sum_sqr_shift.c revision 2bd8b54017b5320bc0c1df9bf86f4cdc9f8db242
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 342bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian/* Compute number of bits to right shift the sum of squares of a vector */ 352bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian/* of int16s to make it fit in an int32 */ 362bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanianvoid silk_sum_sqr_shift( 372bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian opus_int32 *energy, /* O Energy of x, after shifting to the right */ 382bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian opus_int *shift, /* O Number of bits right shift applied to energy */ 392bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian const opus_int16 *x, /* I Input vector */ 402bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian opus_int len /* I Length of input vector */ 412bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian) 422bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian{ 432bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian opus_int i, shft; 442bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian opus_int32 nrg_tmp, nrg; 452bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian 462bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian nrg = 0; 472bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian shft = 0; 482bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian len--; 492bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian for( i = 0; i < len; i += 2 ) { 502bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian nrg = silk_SMLABB_ovflw( nrg, x[ i ], x[ i ] ); 512bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian nrg = silk_SMLABB_ovflw( nrg, x[ i + 1 ], x[ i + 1 ] ); 522bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian if( nrg < 0 ) { 532bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian /* Scale down */ 542bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian nrg = (opus_int32)silk_RSHIFT_uint( (opus_uint32)nrg, 2 ); 552bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian shft = 2; 562bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian break; 572bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian } 582bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian } 592bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian for( ; i < len; i += 2 ) { 602bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian nrg_tmp = silk_SMULBB( x[ i ], x[ i ] ); 612bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian nrg_tmp = silk_SMLABB_ovflw( nrg_tmp, x[ i + 1 ], x[ i + 1 ] ); 622bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian nrg = (opus_int32)silk_ADD_RSHIFT_uint( nrg, (opus_uint32)nrg_tmp, shft ); 632bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian if( nrg < 0 ) { 642bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian /* Scale down */ 652bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian nrg = (opus_int32)silk_RSHIFT_uint( (opus_uint32)nrg, 2 ); 662bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian shft += 2; 672bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian } 682bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian } 692bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian if( i == len ) { 702bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian /* One sample left to process */ 712bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian nrg_tmp = silk_SMULBB( x[ i ], x[ i ] ); 722bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian nrg = (opus_int32)silk_ADD_RSHIFT_uint( nrg, nrg_tmp, shft ); 732bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian } 742bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian 752bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian /* Make sure to have at least one extra leading zero (two leading zeros in total) */ 762bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian if( nrg & 0xC0000000 ) { 772bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian nrg = silk_RSHIFT_uint( (opus_uint32)nrg, 2 ); 782bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian shft += 2; 792bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian } 802bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian 812bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian /* Output arguments */ 822bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian *shift = shft; 832bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian *energy = nrg; 842bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian} 852bd8b54017b5320bc0c1df9bf86f4cdc9f8db242Vignesh Venkatasubramanian 86