basic audio and video tutorial

This part presents how to play audio and video contents.

Audio and video nodes require a Java ME including JSR135 and MeMo player build with audio and video options.
Supported formats (for audio and video) depend of mobile phone.

Note:
Many MeMoPlayer versions does not support audio and video nodes.
To change the MeMo Player, add following line in your app.properties file.
player.name=OWP
MovieTexture node is not supported by MicroEmulator.
Install the Sun Wireless ToolKit to test video on PC (MPEG video only).

[MovieTexture] can display a video file or a video stream.
[AudioClip] can play an audio file or an audio stream.
They are the same interface:

  MFString url
  SFTime   startTime
  SFTime   stopTime

url field define the file name or the stream url.
startTime field define the start time.
stopTime field define the stop time.

See MovieTexture and AudioClip documentation for more informations.

We use MovieTexture like a ImageTexture.
Rectangle node define the video size on mobile phone.

Group {
  children [
    Shape {
      appearance Appearance {
        texture MovieTexture {
          url "http://myserver/myvideofile.mpg"
        }
      }
      geometry Rectangle { size 160 120 }
    }
  ]
}

We use AudioClip like a ImageTexture... In Shape node without geometry field.

Group {
  children [
    Shape {
      appearance Appearance {
        texture AudioClip {
          url "http://myserver/myaudiofile.mp3"
        }
      }
    }
  ]
}

we can also use a Sound2D node.
Sound2D node replace Shape node and offer control to sound intensity (volume).

Group {
  children [
    Sound2D {
      source AudioClip {
        url "http://myserver/myaudiofile.mp3"
      }
    }
  ]
}

To control media playing, see MediaSensor and MediaControl tutorial.

MeMo Player doesn't support MovieTexture and AudioClip nodes

Error:

     [java] MyCanvas:run exception during scene start: java.lang.NullPointerException
     [java] error MIDlet caught java.lang.NullPointerException
     [java] java.lang.NullPointerException
     [java] 	at memoplayer.Group.start(Unknown Source)
     [java] 	at memoplayer.Scene.start(Unknown Source)
     [java] 	at memoplayer.MyCanvas.play(Unknown Source)
     [java] 	at memoplayer.MyCanvas.run(Unknown Source)
     [java] 	at java.lang.Thread.run(Thread.java:619)
     [java] 	at org.microemu.app.util.MIDletThread.run(MIDletThread.java:99)
     [java] error MIDlet caught java.lang.NullPointerException
     [java] java.lang.NullPointerException
     [java] 	at memoplayer.Group.compose(Unknown Source)
     [java] 	at memoplayer.Scene.innerCompose(Unknown Source)
     [java] 	at memoplayer.Scene.compose(Unknown Source)
     [java] 	at memoplayer.MyCanvas.play(Unknown Source)
     [java] 	at memoplayer.MyCanvas.run(Unknown Source)
     [java] 	at java.lang.Thread.run(Thread.java:619)
     [java] 	at org.microemu.app.util.MIDletThread.run(MIDletThread.java:99)
     [java] Main loop: Exception caught: java.lang.NullPointerException

Solution: Change the MeMoPlayer.
To change the MeMo Player, add following line in your app.properties file.

player.name=OWP