chromium/third_party/webrtc/modules/audio_processing/aec3/matched_filter.h

/*
 *  Copyright (c) 2017 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.
 */

#ifndef MODULES_AUDIO_PROCESSING_AEC3_MATCHED_FILTER_H_
#define MODULES_AUDIO_PROCESSING_AEC3_MATCHED_FILTER_H_

#include <stddef.h>

#include <vector>

#include "absl/types/optional.h"
#include "api/array_view.h"
#include "modules/audio_processing/aec3/aec3_common.h"
#include "rtc_base/gtest_prod_util.h"
#include "rtc_base/system/arch.h"

namespace webrtc {

class ApmDataDumper;
struct DownsampledRenderBuffer;

namespace aec3 {

#if defined(WEBRTC_HAS_NEON)

// Filter core for the matched filter that is optimized for NEON.
void MatchedFilterCore_NEON(size_t x_start_index,
                            float x2_sum_threshold,
                            float smoothing,
                            rtc::ArrayView<const float> x,
                            rtc::ArrayView<const float> y,
                            rtc::ArrayView<float> h,
                            bool* filters_updated,
                            float* error_sum,
                            bool compute_accumulation_error,
                            rtc::ArrayView<float> accumulated_error,
                            rtc::ArrayView<float> scratch_memory);

#endif

#if defined(WEBRTC_ARCH_X86_FAMILY)

// Filter core for the matched filter that is optimized for SSE2.
void MatchedFilterCore_SSE2(size_t x_start_index,
                            float x2_sum_threshold,
                            float smoothing,
                            rtc::ArrayView<const float> x,
                            rtc::ArrayView<const float> y,
                            rtc::ArrayView<float> h,
                            bool* filters_updated,
                            float* error_sum,
                            bool compute_accumulated_error,
                            rtc::ArrayView<float> accumulated_error,
                            rtc::ArrayView<float> scratch_memory);

// Filter core for the matched filter that is optimized for AVX2.
void MatchedFilterCore_AVX2(size_t x_start_index,
                            float x2_sum_threshold,
                            float smoothing,
                            rtc::ArrayView<const float> x,
                            rtc::ArrayView<const float> y,
                            rtc::ArrayView<float> h,
                            bool* filters_updated,
                            float* error_sum,
                            bool compute_accumulated_error,
                            rtc::ArrayView<float> accumulated_error,
                            rtc::ArrayView<float> scratch_memory);

#endif

// Filter core for the matched filter.
void MatchedFilterCore(size_t x_start_index,
                       float x2_sum_threshold,
                       float smoothing,
                       rtc::ArrayView<const float> x,
                       rtc::ArrayView<const float> y,
                       rtc::ArrayView<float> h,
                       bool* filters_updated,
                       float* error_sum,
                       bool compute_accumulation_error,
                       rtc::ArrayView<float> accumulated_error);

// Find largest peak of squared values in array.
size_t MaxSquarePeakIndex(rtc::ArrayView<const float> h);

}  // namespace aec3

// Produces recursively updated cross-correlation estimates for several signal
// shifts where the intra-shift spacing is uniform.
class MatchedFilter { … };

}  // namespace webrtc

#endif  // MODULES_AUDIO_PROCESSING_AEC3_MATCHED_FILTER_H_