Object Reference > Palette Objects

Tutorial video about the Multimedia Player

Download this project to see a basic implementation of the Multimedia Player in a project.

The multimedia player is a complex object which contains other basic objects. Each basic object is registered in the player itself and takes a special function. The player represents a predefined construction kit which is fully customizable.

A media player can be placed on a frame and is used for playing audio or video files. As many other objects, the multimedia player has a lot of common properties. See here for a description. Only multimedia player specific properties will be described on this page.

Hint: The Multimedia Player object is only available for device panels with audio capabilities. Otherwise you won't see this object in the palette.

Please note:

If you want to use the MP4 formats in your project it is necessary that you purchase a license at https://www.mpegla.com/.

MP3 seems to be free of licenses as of now: https://www.iis.fraunhofer.de/en/ff/amm/consumer-electronics/mp3.html.

For MP4 you need to license “MPEG-4 Visual (Part 2)” and “AVC/H.264 (MPEG-4 Part 10)” in order to use both formats. If you only want to playback MP4 video files the H.264 license should be enough.

If in doubt, please contact the companies and ask for license assistance.

images/mplayer_full2.png

	Name	Type	Events / Actions	Description
1	Play	Button	OnPress Set Media Player Command Command: play Value: Value Not Set OnRelease Set Media Player Command Command: pause Value: Value Not Set	If the "play" command is executed, the current media file will be played. The media time string field (14) and position bargraph (7) will be updated with the current playback time. If no media is set or if there is a playback error, the play button will automatically set to the released state again. If the "pause" command is executed while playback is in progress, the playback will be paused. Executing the pause command while the playback is paused or stopped will have no effect. The button includes two picture graphics for showing play or pause graphics depending on the pressed state.
2	Stop	Button	OnRelease Set Media Player Command Command: stop Value: Value Not Set	Executing the "stop" command while playback is in progress will stop the playback. The value of the media time string field (14) will be set to “00:00 / <totalTime>” and the position bargraph's (7) current value will be set to 0. The play button will automatically be set to the released state. If the stop command is executed while no playback is in progress, it will have no effect.
3	Previous	Button	OnRelease Set Media Player Command Command: previous Value: Value Not Set	When the "previous" command is executed, the media file before the current file in the playlist (17) will be selected. If the current file is the first file in the playlist, pressing the previous button will have no effect.
4	Next	Button	OnRelease Set Media Player Command Command: next Value: Value Not Set	When the "next" command is executed, the media file after the current file in the playlist (17) will be selected. If the current file is the last file in the playlist, pressing the next button will have no effect.
5	Position Decrease	Button	OnRelease Set Media Player Command Command: set position Value: -10	By executing the "set position" command without a value, the current value of the position bargraph (7) is used to set the playback position of the current file. If a value is provided, this value is used as an offset to set the current position as long as it is not longer than the total length of the current media file.
6	Position Increase	Button	OnRelease Set Media Player Command Command: set position Value: +10
7	Position Bar	Linear Bargraph	OnValueChange Set Media Player Command Command: set position Value: Value Not Set
8	Shuffle	Button	OnPress Set Media Player Command Command: shuffle Value: Value Not Set OnRelease Set Media Player Command Command: shuffle Value: Value Not Set	If the "shuffle" command is executed, the playlist order will be randomized. If the media player is in play state, the current selected file shall be still continued. The button includes two picture graphics for showing shuffle or not shuffle graphics depending on the pressed state.
9	Loop	List	OnValueChange Set Media Player Command Command: loop Value: Value Not Set	By executing the "loop" command, the next loop mode will be applied. The inital loop mode is 2. This list shall have three picture graphics as children. Each represents a different loop mode: At value 0: Loop off (image shows a not-closed ellipse) At value 1: Loop current file (image shows ellipse with two arrow heads) At value 2: Loop all (when end of playlist was reached, jump to start of playlist) (image shows ellipse with one arrow head)
10	Volume Decrease	Button	OnRelease Set Media Player Command Command: set volume Value: -10	When executing the "set volume" command without a value, the current value of the volume bargraph (12) is used to set the volume of the current playback. If a value is provided, this value is used to set the volume of the current playback. The volume bargraph will then be updated with the set value. The volume settings will also work if currently no media file is selected, they will be applied as soon as a media file is set. The volume settings are applied to all media files of this multimedia player and are not specific to one certain file.
11	Volume Increase	Button	OnRelease Set Media Player Command Command: set volume Value: +10
12	Volume Bar	Linear Bargraph	OnValueChange Set Media Player Command Command: set volume Value: Value Not Set
13	Volume ON/OFF	Button	OnPress Set Media Player Command Command: mute Value: Value Not Set OnRelease Set Media Player Command Command: unmute Value: Value Not Set	When executing the "mute" command, the volume of the currently played back media file is internally set to 0. The value of the volume bargraph (12) will not be changed and remains the same. When executing the "unmute" command, the current volume of the volume bargraph (12) is used to set the volume of the currently played back media file. The button includes two picture graphics for showing mute or unmute graphics depending on the pressed state.
14	Media Time	String Field		This information string field shows the current time of the playback and the total time of the media file (e.g. “00:42 / 03:14”)
15	Media Title	String Field		The Field shows the current played or paused media file
16	Display	Container		The display is an content area which showing the video or the album art of the audio file. (If not available, nothing is shown here).
17	Playlist	Table		The playlist shows the currently selected media files at run and design time. Hints: At design time there are no scrollbars visible. At runtime you can scroll the playlist by changing its "Preview Value" or via encoder after enabling the "Set As Input" property.

The graphic below shows the default property states of the multimedia player object.

Fit To Frame Size

Enable this property to adapt the size of the multimedia player to the parent frame object.

Default value: Disabled

Possible values:

•Disabled: The Multimedia Player can be dynamically scaled to the desired size.

•Enabled: The Multimedia Player will be scaled to the parent frame size.

Auto Rearrange Controls

This property activates / deactivates the internal layout manager of the multimedia player object. The manager takes

care about the positioning and sizing of all included objects in design time. The layout manager has no effect at runtime.

Resizing is only done when the object size is changed.

Default value: Enabled

Possible values:

•Disabled: The Multimedia Player objects will not be sized and positioned when changing the size of the Multimedia Player object.

•Enabled: The Multimedia Player objects will be sized and positioned automatically when changing the size of the Multimedia Player object.

Show Display

This feature removes the display container to use the multimedia player as a pure audio player or as a playback control bar:

Default value: Enabled

Possible values:

•Disabled: Removes the display container.

•Enabled: Adds a display container.

Show Playlist

The playlist shows the currently selected media files at runtime and design time. But in the latter case without scrollbars.

Default value: Disabled

Possible values:

•Disabled: Removes the playlist table.

•Enabled: Add a new playlist table.

Show Backward / Forward Buttons

If the target device has no encoder to set the media position by using the position bar, this property can be enabled

to add a backward and a forward button to the multimedia player. With these buttons the media position can be increased or decreased

Default value: Disabled

Possible values:

•Disabled: Removes the backward / forward buttons from the multimedia player.

•Enabled: Adds the backward / forward buttons to the multimedia player.

Show Volume Bar Buttons

If the target device has no encoder to set the volume by using the volume bar, this property can be enabled to add a volume increase and decrease button to the multimedia player. With these buttons the volume value can be increased or decreased

Default value: Disabled

Possible values:

•Disabled: Removes the volume increase / decrease buttons).

•Enabled: Add's the volume increase / decrease buttons.

Full Path In Title

This property shows the full path of the played media file in the title string field at runtime instead of only the file name.

Default value: Disabled

Possible values:

•Disabled: The media title stringfield shows only the filename

•Enabled: The media title stringfield shows the full path of the played media file.

Playlist Media Files

By clicking on this property, a media file chooser dialog will be displayed. Here the user can modify his playlist.

This dialog supports the following operations: “Add” (1), “Remove” (2), “Up” (3) (playlist position), “Down” (4) (playlist position).

Default value: empty

Possible values: Multiple media files in the supported formats (mp3, mp4, mka, mkv, mp4, oga, ogg, ogv, wav, wma, wmv).

See the FAQ section below about codec information

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Playlist Width

This value adjusts the width of the playlist if it is shown. The state of this property is depending on the value of the “Show Playlist” property.

Default value: Disabled

Possible values: 1 ... width of the multimedia player object - 2 x (default component gap = 2 + border width) -1

What video and audio codecs are supported?

Video

The following video codecs have been verified on the device:

•H264 - MPEG-4 AVC (part 10) (avc1)

•MPEG-1/2 Video (mpgv)

•Motion JPEG Video (MJPG)

•Google/On2's VP8 Video (VP80)

The following video codecs are currently NOT SUPPORTED on the device:

•Theora Video

•MPEG-4 Video (DX50) => DIVX version 5

•Any Windows media format in an AFS container (VC1, WMV)

Audio

The following audio codecs have been verified on the device:

•MPEG Audio layer 1/2/3 (mpga)

•Vorbis Audio (vorb)

•Raw wave files in different format (tested: PCM S16 LE (araw), PCM U8 (araw))

Why should VLC be installed?

For using the multimedia player object it is NOT neccessary that VLC is installed on your PC but it can help in the following topics:

•Check what codecs are used by specific media file

•Convert (transcode) a media file to a supported codec

VLC can be downloaded here. It is open source software and can be installed without charge (please consider a donation :) ).

What is the suggested video and audio codec and how to convert my video?

We suggest to use .mp4 files with "H264 - MPEG-4 AVC (part 10) (avc1)" as video codec and "MPEG AAC Audio (mp4a)" as audio codec.

To convert to a supported codec, VLC (see above) can be used. Here is a short manual.

What is the difference between the multimedia playback on Windows simulation and on the device

The frontend for playing back media files with the MultimediaPlayer object is the same on both platforms. However, the backend is completely different. On the Windows PC the simulation uses the capabilities of the operating system and the installed software codecs. On the device the hardware decoding functions of the CPU are directly used to minimize CPU load.

Because of this difference, the playback can be different on both platforms. One of the biggest differences can be that a media file that can be played back in the simulation on the Windows PC cannot be played back on the device. This can happen if a codec is installed on the PC but is not supported by the CPU on the device. Other differences that may appear are different timings when executing a multimedia action or (e.g. when going to the next file in the playlist the total time of the next file might appear faster on one platform than on the other).

We strongly recommend that testing is not only done with the Windows simulation but also directly on the device!

Why is my media file not playing in the Windows simulation?

There might be a codec missing. The K-Lite Codec Pack supports all the codecs supported on the device (and many more). After installing this codec pack, restart the simulation and try again.

Download it here (the basic version should be enough).

Do I need to be concerned about performance when playing video or audio?

Yes and no. When using one of the supported codecs above, the built in hardware acceleration is used on the device to minimize CPU load (while playback the CPU load increses between 3% and 7% on a single core CPU).

BUT there are some things to keep in mind: When running on a single core CPU it is more likely that playback of multimedia has an influence on the system. Especially tight CAN timings may be a problem (e.g. sending out a CAN message every 10ms might not be completely precise anymore). We strongly recommend that the project is tested on the device while playing back media with a special look at CAN (send and receive) and script timings.

When running on a device with a dual or quad core CPU it is less likely that media playback has a negative influence on the overall performance.

What happens when the page is changed while playback?

It depends on what kind of media is played back:

If a video is played back when exiting the page with the multimedia player, the playback will be stopped automatically.

If only audio (music) is played back when exiting the page with the multimedia player, the playback will continue. If the audio playback shall be stopped when the page is switched, you have to stop the media player manually (e.g. via a multimediaCommand JavaScript call onPageExit).

Why is the volume so low?

Please have a look at the volume FAQ section.

How can I control playback in JavaScript?

Use the multimediaCommand function in JavaScript to control the multimedia player and it's playlist.

How can I switch the video to fullscreen and how to exit fullscreen mode?

Use the multimediaCommand function in JavaScript with the command string "toggle fullscreen" to enable or disable fullscreen video. Fullscreen mode is automatically disabled again as soon as the user touches the screen or presses the escape key.

How can the display operator play his own media files?

It is possible to add media files that are stored on an USB device to the playlist of the MultimediPlayer. To do this JavaScript needs to be used. Here is an example script that adds all files from the folder "music" on an usb stick to the playlist:

//check if USB stick is inserted:

var usbInserted = getVariableValue("@USBMemStatus");

if (usbInserted != 0)

{

//USB stick present, get the mount path

var usbPath = getVariableValue("@USBMountPath");

//add "music" folder to the usb path

usbPath = usbPath + "/music";

//remove all files from playlist

multimediaCommand(34, "clear playlist");

//now add all files from the music directory to the playlist

multimediaCommand(34, "add directory to playlist", usbPath);

}

else

{

//no usb stick present, show alarm 1 that shows an eror message

setVariableValue("@AlarmShow", 0x8001);

}

Why can't I change the position in an MP3 file?

Changing position (seeking) for MP3 encoded audio files is currently not supported by the backend. If seeking is importand, the MP3 files can be converted to e.g. MPEG AAC or Vorbis audio files.