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 // Performs delay estimation on block by block basis. 12 // The return value is 0 - OK and -1 - Error, unless otherwise stated. 13 14 #ifndef WEBRTC_MODULES_AUDIO_PROCESSING_UTILITY_DELAY_ESTIMATOR_WRAPPER_H_ 15 #define WEBRTC_MODULES_AUDIO_PROCESSING_UTILITY_DELAY_ESTIMATOR_WRAPPER_H_ 16 17 #include "typedefs.h" 18 19 // Releases the memory allocated by WebRtc_CreateDelayEstimator(...) 20 // Input: 21 // - handle : Pointer to the delay estimation instance. 22 // 23 int WebRtc_FreeDelayEstimator(void* handle); 24 25 // Allocates the memory needed by the delay estimation. The memory needs to be 26 // initialized separately through WebRtc_InitDelayEstimator(...). 27 // 28 // Inputs: 29 // - handle : Instance that should be created. 30 // - spectrum_size : Size of the spectrum used both in far-end and 31 // near-end. Used to allocate memory for spectrum 32 // specific buffers. 33 // - max_delay : The maximum delay which can be estimated. Needed to 34 // allocate memory for history buffers. 35 // - lookahead : Amount of non-causal lookahead to use. This can 36 // detect cases in which a near-end signal occurs before 37 // the corresponding far-end signal. It will delay the 38 // estimate for the current block by an equal amount, 39 // and the returned values will be offset by it. 40 // 41 // A value of zero is the typical no-lookahead case. 42 // This also represents the minimum delay which can be 43 // estimated. 44 // 45 // Output: 46 // - handle : Created instance. 47 // 48 int WebRtc_CreateDelayEstimator(void** handle, 49 int spectrum_size, 50 int max_delay, 51 int lookahead); 52 53 // Initializes the delay estimation instance created with 54 // WebRtc_CreateDelayEstimator(...) 55 // Input: 56 // - handle : Pointer to the delay estimation instance. 57 // 58 // Output: 59 // - handle : Initialized instance. 60 // 61 int WebRtc_InitDelayEstimator(void* handle); 62 63 // Estimates and returns the delay between the far-end and near-end blocks. The 64 // value will be offset by the lookahead (i.e. the lookahead should be 65 // subtracted from the returned value). 66 // Inputs: 67 // - handle : Pointer to the delay estimation instance. 68 // - far_spectrum : Pointer to the far-end spectrum data. 69 // - near_spectrum : Pointer to the near-end spectrum data of the current 70 // block. 71 // - spectrum_size : The size of the data arrays (same for both far- and 72 // near-end). 73 // - far_q : The Q-domain of the far-end data. 74 // - near_q : The Q-domain of the near-end data. 75 // 76 // Output: 77 // - handle : Updated instance. 78 // 79 // Return value: 80 // - delay : >= 0 - Calculated delay value. 81 // -1 - Error. 82 // -2 - Insufficient data for estimation. 83 // 84 int WebRtc_DelayEstimatorProcessFix(void* handle, 85 uint16_t* far_spectrum, 86 uint16_t* near_spectrum, 87 int spectrum_size, 88 int far_q, 89 int near_q); 90 91 // See WebRtc_DelayEstimatorProcessFix() for description. 92 int WebRtc_DelayEstimatorProcessFloat(void* handle, 93 float* far_spectrum, 94 float* near_spectrum, 95 int spectrum_size); 96 97 // Returns the last calculated delay updated by the function 98 // WebRtc_DelayEstimatorProcess(...). 99 // 100 // Input: 101 // - handle : Pointer to the delay estimation instance. 102 // 103 // Return value: 104 // - delay : >= 0 - Last calculated delay value. 105 // -1 - Error. 106 // -2 - Insufficient data for estimation. 107 // 108 int WebRtc_last_delay(void* handle); 109 110 #endif // WEBRTC_MODULES_AUDIO_PROCESSING_UTILITY_DELAY_ESTIMATOR_WRAPPER_H_ 111
