Cody Schuffelen | 134ff03 | 2019-11-22 00:25:32 -0800 | [diff] [blame^] | 1 | // Copyright 2018 Google LLC |
| 2 | // |
| 3 | // Licensed under the Apache License, Version 2.0 (the "License"); |
| 4 | // you may not use this file except in compliance with the License. |
| 5 | // You may obtain a copy of the License at |
| 6 | // |
| 7 | // https://www.apache.org/licenses/LICENSE-2.0 |
| 8 | // |
| 9 | // Unless required by applicable law or agreed to in writing, software |
| 10 | // distributed under the License is distributed on an "AS IS" BASIS, |
| 11 | // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 12 | // See the License for the specific language governing permissions and |
| 13 | // limitations under the License. |
| 14 | |
| 15 | // https://github.com/google/opuscpp |
| 16 | |
| 17 | #ifndef OPUSCPP_OPUS_WRAPPER_H_ |
| 18 | #define OPUSCPP_OPUS_WRAPPER_H_ |
| 19 | |
| 20 | #include <memory> |
| 21 | #include <string> |
| 22 | #include <vector> |
| 23 | |
| 24 | #include "opus.h" |
| 25 | |
| 26 | namespace opus { |
| 27 | |
| 28 | std::string ErrorToString(int error); |
| 29 | |
| 30 | namespace internal { |
| 31 | // Deleter for OpusEncoders and OpusDecoders |
| 32 | struct OpusDestroyer { |
| 33 | void operator()(OpusEncoder* encoder) const noexcept; |
| 34 | void operator()(OpusDecoder* decoder) const noexcept; |
| 35 | }; |
| 36 | template <typename T> |
| 37 | using opus_uptr = std::unique_ptr<T, OpusDestroyer>; |
| 38 | } // namespace internal |
| 39 | |
| 40 | class Encoder { |
| 41 | public: |
| 42 | // see documentation at: |
| 43 | // https://mf4.xiph.org/jenkins/view/opus/job/opus/ws/doc/html/group__opus__encoder.html#gaa89264fd93c9da70362a0c9b96b9ca88 |
| 44 | // Fs corresponds to sample_rate |
| 45 | // |
| 46 | // If expected_loss_percent is positive, FEC will be enabled |
| 47 | Encoder(opus_int32 sample_rate, int num_channels, int application, |
| 48 | int expected_loss_percent = 0); |
| 49 | |
| 50 | // Resets internal state of encoder. This should be called between encoding |
| 51 | // different streams so that back-to-back decoding and one-at-a-time decoding |
| 52 | // give the same result. Returns true on success. |
| 53 | bool ResetState(); |
| 54 | |
| 55 | // Sets the desired bitrate. Rates from 500 to 512000 are meaningful as well |
| 56 | // as the special values OPUS_AUTO and OPUS_BITRATE_MAX. If this method |
| 57 | // is not called, the default value of OPUS_AUTO is used. |
| 58 | // Returns true on success. |
| 59 | bool SetBitrate(int bitrate); |
| 60 | |
| 61 | // Enables or disables variable bitrate in the encoder. By default, variable |
| 62 | // bitrate is enabled. Returns true on success. |
| 63 | bool SetVariableBitrate(int vbr); |
| 64 | |
| 65 | // Sets the computational complexity of the encoder, in the range of 0 to 10, |
| 66 | // inclusive, with 10 being the highest complexity. Returns true on success. |
| 67 | bool SetComplexity(int complexity); |
| 68 | |
| 69 | // Gets the total samples of delay added by the entire codec. This value |
| 70 | // is the minimum amount of 'preskip' that has to be specified in an |
| 71 | // ogg-stream that encapsulates the encoded audio. |
| 72 | int GetLookahead(); |
| 73 | |
| 74 | // Takes audio data and encodes it. Returns a sequence of encoded packets. |
| 75 | // pcm.size() must be divisible by frame_size * (number of channels); |
| 76 | // pcm must not contain any incomplete packets. |
| 77 | // see documentation for pcm and frame_size at: |
| 78 | // https://mf4.xiph.org/jenkins/view/opus/job/opus/ws/doc/html/group__opus__encoder.html#gad2d6bf6a9ffb6674879d7605ed073e25 |
| 79 | std::vector<std::vector<unsigned char>> Encode( |
| 80 | const std::vector<opus_int16>& pcm, int frame_size); |
| 81 | |
| 82 | int valid() const { return valid_; } |
| 83 | |
| 84 | private: |
| 85 | std::vector<unsigned char> EncodeFrame( |
| 86 | const std::vector<opus_int16>::const_iterator& frame_start, |
| 87 | int frame_size); |
| 88 | |
| 89 | template <typename... Ts> |
| 90 | int Ctl(int request, Ts... args) const { |
| 91 | return opus_encoder_ctl(encoder_.get(), request, args...); |
| 92 | } |
| 93 | |
| 94 | int num_channels_{}; |
| 95 | bool valid_{}; |
| 96 | internal::opus_uptr<OpusEncoder> encoder_; |
| 97 | }; |
| 98 | |
| 99 | class Decoder { |
| 100 | public: |
| 101 | // see documentation at: |
| 102 | // https://mf4.xiph.org/jenkins/view/opus/job/opus/ws/doc/html/group__opus__decoder.html#ga753f6fe0b699c81cfd47d70c8e15a0bd |
| 103 | // Fs corresponds to sample_rate |
| 104 | Decoder(opus_uint32 sample_rate, int num_channels); |
| 105 | |
| 106 | // Takes a sequence of encoded packets and decodes them. Returns the decoded |
| 107 | // audio. |
| 108 | // see documentation at: |
| 109 | // https://mf4.xiph.org/jenkins/view/opus/job/opus/ws/doc/html/group__opus__decoder.html#ga7d1111f64c36027ddcb81799df9b3fc9 |
| 110 | std::vector<opus_int16> Decode( |
| 111 | const std::vector<std::vector<unsigned char>>& packets, int frame_size, |
| 112 | bool decode_fec); |
| 113 | |
| 114 | int valid() const { return valid_; } |
| 115 | |
| 116 | // Takes an encoded packet and decodes it. Returns the decoded audio |
| 117 | // see documentation at: |
| 118 | // https://mf4.xiph.org/jenkins/view/opus/job/opus/ws/doc/html/group__opus__decoder.html#ga7d1111f64c36027ddcb81799df9b3fc9 |
| 119 | std::vector<opus_int16> Decode(const std::vector<unsigned char>& packet, |
| 120 | int frame_size, bool decode_fec); |
| 121 | |
| 122 | // Generates a dummy frame by passing nullptr to the underlying opus decode. |
| 123 | std::vector<opus_int16> DecodeDummy(int frame_size); |
| 124 | |
| 125 | private: |
| 126 | int num_channels_{}; |
| 127 | bool valid_{}; |
| 128 | internal::opus_uptr<OpusDecoder> decoder_; |
| 129 | }; |
| 130 | |
| 131 | } // namespace opus |
| 132 | |
| 133 | #endif |