| 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 "utils/sum_and_difference_processor.h" |
| 18 | |
| 19 | #include "base/constants_and_types.h" |
| 20 | #include "base/logging.h" |
| 21 | |
| 22 | |
| 23 | namespace vraudio { |
| 24 | |
| 25 | SumAndDifferenceProcessor::SumAndDifferenceProcessor(size_t num_frames) |
| 26 | : temp_buffer_(kNumMonoChannels, num_frames) {} |
| 27 | |
| 28 | void SumAndDifferenceProcessor::Process(AudioBuffer* stereo_buffer) { |
| 29 | |
| 30 | DCHECK_EQ(stereo_buffer->num_channels(), kNumStereoChannels); |
| 31 | AudioBuffer::Channel* temp_channel = &temp_buffer_[0]; |
| 32 | // channel_1' = channel_1 + channel_2; |
| 33 | // channel_2' = channel_1 - channel_2; |
| 34 | *temp_channel = (*stereo_buffer)[0]; |
| 35 | *temp_channel -= (*stereo_buffer)[1]; |
| 36 | (*stereo_buffer)[0] += (*stereo_buffer)[1]; |
| 37 | (*stereo_buffer)[1] = *temp_channel; |
| 38 | } |
| 39 | |
| 40 | } // namespace vraudio |
| 41 |