diff options
Diffstat (limited to 'media/libstagefright/codecs/amrwbenc/src/autocorr.c')
| -rw-r--r-- | media/libstagefright/codecs/amrwbenc/src/autocorr.c | 182 |
1 files changed, 91 insertions, 91 deletions
diff --git a/media/libstagefright/codecs/amrwbenc/src/autocorr.c b/media/libstagefright/codecs/amrwbenc/src/autocorr.c index 0b2ea89..3ea53f7 100644 --- a/media/libstagefright/codecs/amrwbenc/src/autocorr.c +++ b/media/libstagefright/codecs/amrwbenc/src/autocorr.c @@ -31,100 +31,100 @@ #define UNUSED(x) (void)(x) void Autocorr( - Word16 x[], /* (i) : Input signal */ - Word16 m, /* (i) : LPC order */ - Word16 r_h[], /* (o) Q15: Autocorrelations (msb) */ - Word16 r_l[] /* (o) : Autocorrelations (lsb) */ - ) + Word16 x[], /* (i) : Input signal */ + Word16 m, /* (i) : LPC order */ + Word16 r_h[], /* (o) Q15: Autocorrelations (msb) */ + Word16 r_l[] /* (o) : Autocorrelations (lsb) */ + ) { - Word32 i, norm, shift; - Word16 y[L_WINDOW]; - Word32 L_sum, L_sum1, L_tmp, F_LEN; - Word16 *p1,*p2,*p3; - const Word16 *p4; + Word32 i, norm, shift; + Word16 y[L_WINDOW]; + Word32 L_sum, L_sum1, L_tmp, F_LEN; + Word16 *p1,*p2,*p3; + const Word16 *p4; UNUSED(m); - /* Windowing of signal */ - p1 = x; - p4 = vo_window; - p3 = y; - - for (i = 0; i < L_WINDOW; i+=4) - { - *p3++ = vo_mult_r((*p1++), (*p4++)); - *p3++ = vo_mult_r((*p1++), (*p4++)); - *p3++ = vo_mult_r((*p1++), (*p4++)); - *p3++ = vo_mult_r((*p1++), (*p4++)); - } - - /* calculate energy of signal */ - L_sum = vo_L_deposit_h(16); /* sqrt(256), avoid overflow after rounding */ - for (i = 0; i < L_WINDOW; i++) - { - L_tmp = vo_L_mult(y[i], y[i]); - L_tmp = (L_tmp >> 8); - L_sum += L_tmp; - } - - /* scale signal to avoid overflow in autocorrelation */ - norm = norm_l(L_sum); - shift = 4 - (norm >> 1); - if(shift > 0) - { - p1 = y; - for (i = 0; i < L_WINDOW; i+=4) - { - *p1 = vo_shr_r(*p1, shift); - p1++; - *p1 = vo_shr_r(*p1, shift); - p1++; - *p1 = vo_shr_r(*p1, shift); - p1++; - *p1 = vo_shr_r(*p1, shift); - p1++; - } - } - - /* Compute and normalize r[0] */ - L_sum = 1; - for (i = 0; i < L_WINDOW; i+=4) - { - L_sum += vo_L_mult(y[i], y[i]); - L_sum += vo_L_mult(y[i+1], y[i+1]); - L_sum += vo_L_mult(y[i+2], y[i+2]); - L_sum += vo_L_mult(y[i+3], y[i+3]); - } - - norm = norm_l(L_sum); - L_sum = (L_sum << norm); - - r_h[0] = L_sum >> 16; - r_l[0] = (L_sum & 0xffff)>>1; - - /* Compute r[1] to r[m] */ - for (i = 1; i <= 8; i++) - { - L_sum1 = 0; - L_sum = 0; - F_LEN = (Word32)(L_WINDOW - 2*i); - p1 = y; - p2 = y + (2*i)-1; - do{ - L_sum1 += *p1 * *p2++; - L_sum += *p1++ * *p2; - }while(--F_LEN!=0); - - L_sum1 += *p1 * *p2++; - - L_sum1 = L_sum1<<norm; - L_sum = L_sum<<norm; - - r_h[(2*i)-1] = L_sum1 >> 15; - r_l[(2*i)-1] = L_sum1 & 0x00007fff; - r_h[(2*i)] = L_sum >> 15; - r_l[(2*i)] = L_sum & 0x00007fff; - } - return; + /* Windowing of signal */ + p1 = x; + p4 = vo_window; + p3 = y; + + for (i = 0; i < L_WINDOW; i+=4) + { + *p3++ = vo_mult_r((*p1++), (*p4++)); + *p3++ = vo_mult_r((*p1++), (*p4++)); + *p3++ = vo_mult_r((*p1++), (*p4++)); + *p3++ = vo_mult_r((*p1++), (*p4++)); + } + + /* calculate energy of signal */ + L_sum = vo_L_deposit_h(16); /* sqrt(256), avoid overflow after rounding */ + for (i = 0; i < L_WINDOW; i++) + { + L_tmp = vo_L_mult(y[i], y[i]); + L_tmp = (L_tmp >> 8); + L_sum += L_tmp; + } + + /* scale signal to avoid overflow in autocorrelation */ + norm = norm_l(L_sum); + shift = 4 - (norm >> 1); + if(shift > 0) + { + p1 = y; + for (i = 0; i < L_WINDOW; i+=4) + { + *p1 = vo_shr_r(*p1, shift); + p1++; + *p1 = vo_shr_r(*p1, shift); + p1++; + *p1 = vo_shr_r(*p1, shift); + p1++; + *p1 = vo_shr_r(*p1, shift); + p1++; + } + } + + /* Compute and normalize r[0] */ + L_sum = 1; + for (i = 0; i < L_WINDOW; i+=4) + { + L_sum += vo_L_mult(y[i], y[i]); + L_sum += vo_L_mult(y[i+1], y[i+1]); + L_sum += vo_L_mult(y[i+2], y[i+2]); + L_sum += vo_L_mult(y[i+3], y[i+3]); + } + + norm = norm_l(L_sum); + L_sum = (L_sum << norm); + + r_h[0] = L_sum >> 16; + r_l[0] = (L_sum & 0xffff)>>1; + + /* Compute r[1] to r[m] */ + for (i = 1; i <= 8; i++) + { + L_sum1 = 0; + L_sum = 0; + F_LEN = (Word32)(L_WINDOW - 2*i); + p1 = y; + p2 = y + (2*i)-1; + do{ + L_sum1 += *p1 * *p2++; + L_sum += *p1++ * *p2; + }while(--F_LEN!=0); + + L_sum1 += *p1 * *p2++; + + L_sum1 = L_sum1<<norm; + L_sum = L_sum<<norm; + + r_h[(2*i)-1] = L_sum1 >> 15; + r_l[(2*i)-1] = L_sum1 & 0x00007fff; + r_h[(2*i)] = L_sum >> 15; + r_l[(2*i)] = L_sum & 0x00007fff; + } + return; } |