source: trunk/src_apollo/org/apollo/util/AudioMath.java@ 315

package org.apollo.util;

import javax.sound.sampled.AudioFormat;

/**
 * Misc audio routines.
 * 
 * @author Brook Novak
 *
 */
public class AudioMath {
        private AudioMath() {}
    
        public static float volToDb(float volume) {
                return (float) (Math.log(volume==0.0 ? 0.0001 : volume) / Math.log(10.0) * 20.0);
        }

        public static float dBToVol(float dB) {
                return (float) Math.pow(10.0, dB / 20.0);
        }
        
        /**
         * 
         * @param ms
         * @param format
         * @return How many frames are in the given ms time
         */
        public static int millisecondsToFrames(long ms, AudioFormat format) {
                double portion = ms;
                portion /= 1000.0;
                return (int)(format.getFrameRate() * portion);
        }
        
        public static long framesToMilliseconds(long frames, AudioFormat format) {
                double portion = frames;
                portion /= (double)format.getFrameRate();
                return (long)(portion * 1000.0);
        }
        
        public static int framesToSeconds(long frames, AudioFormat format) {
                return (int)(frames / format.getFrameRate());
        }
}