src/tim/prune/data/AudioClip.java

   1 package tim.prune.data;
   2
   3 import java.io.ByteArrayInputStream;
   4 import java.io.File;
   5 import javax.sound.sampled.AudioFileFormat;
   6 import javax.sound.sampled.AudioSystem;
   7
   8 /**
   9  * Class to represent an audio clip for correlation
  10  */
  11 public class AudioClip extends MediaObject
  12 {
  13         /** length of current audio clip in seconds */
  14         private int _lengthInSeconds = LENGTH_UNKNOWN;
  15
  16         private static final int LENGTH_UNKNOWN = -1;
  17         private static final int LENGTH_NOT_AVAILABLE = -2;
  18
  19         /**
  20          * Constructor
  21          * @param inFile file object
  22          */
  23         public AudioClip(File inFile)
  24         {
  25                 // Timestamp is always just taken from the file modification stamp
  26                 super(inFile, new TimestampUtc(inFile.lastModified()));
  27         }
  28
  29         /**
  30          * Constructor
  31          * @param inData byte array of data
  32          * @param inName name of source file
  33          * @param inUrl url from which it came (or null)
  34          */
  35         public AudioClip(byte[] inData, String inName, String inUrl)
  36         {
  37                 super(inData, inName, inUrl);
  38         }
  39
  40         /**
  41          * @return length of this audio clip in seconds
  42          */
  43         public int getLengthInSeconds()
  44         {
  45                 if (_lengthInSeconds == LENGTH_UNKNOWN)
  46                 {
  47                         try {
  48                                 AudioFileFormat format = null;
  49                                 if (getFile() != null)
  50                                         format = AudioSystem.getAudioFileFormat(getFile());
  51                                 else
  52                                         format = AudioSystem.getAudioFileFormat(new ByteArrayInputStream(_data));
  53                                 _lengthInSeconds = (int) (format.getFrameLength() / format.getFormat().getFrameRate());
  54                         }
  55                         catch (Exception e) {
  56                                 _lengthInSeconds = LENGTH_NOT_AVAILABLE;
  57                         }
  58                 }
  59                 return _lengthInSeconds;
  60         }
  61 }