpc[j],ac[i - j]); + rr += SHR32(ac[i + 1],3); + r = -frac_div32(SHL32(rr,3), error); + /* Update LPC coefficients and total error */ + lpc[i] = SHR32(r,3); + for (j = 0; j < (i+1)>>1; j++) + { + opus_val32 tmp1, tmp2; + tmp1 = lpc[j]; + tmp2 = lpc[i-1-j]; + lpc[j] = tmp1 + MULT32_32_Q31(r,tmp2); + lpc[i-1-j] = tmp2 + MULT32_32_Q31(r,tmp1); + } + + error = error - MULT32_32_Q31(MULT32_32_Q31(r,r),error); + /* Bail out once we get 30 dB gain */ +#ifdef FIXED_POINT + if (error<SHR32(ac[0],10)) + break; +#else + if (error<.001f*ac[0]) + break; +#endif + } + } +#ifdef FIXED_POINT + for (i=0;i<p;i++) + _lpc[i] = ROUND16(lpc[i],16); +#endif +} + + +void celt_fir_c( + const opus_val16 *_x, + const opus_val16 *num, + opus_val16 *_y, + int N, + int ord, + opus_val16 *mem, + int arch) +{ + int i,j; + VARDECL(opus_val16, rnum); + VARDECL(opus_val16, x); + SAVE_STACK; + + ALLOC(rnum, ord, opus_val16); + ALLOC(x, N+ord, opus_val16); + for(i=0;i<ord;i++) + rnum[i] = num[ord-i-1]; + for(i=0;i<ord;i++) + x[i] = mem[ord-i-1]; + for (i=0;i<N;i++) + x[i+ord]=_x[i]; + for(i=0;i<ord;i++) + mem[i] = _x[N-i-1]; +#ifdef SMALL_FOOTPRINT + (void)arch; + for (i=0;i<N;i++) + { + opus_val32 sum = SHL32(EXTEND32(_x[i]), SIG_SHIFT); + for (j=0;j<ord;j++) + { + sum = MAC16_16(sum,rnum[j],x[i+j]); + } + _y[i] = SATURATE16(PSHR32(sum, SIG_SHIFT)); + } +#else + for (i=0;i<N-3;i+=4) + { + opus_val32 sum[4]={0,0,0,0}; + xcorr_kernel(rnum, x+i, sum, ord, arch); + _y[i ] = SATURATE16(ADD32(EXTEND32(_x[i ]), PSHR32(sum[0], SIG_SHIFT))); + _y[i+1] = SATURATE16(ADD32(EXTEND32(_x[i+1]), PSHR32(sum[1], SIG_SHIFT))); + _y[i+2] = SATURATE16(ADD32(EXTEND32(_x[i+2]), PSHR32(sum[2], SIG_SHIFT))); + _y[i+3] = SATURATE16(ADD32(EXTEND32(_x[i+3]), PSHR32(sum[3], SIG_SHIFT))); + } + for (;i<N;i++) + { + opus_val32 sum = 0; + for (j=0;j<ord;j++) + sum = MAC16_16(sum,rnum[j],x[i+j]); + _y[i] = SATURATE16(ADD32(EXTEND32(_x[i]), PSHR32(sum, SIG_SHIFT))); + } +#endif + RESTORE_STACK; +} + +void celt_iir(const opus_val32 *_x, + const opus_val16 *den, + opus_val32 *_y, + int N, + int ord, + opus_val16 *mem, + int arch) +{ +#ifdef SMALL_FOOTPRINT + int i,j; + (void)arch; + for (i=0;i<N;i++) + { + opus_val32 sum = _x[i]; + for (j=0;j<ord;j++) + { + sum -= MULT16_16(den[j],mem[j]); + } + for (j=ord-1;j>=1;j--) + { + mem[j]=mem[j-1]; + } + mem[0] = ROUND16(sum,SIG_SHIFT); + _y[i] = sum; + } +#else + int i,j; + VARDECL(opus_val16, rden); + VARDECL(opus_val16, y); + SAVE_STACK; + + celt_assert((ord&3)==0); + ALLOC(rden, ord, opus_val16); + ALLOC(y, N+ord, opus_val16); + for(i=0;i<ord;i++) + rden[i] = den[ord-i-1]; + for(i=0;i<ord;i++) + y[i] = -mem[ord-i-1]; + for(;i<N+ord;i++) + y[i]=0; + for (i=0;i<N-3;i+=4) + { + /* Unroll by 4 as if it were an FIR filter */ + opus_val32 sum[4]; + sum[0]=_x[i]; + sum[1]=_x[i+1]; + sum[2]=_x[i+2]; + sum[3]=_x[i+3]; + xcorr_kernel(rden, y+i, sum, ord, arch); + + /* Patch up the result to compensate for the fact that this is an IIR */ + y[i+ord ] = -ROUND16(sum[0],SIG_SHIFT); + _y[i ] = sum[0]; + sum[1] = MAC16_16(sum[1], y[i+ord ], den[0]); + y[i+ord+1] = -ROUND16(sum[1],SIG_SHIFT); + _y[i+1] = sum[1]; + sum[2] = MAC16_16(sum[2], y[i+ord+1], den[0]); + sum[2] = MAC16_16(sum[2], y[i+ord ], den[1]); + y[i+ord+2] = -ROUND16(sum[2],SIG_SHIFT); + _y[i+2] = sum[2]; + + sum[3] = MAC16_16(sum[3], y[i+ord+2], den[0]); + sum[3] = MAC16_16(sum[3], y[i+ord+1], den[1]); + sum[3] = MAC16_16(sum[3], y[i+ord ], den[2]); + y[i+ord+3] = -ROUND16(sum[3],SIG_SHIFT); + _y[i+3] = sum[3]; + } + for (;i<N;i++) + { + opus_val32 sum = _x[i]; + for (j=0;j<ord;j++) + sum -= MULT16_16(rden[j],y[i+j]); + y[i+ord] = ROUND16(sum,SIG_SHIFT); + _y[i] = sum; + } + for(i=0;i<ord;i++) + mem[i] = _y[N-i-1]; + RESTORE_STACK; +#endif +} + +int _celt_autocorr( + const opus_val16 *x, /* in: [0...n-1] samples x */ + opus_val32 *ac, /* out: [0...lag-1] ac values */ + const opus_val16 *window, + int overlap, + int lag, + int n, + int arch + ) +{ + opus_val32 d; + int i, k; + int fastN=n-lag; + int shift; + const opus_val16 *xptr; + VARDECL(opus_val16, xx); + SAVE_STACK; + ALLOC(xx, n, opus_val16); + celt_assert(n>0); + celt_assert(overlap>=0); + if (overlap == 0) + { + xptr = x; + } else { + for (i=0;i<n;i++) + xx[i] = x[i]; + for (i=0;i<overlap;i++) + { + xx[i] = MULT16_16_Q15(x[i],window[i]); + xx[n-i-1] = MULT16_16_Q15(x[n-i-1],window[i]); + } + xptr = xx; + } + shift=0; +#ifdef FIXED_POINT + { + opus_val32 ac0; + ac0 = 1+(n<<7); + if (n&1) ac0 += SHR32(MULT16_16(xptr[0],xptr[0]),9); + for(i=(n&1);i<n;i+=2) + { + ac0 += SHR32(MULT16_16(xptr[i],xptr[i]),9); + ac0 += SHR32(MULT16_16(xptr[i+1],xptr[i+1]),9); + } + + shift = celt_ilog2(ac0)-30+10; + shift = (shift)/2; + if (shift>0) + { + for(i=0;i<n;i++) + xx[i] = PSHR32(xptr[i], shift); + xptr = xx; + } else + shift = 0; + } +#endif + celt_pitch_xcorr(xptr, xptr, ac, fastN, lag+1, arch); + for (k=0;k<=lag;k++) + { + for (i = k+fastN, d = 0; i < n; i++) + d = MAC16_16(d, xptr[i], xptr[i-k]); + ac[k] += d; + } +#ifdef FIXED_POINT + shift = 2*shift; + if (shift<=0) + ac[0] += SHL32((opus_int32)1, -shift); + if (ac[0] < 268435456) + { + int shift2 = 29 - EC_ILOG(ac[0]); + for (i=0;i<=lag;i++) + ac[i] = SHL32(ac[i], shift2); + shift -= shift2; + } else if (ac[0] >= 536870912) + { + int shift2=1; + if (ac[0] >= 1073741824) + shift2++; + for (i=0;i<=lag;i++) + ac[i] = SHR32(ac[i], shift2); + shift += shift2; + } +#endif + + RESTORE_STACK; + return shift; +} |