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Version: 4.0.1

Random playback

The SMIL player offers functionality to specify a play mode for a specific playlist in the player's XML definition file. This feature is useful when you want to play content in a random order or randomly pick one element from the specified playlist.

Play modes​

SMIL player supports three types of play modes:

  • random - In every time player reaches segment, the SMIL player shuffles the playlist and plays the whole playlist in a random order.

  • random_one - In every time player reaches segment, the SMIL player randomly picks one element from the playlist and plays only that element.

  • one - In every time player reaches segment, the SMIL player plays only one element from the playlist. In the next playback cycle, the SMIL player will pick the element that comes directly after the previous one. This behavior continues until the end of the playlist, after which it will start again from the beginning.

The value is case-insensitive; an unknown value plays the whole playlist in normal order.

Playlist definition​

Play mode is specified in the playMode attribute of the seq element. The children may be plain media elements, or <seq>/<par> groups when one "element" should consist of several media played together — with one and random_one, each child group counts as a single pick:


<seq playMode="one">
    <seq>
        <video src="https://static.signageos.io/assets/video-test-1_e07fc21a7a72e3d33478243bd75d7743.mp4"
               region="main"/>
    </seq>
    <seq>
        <img dur="3s"
             src="https://demo.signageos.io/smil/samples/assets/landscape1.jpg"
             region="main" fit="fill"/>
        <img dur="3s"
             src="https://demo.signageos.io/smil/samples/assets/landscape2.jpg"
             region="main" fit="fill"/>
    </seq>
    <seq>
        <img src="https://demo.signageos.io/smil/zones/files/img_1.jpg"
             dur="3s" region="main"/>
    </seq>
</seq>

<seq playMode="random">
    <video src="https://static.signageos.io/assets/video-test-1_e07fc21a7a72e3d33478243bd75d7743.mp4"
           region="main"/>
    <img dur="3s"
         src="https://demo.signageos.io/smil/samples/assets/landscape1.jpg"
         region="main" fit="fill"/>
    <img dur="3s"
         src="https://demo.signageos.io/smil/samples/assets/landscape2.jpg"
         region="main" fit="fill"/>
</seq>

Limitation of playMode="random": shuffling works on playlists whose children are plain media elements (as in the example above). Nested <seq>/<par> children are not reshuffled — they play in their defined order. Use random_one (which fully supports nested children) if you need random selection of grouped content.

Synchronized playback​

playMode="one" works together with multi-device synchronization: in a synced region, the coordination master broadcasts which element it picked, and the other devices play the same one — so randomised playlists stay identical across the whole sync group.