diff options
Diffstat (limited to 'pjmedia/src/pjmedia-codec/speex/ltp.c')
| -rw-r--r-- | pjmedia/src/pjmedia-codec/speex/ltp.c | 96 |
1 files changed, 86 insertions, 10 deletions
diff --git a/pjmedia/src/pjmedia-codec/speex/ltp.c b/pjmedia/src/pjmedia-codec/speex/ltp.c index 009923de..1801bd25 100644 --- a/pjmedia/src/pjmedia-codec/speex/ltp.c +++ b/pjmedia/src/pjmedia-codec/speex/ltp.c @@ -1,4 +1,4 @@ -/* Copyright (C) 2002 Jean-Marc Valin +/* Copyright (C) 2002-2006 Jean-Marc Valin File: ltp.c Long-Term Prediction functions @@ -152,7 +152,7 @@ void pitch_xcorr(const spx_word16_t *_x, const spx_word16_t *_y, spx_word32_t *c #endif #ifndef OVERRIDE_COMPUTE_PITCH_ERROR -PJ_INLINE(spx_word32_t) compute_pitch_error(spx_word16_t *C, spx_word16_t *g, spx_word16_t pitch_control) +static inline spx_word32_t compute_pitch_error(spx_word16_t *C, spx_word16_t *g, spx_word16_t pitch_control) { spx_word32_t sum = 0; sum = ADD32(sum,MULT16_16(MULT16_16_16(g[0],pitch_control),C[0])); @@ -177,7 +177,10 @@ void open_loop_nbest_pitch(spx_word16_t *sw, int start, int end, int len, int *p spx_word32_t e0; VARDECL(spx_word32_t *corr); VARDECL(spx_word32_t *energy); - +#ifdef FIXED_POINT + int scaledown = 0; +#endif + ALLOC(best_score, N, spx_word32_t); ALLOC(best_ener, N, spx_word32_t); ALLOC(corr, end-start+1, spx_word32_t); @@ -189,7 +192,24 @@ void open_loop_nbest_pitch(spx_word16_t *sw, int start, int end, int len, int *p best_ener[i]=0; pitch[i]=start; } - +#ifdef FIXED_POINT + for (i=-end;i<len;i++) + { + if (ABS16(sw[i])>16383) + { + scaledown=1; + break; + } + } + /* If the weighted input is close to saturation, then we scale it down */ + if (scaledown) + { + for (i=-end;i<len;i++) + { + sw[i]=SHR16(sw[i],1); + } + } +#endif energy[0]=inner_prod(sw-start, sw-start, len); e0=inner_prod(sw, sw, len); for (i=start;i<end;i++) @@ -201,6 +221,16 @@ void open_loop_nbest_pitch(spx_word16_t *sw, int start, int end, int len, int *p } pitch_xcorr(sw, sw-end, corr, len, end-start+1, stack); +#ifdef FIXED_POINT + /* If we scaled weighted input down, we need to scale it up again (OK, so we've just lost the LSB, who cares?) */ + if (scaledown) + { + for (i=-end;i<len;i++) + { + sw[i]=SHL16(sw[i],1); + } + } +#endif /* FIXME: Fixed-point and floating-point code should be merged */ #ifdef FIXED_POINT @@ -342,7 +372,8 @@ const spx_word16_t *r, spx_word16_t *new_target, int *cdbk_index, int plc_tuning, -spx_word32_t cumul_gain +spx_word32_t cumul_gain, +int scaledown ) { int i,j; @@ -366,6 +397,9 @@ spx_word32_t cumul_gain x[1]=tmp1+nsf; x[2]=tmp1+2*nsf; + for (j=0;j<nsf;j++) + new_target[j] = target[j]; + { VARDECL(spx_mem_t *mm); int pp=pitch-1; @@ -379,6 +413,16 @@ spx_word32_t cumul_gain else e[j]=0; } +#ifdef FIXED_POINT + /* Scale target and excitation down if needed (avoiding overflow) */ + if (scaledown) + { + for (j=0;j<nsf;j++) + e[j] = SHR16(e[j],1); + for (j=0;j<nsf;j++) + new_target[j] = SHR16(new_target[j],1); + } +#endif for (j=0;j<p;j++) mm[j] = 0; iir_mem16(e, ak, e, nsf, p, mm, stack); @@ -391,13 +435,18 @@ spx_word32_t cumul_gain for (i=1;i>=0;i--) { spx_word16_t e0=exc2[-pitch-1+i]; +#ifdef FIXED_POINT + /* Scale excitation down if needed (avoiding overflow) */ + if (scaledown) + e0 = SHR16(e0,1); +#endif x[i][0]=MULT16_16_Q14(r[0], e0); for (j=0;j<nsf-1;j++) x[i][j+1]=ADD32(x[i+1][j],MULT16_16_P14(r[j+1], e0)); } for (i=0;i<3;i++) - corr[i]=inner_prod(x[i],target,nsf); + corr[i]=inner_prod(x[i],new_target,nsf); for (i=0;i<3;i++) for (j=0;j<=i;j++) A[i][j]=A[j][i]=inner_prod(x[i],x[j],nsf); @@ -478,7 +527,7 @@ spx_word32_t cumul_gain { spx_word32_t tmp = ADD32(ADD32(MULT16_16(gain[0],x[2][i]),MULT16_16(gain[1],x[1][i])), MULT16_16(gain[2],x[0][i])); - new_target[i] = SUB16(target[i], EXTRACT16(PSHR32(tmp,6))); + new_target[i] = SUB16(new_target[i], EXTRACT16(PSHR32(tmp,6))); } err = inner_prod(new_target, new_target, nsf); @@ -520,7 +569,8 @@ spx_word32_t *cumul_gain const ltp_params *params; const signed char *gain_cdbk; int gain_cdbk_size; - + int scaledown=0; + VARDECL(int *nbest); params = (const ltp_params*) par; @@ -545,6 +595,25 @@ spx_word32_t *cumul_gain return start; } +#ifdef FIXED_POINT + /* Check if we need to scale everything down in the pitch search to avoid overflows */ + for (i=0;i<nsf;i++) + { + if (ABS16(target[i])>16383) + { + scaledown=1; + break; + } + } + for (i=-end;i<nsf;i++) + { + if (ABS16(exc2[i])>16383) + { + scaledown=1; + break; + } + } +#endif if (N>end-start+1) N=end-start+1; if (end != start) @@ -562,7 +631,7 @@ spx_word32_t *cumul_gain for (j=0;j<nsf;j++) exc[j]=0; err=pitch_gain_search_3tap(target, ak, awk1, awk2, exc, gain_cdbk, gain_cdbk_size, pitch, p, nsf, - bits, stack, exc2, r, new_target, &cdbk_index, plc_tuning, *cumul_gain); + bits, stack, exc2, r, new_target, &cdbk_index, plc_tuning, *cumul_gain, scaledown); if (err<best_err || best_err<0) { for (j=0;j<nsf;j++) @@ -588,7 +657,14 @@ spx_word32_t *cumul_gain exc[i]=best_exc[i]; for (i=0;i<nsf;i++) target[i]=best_target[i]; - +#ifdef FIXED_POINT + /* Scale target back up if needed */ + if (scaledown) + { + for (i=0;i<nsf;i++) + target[i]=SHL16(target[i],1); + } +#endif return pitch; } |