com.amazonaws.services.iot.demo.danbo.rpi.PiezoBuzzer.java Source code

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Here is the source code for com.amazonaws.services.iot.demo.danbo.rpi.PiezoBuzzer.java

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/** 
 * Copyright 2015 Amazon.com, Inc. or its affiliates. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License"). You may not use 
 * this file except in compliance with the License. A copy of the License is located at
 *
 *     http://aws.amazon.com/apache2.0/
 *
 * or in the "license" file accompanying this file. This file is distributed on an "AS IS"
 * BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the 
 * License for the specific language governing permissions and limitations under the License.
 */

package com.amazonaws.services.iot.demo.danbo.rpi;

import java.util.ArrayList;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 * This class encapsulates the calls to the python script that handles the Piezo
 * Buzzer commands.
 * 
 * @author Fabio Silva (silfabio@amazon.com)
 */
public class PiezoBuzzer implements Runnable {
    private final int OCTAVE_OFFSET = -1;

    int note_pitch[] = { 0, 262, 277, 294, 311, 330, 349, 370, 392, 415, 440, 466, 494, 523, 554, 587, 622, 659,
            698, 740, 784, 831, 880, 932, 988, 1047, 1109, 1175, 1245, 1319, 1397, 1480, 1568, 1661, 1760, 1865,
            1976, 2093, 2217, 2349, 2489, 2637, 2794, 2960, 3136, 3322, 3520, 3729, 3951, 4186, 4435, 4699, 4978 };

    private Log log = LogFactory.getLog(PiezoBuzzer.class);
    private String threadName = "";
    private String tune = "";

    public PiezoBuzzer(String threadName, String tune) {
        this.threadName = threadName;
        this.tune = tune;
    }

    public void run() {
        try {
            log.debug("starting execution of thread: " + threadName);

            log.debug("playing tune: " + tune);
            String[] returnVal = play(tune);
            String command = "sudo python /home/pi/danbo/python/buzzer.py --pitches=" + returnVal[0]
                    + " --durations=" + returnVal[1];
            // call the python script that plays the tune
            log.debug("playing tune with command '" + command + "'");
            Runtime.getRuntime().exec(String.format(command));
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            log.debug("finishing execution of thread: " + threadName);
        }
    }

    public String[] play(String songData) throws Exception {
        ArrayList<Integer> pitches = new ArrayList<Integer>();
        ArrayList<Float> durations = new ArrayList<Float>();

        int default_dur = 4;

        int default_oct = 6;

        int bpm = 63;
        int num;
        long wholenote;
        long duration;
        int note;

        int scale;

        int p = 0;
        while (songData.charAt(p) != ':') {
            p++;
        }
        p++;
        if (songData.charAt(p) == 'd') {
            p++;
            p++;

            num = 0;

            while (Character.isDigit(songData.charAt(p))) {
                num = (num * 10) + Integer.valueOf(songData.charAt(p++) - '0');
            }

            if (num > 0) {
                default_dur = num;
            }

            p++;
        }

        if (songData.charAt(p) == 'o') {
            p++;
            p++;

            num = Integer.valueOf(songData.charAt(p++) - '0');

            if (num >= 3 && num <= 7) {
                default_oct = num;
            }

            p++;
        }

        if (songData.charAt(p) == 'b') {
            p++;
            p++;

            num = 0;
            while (Character.isDigit(songData.charAt(p))) {
                num = (num * 10) + Integer.valueOf(songData.charAt(p++) - '0');
            }
            bpm = num;

            p++;
        }

        wholenote = (60 * 1000L / bpm) * 4;

        while (p < songData.length()) {
            num = 0;
            while (Character.isDigit(songData.charAt(p))) {
                num = (num * 10) + Integer.valueOf(songData.charAt(p++) - '0');
            }

            if (num != 0) {
                duration = wholenote / num;
            } else {
                duration = wholenote / default_dur;
            }
            note = 0;

            switch (songData.charAt(p)) {
            case 'c':
                note = 1;
                break;
            case 'd':
                note = 3;
                break;
            case 'e':
                note = 5;
                break;
            case 'f':
                note = 6;
                break;
            case 'g':
                note = 8;
                break;
            case 'a':
                note = 10;
                break;
            case 'b':
                note = 12;
                break;
            case 'p':
                note = 0;
            default:
                note = 0;
            }
            p++;

            if (songData.charAt(p) == '#') {
                note++;
                p++;
            }

            if (songData.charAt(p) == '.') {
                duration += duration / 2;
                p++;
            }

            if (Character.isDigit(songData.charAt(p))) {
                scale = Integer.valueOf(songData.charAt(p) - '0');
                p++;
            } else {
                scale = default_oct;
            }

            scale += OCTAVE_OFFSET;

            if (songData.charAt(p) == ',') {
                p++;
            }

            if (note != 0) {
                int n = note_pitch[(scale - 4) * 12 + note];
                pitches.add(new Integer(n));
                durations.add(new Float(duration) / new Float(1000));
            } else {
                pitches.add(new Integer(0));
                durations.add(new Float(duration) / new Float(1000));
            }
        }

        String[] returnVal = new String[2];
        returnVal[0] = pitches.toString().substring(1, pitches.toString().length() - 1).replaceAll(" ", "");
        returnVal[1] = durations.toString().substring(1, durations.toString().length() - 1).replaceAll(" ", "");
        return returnVal;
    }
}