1 /* 2 * Copyright (c) 2011 The WebRTC project authors. All Rights Reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 11 /****************************************************************** 12 13 iLBC Speech Coder ANSI-C Source Code 14 15 WebRtcIlbcfix_CbMemEnergyCalc.c 16 17 ******************************************************************/ 18 19 #include "defines.h" 20 21 /* Compute the energy of the rest of the cb memory 22 * by step wise adding and subtracting the next 23 * sample and the last sample respectively */ 24 void WebRtcIlbcfix_CbMemEnergyCalc( 25 int32_t energy, /* (i) input start energy */ 26 int16_t range, /* (i) number of iterations */ 27 int16_t *ppi, /* (i) input pointer 1 */ 28 int16_t *ppo, /* (i) input pointer 2 */ 29 int16_t *energyW16, /* (o) Energy in the CB vectors */ 30 int16_t *energyShifts, /* (o) Shift value of the energy */ 31 int16_t scale, /* (i) The scaling of all energy values */ 32 int16_t base_size /* (i) Index to where the energy values should be stored */ 33 ) 34 { 35 int16_t j,shft; 36 int32_t tmp; 37 int16_t *eSh_ptr; 38 int16_t *eW16_ptr; 39 40 41 eSh_ptr = &energyShifts[1+base_size]; 42 eW16_ptr = &energyW16[1+base_size]; 43 44 for(j=0;j<range-1;j++) { 45 46 /* Calculate next energy by a +/- 47 operation on the edge samples */ 48 tmp = WEBRTC_SPL_MUL_16_16(*ppi, *ppi); 49 tmp -= WEBRTC_SPL_MUL_16_16(*ppo, *ppo); 50 energy += WEBRTC_SPL_RSHIFT_W32(tmp, scale); 51 energy = WEBRTC_SPL_MAX(energy, 0); 52 53 ppi--; 54 ppo--; 55 56 /* Normalize the energy into a int16_t and store 57 the number of shifts */ 58 59 shft = (int16_t)WebRtcSpl_NormW32(energy); 60 *eSh_ptr++ = shft; 61 62 tmp = WEBRTC_SPL_LSHIFT_W32(energy, shft); 63 *eW16_ptr++ = (int16_t)WEBRTC_SPL_RSHIFT_W32(tmp, 16); 64 } 65 } 66
