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 * This file contains the function WebRtcSpl_GetScalingSquare(). 14 * The description header can be found in signal_processing_library.h 15 * 16 */ 17 18 #include "webrtc/common_audio/signal_processing/include/signal_processing_library.h" 19 20 int16_t WebRtcSpl_GetScalingSquare(int16_t* in_vector, 21 size_t in_vector_length, 22 size_t times) 23 { 24 int16_t nbits = WebRtcSpl_GetSizeInBits((uint32_t)times); 25 size_t i; 26 int16_t smax = -1; 27 int16_t sabs; 28 int16_t *sptr = in_vector; 29 int16_t t; 30 size_t looptimes = in_vector_length; 31 32 for (i = looptimes; i > 0; i--) 33 { 34 sabs = (*sptr > 0 ? *sptr++ : -*sptr++); 35 smax = (sabs > smax ? sabs : smax); 36 } 37 t = WebRtcSpl_NormW32(WEBRTC_SPL_MUL(smax, smax)); 38 39 if (smax == 0) 40 { 41 return 0; // Since norm(0) returns 0 42 } else 43 { 44 return (t > nbits) ? 0 : nbits - t; 45 } 46 } 47
