1 /*
2  * Copyright 2015 The Android Open Source Project
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 <unistd.h>
18 #include "FlowGraphNode.h"
19 #include "MultiToMonoConverter.h"
20 
21 using namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph;
22 
MultiToMonoConverter(int32_t inputChannelCount)23 MultiToMonoConverter::MultiToMonoConverter(int32_t inputChannelCount)
24         : input(*this, inputChannelCount)
25         , output(*this, 1) {
26 }
27 
28 MultiToMonoConverter::~MultiToMonoConverter() = default;
29 
onProcess(int32_t numFrames)30 int32_t MultiToMonoConverter::onProcess(int32_t numFrames) {
31     const float *inputBuffer = input.getBuffer();
32     float *outputBuffer = output.getBuffer();
33     int32_t channelCount = input.getSamplesPerFrame();
34     for (int i = 0; i < numFrames; i++) {
35         // read first channel of multi stream, write many
36         *outputBuffer++ = *inputBuffer;
37         inputBuffer += channelCount;
38     }
39     return numFrames;
40 }
41 
42