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 OBOE_SINC_RESAMPLER_H
18 #define OBOE_SINC_RESAMPLER_H
19 
20 #include <memory>
21 #include <sys/types.h>
22 #include <unistd.h>
23 #include "MultiChannelResampler.h"
24 
25 namespace resampler {
26 
27 /**
28  * Resampler that can interpolate between coefficients.
29  * This can be used to support arbitrary ratios.
30  */
31 class SincResampler : public MultiChannelResampler {
32 public:
33     explicit SincResampler(const MultiChannelResampler::Builder &builder);
34 
35     virtual ~SincResampler() = default;
36 
37     void readFrame(float *frame) override;
38 
39 protected:
40 
41     std::vector<float> mSingleFrame2; // for interpolation
42     int32_t            mNumRows = 0;
43     double             mPhaseScaler = 1.0;
44 };
45 
46 }
47 #endif //OBOE_SINC_RESAMPLER_H
48