mirror of
https://github.com/mollyim/webrtc.git
synced 2025-05-16 07:10:38 +01:00
bc0b37c08a
This CL defines SpectralFeaturesExtractor which is responsible for computing the spectral features used as input for the RNN. Bug: webrtc:9076 Change-Id: I5e1396b89eca9c13bb268e8419a16436a9c3450f Reviewed-on: https://webrtc-review.googlesource.com/73760 Commit-Queue: Alessio Bazzica <alessiob@webrtc.org> Reviewed-by: Alex Loiko <aleloi@webrtc.org> Reviewed-by: Ivo Creusen <ivoc@webrtc.org> Cr-Commit-Position: refs/heads/master@{#23206}
67 lines
2.7 KiB
C++
67 lines
2.7 KiB
C++
/*
|
|
* Copyright (c) 2018 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_AGC2_RNN_VAD_COMMON_H_
|
|
#define MODULES_AUDIO_PROCESSING_AGC2_RNN_VAD_COMMON_H_
|
|
|
|
namespace webrtc {
|
|
namespace rnn_vad {
|
|
|
|
constexpr double kPi = 3.14159265358979323846;
|
|
|
|
constexpr size_t kSampleRate24kHz = 24000;
|
|
constexpr size_t kFrameSize10ms24kHz = kSampleRate24kHz / 100;
|
|
constexpr size_t kFrameSize20ms24kHz = kFrameSize10ms24kHz * 2;
|
|
|
|
// Pitch analysis params.
|
|
constexpr size_t kMinPitch24kHz = kSampleRate24kHz / 800; // 0.00125 s.
|
|
constexpr size_t kMaxPitch24kHz = kSampleRate24kHz / 62.5; // 0.016 s.
|
|
constexpr size_t kBufSize24kHz = kMaxPitch24kHz + kFrameSize20ms24kHz;
|
|
static_assert((kBufSize24kHz & 1) == 0, "The buffer size must be even.");
|
|
|
|
// Define a higher minimum pitch period for the initial search. This is used to
|
|
// avoid searching for very short periods, for which a refinement step is
|
|
// responsible.
|
|
constexpr size_t kInitialMinPitch24kHz = 3 * kMinPitch24kHz;
|
|
static_assert(kMinPitch24kHz < kInitialMinPitch24kHz, "");
|
|
static_assert(kInitialMinPitch24kHz < kMaxPitch24kHz, "");
|
|
|
|
// 12 kHz analysis.
|
|
constexpr size_t kSampleRate12kHz = 12000;
|
|
constexpr size_t kFrameSize10ms12kHz = kSampleRate12kHz / 100;
|
|
constexpr size_t kFrameSize20ms12kHz = kFrameSize10ms12kHz * 2;
|
|
constexpr size_t kBufSize12kHz = kBufSize24kHz / 2;
|
|
constexpr size_t kInitialMinPitch12kHz = kInitialMinPitch24kHz / 2;
|
|
constexpr size_t kMaxPitch12kHz = kMaxPitch24kHz / 2;
|
|
|
|
// 48 kHz constants.
|
|
constexpr size_t kMinPitch48kHz = kMinPitch24kHz * 2;
|
|
constexpr size_t kMaxPitch48kHz = kMaxPitch24kHz * 2;
|
|
|
|
// Sub-band frequency boundaries.
|
|
constexpr size_t kNumBands = 22;
|
|
constexpr int kBandFrequencyBoundaries[kNumBands] = {
|
|
0, 200, 400, 600, 800, 1000, 1200, 1400, 1600, 2000, 2400,
|
|
2800, 3200, 4000, 4800, 5600, 6800, 8000, 9600, 12000, 15600, 20000};
|
|
|
|
// Feature extraction parameters.
|
|
constexpr size_t kNumLowerBands = 6;
|
|
static_assert((0 < kNumLowerBands) && (kNumLowerBands < kNumBands), "");
|
|
constexpr size_t kSpectralCoeffsHistorySize = 8;
|
|
static_assert(kSpectralCoeffsHistorySize > 2,
|
|
"The history size must at least be 3 to compute first and second "
|
|
"derivatives.");
|
|
|
|
constexpr size_t kFeatureVectorSize = 42;
|
|
|
|
} // namespace rnn_vad
|
|
} // namespace webrtc
|
|
|
|
#endif // MODULES_AUDIO_PROCESSING_AGC2_RNN_VAD_COMMON_H_
|