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/*
Copyright 2018 Google Inc. All Rights Reserved.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS-IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
#include "graph/gain_mixer_node.h"
#include <vector>
#include "base/constants_and_types.h"
namespace vraudio {
GainMixerNode::GainMixerNode(const AttenuationType& attenuation_type,
const SystemSettings& system_settings,
size_t num_channels)
: mute_enabled_(false),
attenuation_type_(attenuation_type),
gain_mixer_(num_channels, system_settings.GetFramesPerBuffer()),
system_settings_(system_settings) {}
void GainMixerNode::SetMute(bool mute_enabled) { mute_enabled_ = mute_enabled; }
bool GainMixerNode::CleanUp() {
CallCleanUpOnInputNodes();
// Prevent node from being disconnected when all sources are removed.
return false;
}
const AudioBuffer* GainMixerNode::AudioProcess(const NodeInput& input) {
if (mute_enabled_) {
// Skip processing and output nullptr audio buffer.
return nullptr;
}
// Apply the gain to each input buffer channel.
gain_mixer_.Reset();
for (auto input_buffer : input.GetInputBuffers()) {
const auto source_parameters =
system_settings_.GetSourceParameters(input_buffer->source_id());
if (source_parameters != nullptr) {
const float target_gain =
source_parameters->attenuations[attenuation_type_];
const size_t num_channels = input_buffer->num_channels();
gain_mixer_.AddInput(*input_buffer,
std::vector<float>(num_channels, target_gain));
}
}
return gain_mixer_.GetOutput();
}
} // namespace vraudio