xref: /aosp_15_r20/external/oboe/apps/OboeTester/app/src/main/cpp/flowunits/ExponentialShape.cpp (revision 05767d913155b055644481607e6fa1e35e2fe72c)
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 #include <math.h>
18 
19 #include "ExponentialShape.h"
20 
ExponentialShape()21 ExponentialShape::ExponentialShape()
22         : FlowGraphFilter(1) {
23 }
24 
onProcess(int32_t numFrames)25 int32_t ExponentialShape::onProcess(int32_t numFrames) {
26     float *inputs = input.getBuffer();
27     float *outputs = output.getBuffer();
28 
29     for (int i = 0; i < numFrames; i++) {
30         float normalizedPhase = (inputs[i] * 0.5) + 0.5;
31         outputs[i] = mMinimum * powf(mRatio, normalizedPhase);
32     }
33 
34     return numFrames;
35 }
36