DocumentationAnalyticsStreaming media services guide

Buffer start

Last update: June 8, 2026

CREATED FOR:

  • Developer

The buffer start event signals that the media player entered a buffering state.

NOTE
XDM-based APIs (Web SDK, Roku, Media Edge API, Media Collection API): There is no buffer resume event type; buffer end is inferred when you send a play event after bufferStart.
Mobile SDK: Call trackEvent(BufferComplete) when the player exits buffering, then call trackPlay() to resume playback.
Web SDK

Call sendEvent with eventType: "media.bufferStart":

code language-javascript 
alloy("sendEvent", {
  xdm: {
    eventType: "media.bufferStart",
    mediaCollection: {
      sessionID: "{sid}",
      playhead: 45
    }
  }
});
iOS

Call trackEvent with BufferStart when the player enters a buffering state, and BufferComplete when it exits.

code language-swift 
// Buffer starts
tracker.trackEvent(event: MediaEvent.BufferStart, info: nil, metadata: nil)

// Buffer ends
tracker.trackEvent(event: MediaEvent.BufferComplete, info: nil, metadata: nil)
Android

Call trackEvent with BufferStart when the player enters a buffering state, and BufferComplete when it exits.

code language-kotlin 
// Buffer starts
tracker.trackEvent(Media.Event.BufferStart, null, null)

// Buffer ends
tracker.trackEvent(Media.Event.BufferComplete, null, null)
Roku Edge

Call sendMediaEvent with eventType: "media.bufferStart":

code language-brightscript 
m.aepSdk.sendMediaEvent({
    "xdm": {
        "eventType": "media.bufferStart",
        "mediaCollection": {
            "playhead": 45
        }
    }
})
Media Edge API

Call the bufferStart endpoint:

code language-sh 
curl -X POST "https://edge.adobedc.net/ee/va/v1/bufferStart?configId={datastreamID}" \
--header 'Content-Type: application/json' \
--data '{
  "events": [{
    "xdm": {
      "eventType": "media.bufferStart",
      "mediaCollection": {
        "sessionID": "{sid}",
        "playhead": 45
      },
      "timestamp": "YYYY-08-20T22:41:40+00:00"
    }
  }]
}'

Legacy implementation types (Analytics-only)

Media SDK JS 3.x

Call trackEvent with the BufferStart event type:

code language-javascript 
tracker.trackEvent(ADB.Media.Event.BufferStart, null, null);
Chromecast

Call trackEvent with BufferStart when the player enters a buffering state, and BufferComplete when it exits:

code language-javascript 
// Buffer starts
ADBMobile.media.trackEvent(ADBMobile.media.Event.BufferStart);

// Buffer ends
ADBMobile.media.trackEvent(ADBMobile.media.Event.BufferComplete);
Roku 2.x

Call mediaTrackEvent with MEDIA_BUFFER_START when the player enters a buffering state, and MEDIA_BUFFER_COMPLETE when it exits:

code language-brightscript 
adb = ADBMobile()

' Buffer starts
adb.mediaTrackEvent(adb.MEDIA_BUFFER_START)

' Buffer ends
adb.mediaTrackEvent(adb.MEDIA_BUFFER_COMPLETE)
Media Collection API

Send a bufferStart POST to the events endpoint:

code language-json 
{
  "playerTime": { "playhead": 45, "ts": 1699523820000 },
  "eventType": "bufferStart"
}
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