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Diffstat (limited to 'third_party/webrtc/src/webrtc/modules/audio_processing/utility/delay_estimator.h')
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diff --git a/third_party/webrtc/src/webrtc/modules/audio_processing/utility/delay_estimator.h b/third_party/webrtc/src/webrtc/modules/audio_processing/utility/delay_estimator.h new file mode 100644 index 00000000..65c3f034 --- /dev/null +++ b/third_party/webrtc/src/webrtc/modules/audio_processing/utility/delay_estimator.h @@ -0,0 +1,251 @@ +/* + * Copyright (c) 2012 The WebRTC project authors. All Rights Reserved. + * + * Use of this source code is governed by a BSD-style license + * that can be found in the LICENSE file in the root of the source + * tree. An additional intellectual property rights grant can be found + * in the file PATENTS. All contributing project authors may + * be found in the AUTHORS file in the root of the source tree. + */ + +// Performs delay estimation on binary converted spectra. +// The return value is 0 - OK and -1 - Error, unless otherwise stated. + +#ifndef WEBRTC_MODULES_AUDIO_PROCESSING_UTILITY_DELAY_ESTIMATOR_H_ +#define WEBRTC_MODULES_AUDIO_PROCESSING_UTILITY_DELAY_ESTIMATOR_H_ + +#include "webrtc/typedefs.h" + +static const int32_t kMaxBitCountsQ9 = (32 << 9); // 32 matching bits in Q9. + +typedef struct { + // Pointer to bit counts. + int* far_bit_counts; + // Binary history variables. + uint32_t* binary_far_history; + int history_size; +} BinaryDelayEstimatorFarend; + +typedef struct { + // Pointer to bit counts. + int32_t* mean_bit_counts; + // Array only used locally in ProcessBinarySpectrum() but whose size is + // determined at run-time. + int32_t* bit_counts; + + // Binary history variables. + uint32_t* binary_near_history; + int near_history_size; + int history_size; + + // Delay estimation variables. + int32_t minimum_probability; + int last_delay_probability; + + // Delay memory. + int last_delay; + + // Robust validation + int robust_validation_enabled; + int allowed_offset; + int last_candidate_delay; + int compare_delay; + int candidate_hits; + float* histogram; + float last_delay_histogram; + + // For dynamically changing the lookahead when using SoftReset...(). + int lookahead; + + // Far-end binary spectrum history buffer etc. + BinaryDelayEstimatorFarend* farend; +} BinaryDelayEstimator; + +// Releases the memory allocated by +// WebRtc_CreateBinaryDelayEstimatorFarend(...). +// Input: +// - self : Pointer to the binary delay estimation far-end +// instance which is the return value of +// WebRtc_CreateBinaryDelayEstimatorFarend(). +// +void WebRtc_FreeBinaryDelayEstimatorFarend(BinaryDelayEstimatorFarend* self); + +// Allocates the memory needed by the far-end part of the binary delay +// estimation. The memory needs to be initialized separately through +// WebRtc_InitBinaryDelayEstimatorFarend(...). +// +// Inputs: +// - history_size : Size of the far-end binary spectrum history. +// +// Return value: +// - BinaryDelayEstimatorFarend* +// : Created |handle|. If the memory can't be allocated +// or if any of the input parameters are invalid NULL +// is returned. +// +BinaryDelayEstimatorFarend* WebRtc_CreateBinaryDelayEstimatorFarend( + int history_size); + +// Re-allocates the buffers. +// +// Inputs: +// - self : Pointer to the binary estimation far-end instance +// which is the return value of +// WebRtc_CreateBinaryDelayEstimatorFarend(). +// - history_size : Size of the far-end binary spectrum history. +// +// Return value: +// - history_size : The history size allocated. +int WebRtc_AllocateFarendBufferMemory(BinaryDelayEstimatorFarend* self, + int history_size); + +// Initializes the delay estimation far-end instance created with +// WebRtc_CreateBinaryDelayEstimatorFarend(...). +// +// Input: +// - self : Pointer to the delay estimation far-end instance. +// +// Output: +// - self : Initialized far-end instance. +// +void WebRtc_InitBinaryDelayEstimatorFarend(BinaryDelayEstimatorFarend* self); + +// Soft resets the delay estimation far-end instance created with +// WebRtc_CreateBinaryDelayEstimatorFarend(...). +// +// Input: +// - delay_shift : The amount of blocks to shift history buffers. +// +void WebRtc_SoftResetBinaryDelayEstimatorFarend( + BinaryDelayEstimatorFarend* self, int delay_shift); + +// Adds the binary far-end spectrum to the internal far-end history buffer. This +// spectrum is used as reference when calculating the delay using +// WebRtc_ProcessBinarySpectrum(). +// +// Inputs: +// - self : Pointer to the delay estimation far-end +// instance. +// - binary_far_spectrum : Far-end binary spectrum. +// +// Output: +// - self : Updated far-end instance. +// +void WebRtc_AddBinaryFarSpectrum(BinaryDelayEstimatorFarend* self, + uint32_t binary_far_spectrum); + +// Releases the memory allocated by WebRtc_CreateBinaryDelayEstimator(...). +// +// Note that BinaryDelayEstimator utilizes BinaryDelayEstimatorFarend, but does +// not take ownership of it, hence the BinaryDelayEstimator has to be torn down +// before the far-end. +// +// Input: +// - self : Pointer to the binary delay estimation instance +// which is the return value of +// WebRtc_CreateBinaryDelayEstimator(). +// +void WebRtc_FreeBinaryDelayEstimator(BinaryDelayEstimator* self); + +// Allocates the memory needed by the binary delay estimation. The memory needs +// to be initialized separately through WebRtc_InitBinaryDelayEstimator(...). +// +// See WebRtc_CreateDelayEstimator(..) in delay_estimator_wrapper.c for detailed +// description. +BinaryDelayEstimator* WebRtc_CreateBinaryDelayEstimator( + BinaryDelayEstimatorFarend* farend, int max_lookahead); + +// Re-allocates |history_size| dependent buffers. The far-end buffers will be +// updated at the same time if needed. +// +// Input: +// - self : Pointer to the binary estimation instance which is +// the return value of +// WebRtc_CreateBinaryDelayEstimator(). +// - history_size : Size of the history buffers. +// +// Return value: +// - history_size : The history size allocated. +int WebRtc_AllocateHistoryBufferMemory(BinaryDelayEstimator* self, + int history_size); + +// Initializes the delay estimation instance created with +// WebRtc_CreateBinaryDelayEstimator(...). +// +// Input: +// - self : Pointer to the delay estimation instance. +// +// Output: +// - self : Initialized instance. +// +void WebRtc_InitBinaryDelayEstimator(BinaryDelayEstimator* self); + +// Soft resets the delay estimation instance created with +// WebRtc_CreateBinaryDelayEstimator(...). +// +// Input: +// - delay_shift : The amount of blocks to shift history buffers. +// +// Return value: +// - actual_shifts : The actual number of shifts performed. +// +int WebRtc_SoftResetBinaryDelayEstimator(BinaryDelayEstimator* self, + int delay_shift); + +// Estimates and returns the delay between the binary far-end and binary near- +// end spectra. It is assumed the binary far-end spectrum has been added using +// WebRtc_AddBinaryFarSpectrum() prior to this call. The value will be offset by +// the lookahead (i.e. the lookahead should be subtracted from the returned +// value). +// +// Inputs: +// - self : Pointer to the delay estimation instance. +// - binary_near_spectrum : Near-end binary spectrum of the current block. +// +// Output: +// - self : Updated instance. +// +// Return value: +// - delay : >= 0 - Calculated delay value. +// -2 - Insufficient data for estimation. +// +int WebRtc_ProcessBinarySpectrum(BinaryDelayEstimator* self, + uint32_t binary_near_spectrum); + +// Returns the last calculated delay updated by the function +// WebRtc_ProcessBinarySpectrum(...). +// +// Input: +// - self : Pointer to the delay estimation instance. +// +// Return value: +// - delay : >= 0 - Last calculated delay value +// -2 - Insufficient data for estimation. +// +int WebRtc_binary_last_delay(BinaryDelayEstimator* self); + +// Returns the estimation quality of the last calculated delay updated by the +// function WebRtc_ProcessBinarySpectrum(...). The estimation quality is a value +// in the interval [0, 1]. The higher the value, the better the quality. +// +// Return value: +// - delay_quality : >= 0 - Estimation quality of last calculated +// delay value. +float WebRtc_binary_last_delay_quality(BinaryDelayEstimator* self); + +// Updates the |mean_value| recursively with a step size of 2^-|factor|. This +// function is used internally in the Binary Delay Estimator as well as the +// Fixed point wrapper. +// +// Inputs: +// - new_value : The new value the mean should be updated with. +// - factor : The step size, in number of right shifts. +// +// Input/Output: +// - mean_value : Pointer to the mean value. +// +void WebRtc_MeanEstimatorFix(int32_t new_value, + int factor, + int32_t* mean_value); + +#endif // WEBRTC_MODULES_AUDIO_PROCESSING_UTILITY_DELAY_ESTIMATOR_H_ |