12bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian/*********************************************************************** 22bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh VenkatasubramanianCopyright (c) 2006-2011, Skype Limited. All rights reserved. 32bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh VenkatasubramanianRedistribution and use in source and binary forms, with or without 42bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanianmodification, are permitted provided that the following conditions 52bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanianare met: 62bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian- Redistributions of source code must retain the above copyright notice, 72bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanianthis list of conditions and the following disclaimer. 82bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian- Redistributions in binary form must reproduce the above copyright 92bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramaniannotice, this list of conditions and the following disclaimer in the 102bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramaniandocumentation and/or other materials provided with the distribution. 112bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian- Neither the name of Internet Society, IETF or IETF Trust, nor the 122bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramaniannames of specific contributors, may be used to endorse or promote 132bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanianproducts derived from this software without specific prior written 142bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanianpermission. 152bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh VenkatasubramanianTHIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 162bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh VenkatasubramanianAND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 172bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh VenkatasubramanianIMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 182bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh VenkatasubramanianARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 192bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh VenkatasubramanianLIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 202bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh VenkatasubramanianCONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 212bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh VenkatasubramanianSUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 222bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh VenkatasubramanianINTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 232bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh VenkatasubramanianCONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 242bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh VenkatasubramanianARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 252bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh VenkatasubramanianPOSSIBILITY OF SUCH DAMAGE. 262bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian***********************************************************************/ 272bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian 282bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian#ifdef HAVE_CONFIG_H 292bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian#include "config.h" 302bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian#endif 312bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian 322bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian#include "SigProc_FIX.h" 332bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian#include "celt_lpc.h" 342bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian 352bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian/*******************************************/ 362bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian/* LPC analysis filter */ 372bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian/* NB! State is kept internally and the */ 382bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian/* filter always starts with zero state */ 392bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian/* first d output samples are set to zero */ 402bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian/*******************************************/ 412bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian 422bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanianvoid silk_LPC_analysis_filter( 432bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian opus_int16 *out, /* O Output signal */ 442bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian const opus_int16 *in, /* I Input signal */ 452bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian const opus_int16 *B, /* I MA prediction coefficients, Q12 [order] */ 462bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian const opus_int32 len, /* I Signal length */ 472bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian const opus_int32 d /* I Filter order */ 482bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian) 492bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian{ 502bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian opus_int j; 512bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian#ifdef FIXED_POINT 522bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian opus_int16 mem[SILK_MAX_ORDER_LPC]; 532bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian opus_int16 num[SILK_MAX_ORDER_LPC]; 542bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian#else 552bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian int ix; 562bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian opus_int32 out32_Q12, out32; 572bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian const opus_int16 *in_ptr; 582bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian#endif 592bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian 602bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian silk_assert( d >= 6 ); 612bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian silk_assert( (d & 1) == 0 ); 622bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian silk_assert( d <= len ); 632bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian 642bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian#ifdef FIXED_POINT 652bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian silk_assert( d <= SILK_MAX_ORDER_LPC ); 662bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian for ( j = 0; j < d; j++ ) { 672bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian num[ j ] = -B[ j ]; 682bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian } 692bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian for (j=0;j<d;j++) { 702bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian mem[ j ] = in[ d - j - 1 ]; 712bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian } 722bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian celt_fir( in + d, num, out + d, len - d, d, mem ); 732bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian for ( j = 0; j < d; j++ ) { 742bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian out[ j ] = 0; 752bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian } 762bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian#else 772bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian for( ix = d; ix < len; ix++ ) { 782bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian in_ptr = &in[ ix - 1 ]; 792bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian 802bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian out32_Q12 = silk_SMULBB( in_ptr[ 0 ], B[ 0 ] ); 812bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian /* Allowing wrap around so that two wraps can cancel each other. The rare 822bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian cases where the result wraps around can only be triggered by invalid streams*/ 832bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian out32_Q12 = silk_SMLABB_ovflw( out32_Q12, in_ptr[ -1 ], B[ 1 ] ); 842bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian out32_Q12 = silk_SMLABB_ovflw( out32_Q12, in_ptr[ -2 ], B[ 2 ] ); 852bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian out32_Q12 = silk_SMLABB_ovflw( out32_Q12, in_ptr[ -3 ], B[ 3 ] ); 862bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian out32_Q12 = silk_SMLABB_ovflw( out32_Q12, in_ptr[ -4 ], B[ 4 ] ); 872bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian out32_Q12 = silk_SMLABB_ovflw( out32_Q12, in_ptr[ -5 ], B[ 5 ] ); 882bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian for( j = 6; j < d; j += 2 ) { 892bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian out32_Q12 = silk_SMLABB_ovflw( out32_Q12, in_ptr[ -j ], B[ j ] ); 902bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian out32_Q12 = silk_SMLABB_ovflw( out32_Q12, in_ptr[ -j - 1 ], B[ j + 1 ] ); 912bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian } 922bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian 932bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian /* Subtract prediction */ 942bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian out32_Q12 = silk_SUB32_ovflw( silk_LSHIFT( (opus_int32)in_ptr[ 1 ], 12 ), out32_Q12 ); 952bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian 962bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian /* Scale to Q0 */ 972bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian out32 = silk_RSHIFT_ROUND( out32_Q12, 12 ); 982bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian 992bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian /* Saturate output */ 1002bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian out[ ix ] = (opus_int16)silk_SAT16( out32 ); 1012bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian } 1022bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian 1032bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian /* Set first d output samples to zero */ 1042bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian silk_memset( out, 0, d * sizeof( opus_int16 ) ); 1052bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian#endif 1062bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian} 107