1/* 2 * Copyright (C) 2011 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 18package android.filterpacks.numeric; 19 20import android.filterfw.core.Filter; 21import android.filterfw.core.FilterContext; 22import android.filterfw.core.Frame; 23import android.filterfw.core.FrameFormat; 24import android.filterfw.core.GenerateFieldPort; 25import android.filterfw.format.ObjectFormat; 26 27import java.lang.Math; 28 29/** 30 * @hide 31 */ 32public class SinWaveFilter extends Filter { 33 34 @GenerateFieldPort(name = "stepSize", hasDefault = true) 35 private float mStepSize = 0.05f; 36 37 private float mValue = 0.0f; 38 39 private FrameFormat mOutputFormat; 40 41 public SinWaveFilter(String name) { 42 super(name); 43 } 44 45 @Override 46 public void setupPorts() { 47 mOutputFormat = ObjectFormat.fromClass(Float.class, FrameFormat.TARGET_SIMPLE); 48 addOutputPort("value", mOutputFormat); 49 } 50 51 @Override 52 public void open(FilterContext env) { 53 mValue = 0.0f; 54 } 55 56 @Override 57 public void process(FilterContext env) { 58 Frame output = env.getFrameManager().newFrame(mOutputFormat); 59 output.setObjectValue(((float)Math.sin(mValue) + 1.0f) / 2.0f); 60 pushOutput("value", output); 61 mValue += mStepSize; 62 output.release(); 63 } 64 65 66} 67