| 1 | /* | 
| 2 | Copyright 2018 Google Inc. All Rights Reserved. | 
| 3 |  | 
| 4 | Licensed under the Apache License, Version 2.0 (the "License"); | 
| 5 | you may not use this file except in compliance with the License. | 
| 6 | You may obtain a copy of the License at | 
| 7 |  | 
| 8 |     http://www.apache.org/licenses/LICENSE-2.0 | 
| 9 |  | 
| 10 | Unless required by applicable law or agreed to in writing, software | 
| 11 | distributed under the License is distributed on an "AS-IS" BASIS, | 
| 12 | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | 
| 13 | See the License for the specific language governing permissions and | 
| 14 | limitations under the License. | 
| 15 | */ | 
| 16 |  | 
| 17 | #include "graph/reflections_node.h" | 
| 18 |  | 
| 19 | #include "base/constants_and_types.h" | 
| 20 | #include "base/logging.h" | 
| 21 | #include "base/misc_math.h" | 
| 22 |  | 
| 23 |  | 
| 24 | namespace vraudio { | 
| 25 |  | 
| 26 | ReflectionsNode::ReflectionsNode(const SystemSettings& system_settings) | 
| 27 |     : system_settings_(system_settings), | 
| 28 |       reflections_processor_(system_settings_.GetSampleRateHz(), | 
| 29 |                              system_settings_.GetFramesPerBuffer()), | 
| 30 |       num_frames_processed_on_empty_input_( | 
| 31 |           system_settings_.GetFramesPerBuffer()), | 
| 32 |       output_buffer_(kNumFirstOrderAmbisonicChannels, | 
| 33 |                      system_settings_.GetFramesPerBuffer()), | 
| 34 |       silence_mono_buffer_(kNumMonoChannels, | 
| 35 |                            system_settings_.GetFramesPerBuffer()) { | 
| 36 |   silence_mono_buffer_.Clear(); | 
| 37 |   EnableProcessOnEmptyInput(enable: true); | 
| 38 | } | 
| 39 |  | 
| 40 | void ReflectionsNode::Update() { | 
| 41 |  | 
| 42 |   const auto& current_reflection_properties = reflection_properties_; | 
| 43 |   const auto& new_reflection_properties = | 
| 44 |       system_settings_.GetReflectionProperties(); | 
| 45 |   const bool room_position_changed = | 
| 46 |       !EqualSafe(lhs_begin: std::begin(arr: current_reflection_properties.room_position), | 
| 47 |                  lhs_end: std::end(arr: current_reflection_properties.room_position), | 
| 48 |                  rhs_begin: std::begin(arr: new_reflection_properties.room_position), | 
| 49 |                  rhs_end: std::end(arr: new_reflection_properties.room_position)); | 
| 50 |   const bool room_rotation_changed = | 
| 51 |       !EqualSafe(lhs_begin: std::begin(arr: current_reflection_properties.room_rotation), | 
| 52 |                  lhs_end: std::end(arr: current_reflection_properties.room_rotation), | 
| 53 |                  rhs_begin: std::begin(arr: new_reflection_properties.room_rotation), | 
| 54 |                  rhs_end: std::end(arr: new_reflection_properties.room_rotation)); | 
| 55 |   const bool room_dimensions_changed = | 
| 56 |       !EqualSafe(lhs_begin: std::begin(arr: current_reflection_properties.room_dimensions), | 
| 57 |                  lhs_end: std::end(arr: current_reflection_properties.room_dimensions), | 
| 58 |                  rhs_begin: std::begin(arr: new_reflection_properties.room_dimensions), | 
| 59 |                  rhs_end: std::end(arr: new_reflection_properties.room_dimensions)); | 
| 60 |   const bool cutoff_frequency_changed = | 
| 61 |       current_reflection_properties.cutoff_frequency != | 
| 62 |       new_reflection_properties.cutoff_frequency; | 
| 63 |   const bool coefficients_changed = | 
| 64 |       !EqualSafe(lhs_begin: std::begin(arr: current_reflection_properties.coefficients), | 
| 65 |                  lhs_end: std::end(arr: current_reflection_properties.coefficients), | 
| 66 |                  rhs_begin: std::begin(arr: new_reflection_properties.coefficients), | 
| 67 |                  rhs_end: std::end(arr: new_reflection_properties.coefficients)); | 
| 68 |   const auto& current_listener_position = listener_position_; | 
| 69 |   const auto& new_listener_position = system_settings_.GetHeadPosition(); | 
| 70 |   const bool listener_position_changed = | 
| 71 |       current_listener_position != new_listener_position; | 
| 72 |   if (room_position_changed || room_rotation_changed || | 
| 73 |       room_dimensions_changed || cutoff_frequency_changed || | 
| 74 |       coefficients_changed || listener_position_changed) { | 
| 75 |     // Update reflections processor if necessary. | 
| 76 |     reflection_properties_ = new_reflection_properties; | 
| 77 |     listener_position_ = new_listener_position; | 
| 78 |     reflections_processor_.Update(reflection_properties: reflection_properties_, listener_position: listener_position_); | 
| 79 |   } | 
| 80 | } | 
| 81 |  | 
| 82 | const AudioBuffer* ReflectionsNode::AudioProcess(const NodeInput& input) { | 
| 83 |  | 
| 84 |   const AudioBuffer* input_buffer = input.GetSingleInput(); | 
| 85 |   const size_t num_frames = system_settings_.GetFramesPerBuffer(); | 
| 86 |   if (input_buffer == nullptr) { | 
| 87 |     // If we have no input, generate a silent input buffer until the node states | 
| 88 |     // are cleared. | 
| 89 |     if (num_frames_processed_on_empty_input_ < | 
| 90 |         reflections_processor_.num_frames_to_process_on_empty_input()) { | 
| 91 |       num_frames_processed_on_empty_input_ += num_frames; | 
| 92 |       input_buffer = &silence_mono_buffer_; | 
| 93 |     } else { | 
| 94 |       // Skip processing entirely when the states are fully cleared. | 
| 95 |       return nullptr; | 
| 96 |     } | 
| 97 |   } else { | 
| 98 |     num_frames_processed_on_empty_input_ = 0; | 
| 99 |     DCHECK_EQ(input_buffer->num_channels(), kNumMonoChannels); | 
| 100 |   } | 
| 101 |   output_buffer_.Clear(); | 
| 102 |   reflections_processor_.Process(input: *input_buffer, output: &output_buffer_); | 
| 103 |  | 
| 104 |   // Rotate the reflections with respect to listener's orientation. | 
| 105 |   const WorldRotation inverse_head_rotation = | 
| 106 |       system_settings_.GetHeadRotation().conjugate(); | 
| 107 |   foa_rotator_.Process(target_rotation: inverse_head_rotation, input: output_buffer_, output: &output_buffer_); | 
| 108 |  | 
| 109 |   // Copy buffer parameters. | 
| 110 |   return &output_buffer_; | 
| 111 | } | 
| 112 |  | 
| 113 | }  // namespace vraudio | 
| 114 |  |