| /* |
| * 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. |
| */ |
| |
| |
| #ifndef MODULES_AUDIO_CODING_CODECS_CNG_WEBRTC_CNG_H_ |
| #define MODULES_AUDIO_CODING_CODECS_CNG_WEBRTC_CNG_H_ |
| |
| #include <cstddef> |
| |
| #include "api/array_view.h" |
| #include "rtc_base/buffer.h" |
| #include "typedefs.h" // NOLINT(build/include) |
| |
| #define WEBRTC_CNG_MAX_LPC_ORDER 12 |
| |
| namespace webrtc { |
| |
| class ComfortNoiseDecoder { |
| public: |
| ComfortNoiseDecoder(); |
| ~ComfortNoiseDecoder() = default; |
| |
| ComfortNoiseDecoder(const ComfortNoiseDecoder&) = delete; |
| ComfortNoiseDecoder& operator=(const ComfortNoiseDecoder&) = delete; |
| |
| void Reset(); |
| |
| // Updates the CN state when a new SID packet arrives. |
| // |sid| is a view of the SID packet without the headers. |
| void UpdateSid(rtc::ArrayView<const uint8_t> sid); |
| |
| // Generates comfort noise. |
| // |out_data| will be filled with samples - its size determines the number of |
| // samples generated. When |new_period| is true, CNG history will be reset |
| // before any audio is generated. Returns |false| if outData is too large - |
| // currently 640 bytes (equalling 10ms at 64kHz). |
| // TODO(ossu): Specify better limits for the size of out_data. Either let it |
| // be unbounded or limit to 10ms in the current sample rate. |
| bool Generate(rtc::ArrayView<int16_t> out_data, bool new_period); |
| |
| private: |
| uint32_t dec_seed_; |
| int32_t dec_target_energy_; |
| int32_t dec_used_energy_; |
| int16_t dec_target_reflCoefs_[WEBRTC_CNG_MAX_LPC_ORDER + 1]; |
| int16_t dec_used_reflCoefs_[WEBRTC_CNG_MAX_LPC_ORDER + 1]; |
| int16_t dec_filtstate_[WEBRTC_CNG_MAX_LPC_ORDER + 1]; |
| int16_t dec_filtstateLow_[WEBRTC_CNG_MAX_LPC_ORDER + 1]; |
| uint16_t dec_order_; |
| int16_t dec_target_scale_factor_; /* Q29 */ |
| int16_t dec_used_scale_factor_; /* Q29 */ |
| }; |
| |
| class ComfortNoiseEncoder { |
| public: |
| // Creates a comfort noise encoder. |
| // |fs| selects sample rate: 8000 for narrowband or 16000 for wideband. |
| // |interval| sets the interval at which to generate SID data (in ms). |
| // |quality| selects the number of refl. coeffs. Maximum allowed is 12. |
| ComfortNoiseEncoder(int fs, int interval, int quality); |
| ~ComfortNoiseEncoder() = default; |
| |
| ComfortNoiseEncoder(const ComfortNoiseEncoder&) = delete; |
| ComfortNoiseEncoder& operator=(const ComfortNoiseEncoder&) = delete; |
| |
| // Resets the comfort noise encoder to its initial state. |
| // Parameters are set as during construction. |
| void Reset(int fs, int interval, int quality); |
| |
| // Analyzes background noise from |speech| and appends coefficients to |
| // |output|. Returns the number of coefficients generated. If |force_sid| is |
| // true, a SID frame is forced and the internal sid interval counter is reset. |
| // Will fail if the input size is too large (> 640 samples, see |
| // ComfortNoiseDecoder::Generate). |
| size_t Encode(rtc::ArrayView<const int16_t> speech, |
| bool force_sid, |
| rtc::Buffer* output); |
| |
| private: |
| size_t enc_nrOfCoefs_; |
| int enc_sampfreq_; |
| int16_t enc_interval_; |
| int16_t enc_msSinceSid_; |
| int32_t enc_Energy_; |
| int16_t enc_reflCoefs_[WEBRTC_CNG_MAX_LPC_ORDER + 1]; |
| int32_t enc_corrVector_[WEBRTC_CNG_MAX_LPC_ORDER + 1]; |
| uint32_t enc_seed_; |
| }; |
| |
| } // namespace webrtc |
| |
| #endif // MODULES_AUDIO_CODING_CODECS_CNG_WEBRTC_CNG_H_ |