1 /* 2 * Copyright 2019 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 #ifndef FLOWGRAPH_SAMPLE_RATE_CONVERTER_H 18 #define FLOWGRAPH_SAMPLE_RATE_CONVERTER_H 19 20 #include <unistd.h> 21 #include <sys/types.h> 22 23 #include "FlowGraphNode.h" 24 #include "resampler/MultiChannelResampler.h" 25 26 namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph { 27 28 class SampleRateConverter : public FlowGraphFilter { 29 public: 30 explicit SampleRateConverter(int32_t channelCount, 31 resampler::MultiChannelResampler &mResampler); 32 33 virtual ~SampleRateConverter() = default; 34 35 int32_t onProcess(int32_t numFrames) override; 36 getName()37 const char *getName() override { 38 return "SampleRateConverter"; 39 } 40 41 void reset() override; 42 43 private: 44 45 // Return true if there is a sample available. 46 bool isInputAvailable(); 47 48 // This assumes data is available. Only call after calling isInputAvailable(). 49 const float *getNextInputFrame(); 50 51 resampler::MultiChannelResampler &mResampler; 52 53 int32_t mInputCursor = 0; // offset into the input port buffer 54 int32_t mNumValidInputFrames = 0; // number of valid frames currently in the input port buffer 55 // We need our own callCount for upstream calls because calls occur at a different rate. 56 // This means we cannot have cyclic graphs or merges that contain an SRC. 57 int64_t mInputCallCount = kInitialCallCount; 58 59 }; 60 61 } /* namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph */ 62 63 #endif //FLOWGRAPH_SAMPLE_RATE_CONVERTER_H 64