| /* |
| * 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 WEBRTC_MODULES_AUDIO_CODING_NETEQ_COMFORT_NOISE_H_ |
| #define WEBRTC_MODULES_AUDIO_CODING_NETEQ_COMFORT_NOISE_H_ |
| |
| #include "webrtc/base/constructormagic.h" |
| #include "webrtc/modules/audio_coding/neteq/audio_multi_vector.h" |
| #include "webrtc/typedefs.h" |
| |
| namespace webrtc { |
| |
| // Forward declarations. |
| class DecoderDatabase; |
| class SyncBuffer; |
| struct Packet; |
| |
| // This class acts as an interface to the CNG generator. |
| class ComfortNoise { |
| public: |
| enum ReturnCodes { |
| kOK = 0, |
| kUnknownPayloadType, |
| kInternalError, |
| kMultiChannelNotSupported |
| }; |
| |
| ComfortNoise(int fs_hz, DecoderDatabase* decoder_database, |
| SyncBuffer* sync_buffer) |
| : fs_hz_(fs_hz), |
| first_call_(true), |
| overlap_length_(5 * fs_hz_ / 8000), |
| decoder_database_(decoder_database), |
| sync_buffer_(sync_buffer) { |
| } |
| |
| // Resets the state. Should be called before each new comfort noise period. |
| void Reset(); |
| |
| // Update the comfort noise generator with the parameters in |packet|. |
| // Will delete the packet. |
| int UpdateParameters(Packet* packet); |
| |
| // Generates |requested_length| samples of comfort noise and writes to |
| // |output|. If this is the first in call after Reset (or first after creating |
| // the object), it will also mix in comfort noise at the end of the |
| // SyncBuffer object provided in the constructor. |
| int Generate(size_t requested_length, AudioMultiVector* output); |
| |
| // Returns the last error code that was produced by the comfort noise |
| // decoder. Returns 0 if no error has been encountered since the last reset. |
| int internal_error_code() { return internal_error_code_; } |
| |
| private: |
| int fs_hz_; |
| bool first_call_; |
| size_t overlap_length_; |
| DecoderDatabase* decoder_database_; |
| SyncBuffer* sync_buffer_; |
| int internal_error_code_; |
| RTC_DISALLOW_COPY_AND_ASSIGN(ComfortNoise); |
| }; |
| |
| } // namespace webrtc |
| #endif // WEBRTC_MODULES_AUDIO_CODING_NETEQ_COMFORT_NOISE_H_ |