MMADemo Application and MediaControlSkin

Java™ 2 Platform, Micro Edition, Wireless Toolkit
Version 2.1

December 2003

About the mmademo and the MediaControlSkin

Of the multimedia demo applications provided, the Simple Player and Video applications demonstrate the full extent of the MMAPI features. This appendix describes these two demo applications and the MediaControlSkin provided by the J2ME^TM Wireless Toolkit that contains audio and playback controls to use on the mmademo demo programs.

Simple Player

The SimplePlayer demo application demonstrates the range of audio and video capabilities of the MMAPI. Simple Player consists of an HTTP and Record Management System (RMS) directory browser, a player, and a customized ring tone parser.

The HTTP browser lets you browse HTTP directories. To make SimplePlayer's browser treat the URL as a directory, you need to include a slash at the end of the URL address. Selecting a media file opens it in SimplePlayer. You can also download HTTP files and save them to an storage directory of your choosing.

The player portion uses a generic javax.microedition.media.Player interface. The player displays duration, media time, and controls for running the media file. If metadata is available in a file, the player enables you to view the information, such as author and title. In the case of MIDI files, if karaoke text is present in the file, it displays on the screen during play. Graphical user interface controls can be viewed on the display screen if applicable. You can access these controls, by selecting one of the media samples in SimplePlayer, then pressing the Menu button to view and select the desired command.

In addition, SimplePlayer parses ring tones in Ringing Tones text transfer language (RTTTL). See http://www.convertyourtone.com/rtttl.html for information on RTTTL.

For a list of MMAPI-specific audio and video controls available on the emulator's keypad, see TABLE 4.

The demo includes the following media samples:

Bong. Plays a short WAV file. You can adjust certain playback features, for a list of features, see TABLE 1. The display shows the duration of the tone in minutes:seconds:tenths of a second, for example 00:17:5. This WAV file is accessed from a JAR file.
MIDI Scale. Plays two renditions of the musical scale, first rendition is a series of tones and the second is a series of synthetic tones. The display shows the title of the music selection, the duration of the audio, the elapsed time during execution, and the bpm of execution. By pressing the left or right selection arrows during playback, you can alter the pitch. This MIDI file is accessed from a JAR file.
Simple Ring Tone. Plays a short sequence of Beethoven's Ninth Symphony. The display shows the title of the music selection, the duration of the audio, the elapsed time in seconds and fractions of a second during execution, and the beats per minute (bpm) of execution. By pressing the left or right selection arrows during playback, you can alter the pitch. This MIDI file is accessed from a JAR file.
JavaONE Theme. Plays a brief audio file. The display shows the title of the music selection, the duration of the audio the elapsed time during execution, and the bpm of execution. This WAV file is accessed from an HTTP site. This application requires an internet connection.
MIDI Scale. Same as the previous MIDI Scale demo, however, the audio file is accessed from an HTTP site. This application requires an internet connection.
Sun Behind Video. Shows a short video. The application demonstrates video controls and playback features. This application requires an internet connection.
Browse RMS. Lets you select and play a previously saved audio or video file from an RMS directory.
Audio Capture from a default device. Lets you capture audio from a radio or other device. The sound is captured and played back, so you hear the initial sound followed by the playback of the sound after a brief latency.
[enter URL]. Plays back audio and video files from the Internet. Type a valid URL at the insertion point and click OK to play a WAV, MIDI, or MPEG-1 file. This application requires an internet connection. If opening an HTTP directory from which to select a media, be sure to add a slash to the end of the URL address.

A key feature of SimplePlayer is the implementation of keypad functions for non-video media. The following table shows which controls are available in the SimplePlay for various media types (WAV, MIDI, or MPEG-1 files).

Go to http://java.sun.com/products/mmapi/index.html to see how these controls are implemented by examining the classes associated with the controls in the Mobile Media API.

TABLE 1. Audio and Video Controls for SimplePlayer Applications

Keypad Commands Video WAV
PCM MIDI/
Ring Tone Class

Mute/Unmute Sometimes Always Always VolumeControl

Volume Sometimes Always Always VolumeControl

META data Sometimes Sometimes Sometimes MetaDataControl

Stop in 5 seconds Always Always Always StopTimeControl/td>

Rate Always Never Always RateControl

Tempo Never Never Always TempoControl

Pitch Never Never Always PitchControl

Start/Stop Recording Never Always Never RecordControl

Full Screen Always Never Never VideoControl

Frame Forward/Backward Always Never Never FramePositioningControl

Play/Stop Always Always Always Player

Loopmode Always Always Always Player

Skip Forward/Backward Always Always Always Player

Rewind Always Always Always Player

TABLE 1. Audio and Video Controls for SimplePlayer Applications
Keypad Commands	Video	WAV PCM	MIDI/ Ring Tone	Class
Mute/Unmute	Sometimes	Always	Always	VolumeControl
Volume	Sometimes	Always	Always	VolumeControl
META data	Sometimes	Sometimes	Sometimes	MetaDataControl
Stop in 5 seconds	Always	Always	Always	StopTimeControl/td>
Rate	Always	Never	Always	RateControl
Tempo	Never	Never	Always	TempoControl
Pitch	Never	Never	Always	PitchControl
Start/Stop Recording	Never	Always	Never	RecordControl
Full Screen	Always	Never	Never	VideoControl
Frame Forward/Backward	Always	Never	Never	FramePositioningControl
Play/Stop	Always	Always	Always	Player
Loopmode	Always	Always	Always	Player
Skip Forward/Backward	Always	Always	Always	Player
Rewind	Always	Always	Always	Player

The following table defines the menu commands available with the SimplePlayer demo:

TABLE 2. SimplePlayer Menu Commands
Commands	Definitions
Mute	Turns off sound but the file continues to execute. This command toggles to Unmute.
Volume	Increases or decreases loudness.
META Data	Displays information provided by the media file such as, copyright information, the title of the audio piece, and a track list.
Stop in 5 seconds	Pauses the audio play in five seconds when set during execution.
Rate	Alters the rate of speed of playback.
Tempo	Increases or decreases the tempo of the tone sequence or MIDI file.
Pitch	Lowers or raises the notes in a MIDI file.
Start/Stop Recording	Records the audio playback. A file is created containing the recorded audio in the directory in which the emulator is running. If you do not specify a filename, a file called `recording.wav` is created. This command toggles to Stop Recording.
Full Screen	Displays a video in the full screen display area.
Frame Forward/Backward	Jumps forward or backward one frame at a time in a video file.
Play/Stop	Starts or stops the program.
Loopmode	Plays back the audio file immediately after completion of play. Running Loopmode once plays the audio file once. Pressing a second time plays the file three times. Pressing a third time plays the file repeatedly. Pressing a fourth time returns to single play.
Skip Forward/Back	Skips forward or backward five percent of the duration of the media file. The sound track syncs to the video.
Rewind	Returns to the start time of the audio playback.

Video

The Video demo application shows a stream of random scenes with background music demonstrating the synchronization of both an audio player and a video player. The Video demo can be viewed in a Form or Canvas. Choosing the Form option runs the video in the screen display area. Choosing the Canvas option runs the video in a canvas in the screen display area. Both versions of the Video demo are accessed through an internet connection. If you are running the Video demo from behind a firewall, remember to set your proxy server and port.

When you choose the Form option, information about the video is shown above the video display. The information given includes the current status of the video (Playing or Paused), the rate of play, the volume level of the audio being played, and the frame position.

Notice that when running the Video demo, one of the soft buttons is labeled Snapshot. Pressing this button while the video is running, captures a frame of the video at the instant the button is pressed. If you are running Video with the Canvas option, the snapshot momentarily replaces the video in the screen display area. If you are running Video with the Form option, the snapshot is placed immediately below the video. Successive snapshots are stacked in order below the first snapshot.

MMAPI Supported Formats

MMAPI supported formats in the J2ME Wirless Toolkit are:

Audio (same for full and Audio Building Block): PCM and WAV audio of all types.
MIDI: Type 0, Type 1 MIDI, and SP-MIDI
Video (full only): MPEG-1
Audio Capture: Audio capture supported formats cannot be queried using the API. Supported parameters depends on the platform and sound card, but typical formats that work on the different platforms are:
- Microsoft Windows 2000 operating environment:
  8000 Hz, 11025 Hz, 22050 Hz, 44100 Hz, and 48000 Hz
  8-bit/Unsigned, 16-bit/Signed/LittleEndian - Other combinations may not work
  Mono and Stereo
- Solaris^TM operating environment:
  8000 Hz, 11025 Hz, 22050 Hz, 44100 Hz, and 48000 Hz
  16-bit/Signed/LittleEndian - Other combinations may not work
  Mono and Stereo
- Linux operating environment:
  8000 Hz, 11025 Hz, 22050 Hz, 44100 Hz, and 48000 Hz
  16-bit/Signed/LittleEndian - Other combinations may not work
  Mono and Stereo

Limitations on Using the MMAPI in the Wireless Toolkit

Only one MIDI or Tone Sequence player can be in use at any time. Creating multiple MIDI and Tone sequence players is possible. But only one MIDI player can be realized. Realizing a second MIDI player or Tone sequence player will get a MediaException.
For Single Tone, any number of simultaneous playTone calls is supported. At least 4 simultaneous playTone calls is guaranteed to work. The playTone calls can be made while a midi or tone sequence player is playing.
The number of video players is limited by the amount of heap size (-heapsize) allocated. Roughly, 4 concurrent http playbacks can be run with 500KB of heap.
The number of WAV audio Players is limited by the amount of heap space allocated. Mixing is supported for up to 10 Players on some machines. In any case, when the limit is reached, prefetching throws a MediaException.
Only one audio capturer can be in use at one time. Connecting a second audio capturer fails with a MediaException.
Supports only up to 4 simultaneous opened HTTP connections (MIDP's limitation).

Attributes for mmademo

The mmademo applications has the following attributes that you can modify in the User Defined panel of the Project Settings dialog box:

TABLE 3. Descriptions of MMAPI-specific MIDlet Attributes
Attribute	Description	Attribute File
`Player`-<n>	Name of the nth media title to be played back by the SimplePlayer MIDlet.	JAD
`PlayerURL`-<n>	Location of the nth media title, `playerTitle`-<n> to be played back by the SimplePlayer MIDlet.	JAD
`VideoTest`-<n>	The name of the nth media title to be played back by the VideoTest MIDlet.	JAD
`VideoTest`>-`URL`<n>	Location of the nth media title, `playerTitle`-<n> to be played back by the VideoTest MIDlet.	JAD

MediaControlSkin

A special skin is provided by the Wireless Toolkit that contains audio and video playback controls that you can use to modify and test the features in the mmademo. Playback control buttons for sound and video are described in the following table:

Table 4. Audio and Video Playback Controls on `MediaControlSkin` Keypad
Keypad Buttons	Function
1/Reverse	Stops video and reverses approximately 10% and resumes play.
2/Play-Pause	Press once to pause video, press again to resume play.
3/Forward	Stops video and advances approximately 10% and resumes play.
4/Slow	Slows play of video incrementally as you hold button down.
5/Stop	Stops video playback.
6/Speed Up	Increase speed of video play incrementally as you hold button down.
7/Go Back	Goes back one frame during play.
8/Full Screen	Toggles to fill entire display area or reduce area of video display. Note that switching screen size modes causes flashing.
9/Go Forward	Advances video one frame during play.
*/Decrease Volume	Lowers audio volume.
0/>Mute	Mutes audio.
#/Increase Volume	Increases audio volume.

Buttons are active relative to the type of application running. For instance, if a .wav file is running, the buttons controlling video are inactive. Similarly, the soft button labels are relative to the type of application running. For instance, if a video is running, the label Snapshot is displayed. Snapshot captures a frame in the video at the instant the button is depressed. Note that buttons implemented for video media might be implemented by a user program such as MediaPlayer.

The MediaControlSkin device, contains the following features:

Tone and Tone Sequencing. Supports single or multiple tones and tone sequencing. If you are creating a MIDlet application that incorporates sound, the MediaControlSkin device can generate tones given the note, duration, and volume that you specify.
MIDI support. Enables you to playback standard MIDI files and provides you with direct control of the MIDI device.
WAV playback. Enables you to control the playback of audio files in WAV format.
WAV recording to file or stream. Enables you to record audio files in WAV format to a specific file or stream.
PCM audio capture and playback. Enables you to capture audio files in PCM format and to control the playback.
MPEG-1 video playback with audio. Enables you to view MPEG-1 videos. The MediaControlSkin emulator's keypad contains keypad buttons for controlling audio and video operations.