| /* |
| * Copyright (c) 2014 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 WEBRTC_MODULES_AUDIO_PROCESSING_BEAMFORMER_COVARIANCE_MATRIX_GENERATOR_H_ |
| #define WEBRTC_MODULES_AUDIO_PROCESSING_BEAMFORMER_COVARIANCE_MATRIX_GENERATOR_H_ |
| |
| #include "webrtc/modules/audio_processing/beamformer/complex_matrix.h" |
| #include "webrtc/modules/audio_processing/beamformer/array_util.h" |
| |
| namespace webrtc { |
| |
| // Helper class for Beamformer in charge of generating covariance matrices. For |
| // each function, the passed-in ComplexMatrix is expected to be of size |
| // |num_input_channels| x |num_input_channels|. |
| class CovarianceMatrixGenerator { |
| public: |
| // A uniform covariance matrix with a gap at the target location. WARNING: |
| // The target angle is assumed to be 0. |
| static void UniformCovarianceMatrix(float wave_number, |
| const std::vector<Point>& geometry, |
| ComplexMatrix<float>* mat); |
| |
| // The covariance matrix of a source at the given angle. |
| static void AngledCovarianceMatrix(float sound_speed, |
| float angle, |
| size_t frequency_bin, |
| size_t fft_size, |
| size_t num_freq_bins, |
| int sample_rate, |
| const std::vector<Point>& geometry, |
| ComplexMatrix<float>* mat); |
| |
| // Calculates phase shifts that, when applied to a multichannel signal and |
| // added together, cause constructive interferernce for sources located at |
| // the given angle. |
| static void PhaseAlignmentMasks(size_t frequency_bin, |
| size_t fft_size, |
| int sample_rate, |
| float sound_speed, |
| const std::vector<Point>& geometry, |
| float angle, |
| ComplexMatrix<float>* mat); |
| }; |
| |
| } // namespace webrtc |
| |
| #endif // WEBRTC_MODULES_AUDIO_PROCESSING_BEAMFORMER_BF_HELPERS_H_ |