# DefaultLivePlaybackSpeedControl

Artifact: [androidx.media3:media3-exoplayer](https://developer.android.com/jetpack/androidx/releases/media3) [View Source](https://cs.android.com/search?q=file:androidx/media3/exoplayer/DefaultLivePlaybackSpeedControl.java+class:androidx.media3.exoplayer.DefaultLivePlaybackSpeedControl)

*** ** * ** ***


```
@UnstableApi
public final class DefaultLivePlaybackSpeedControl implements LivePlaybackSpeedControl
```

<br />

*** ** * ** ***

A `https://developer.android.com/reference/androidx/media3/exoplayer/LivePlaybackSpeedControl` that adjusts the playback speed using a proportional controller.

The control mechanism calculates the adjusted speed as `1.0 + proportionalControlFactor
x (currentLiveOffsetSec - targetLiveOffsetSec)`. Unit speed (1.0f) is used, if the `
currentLiveOffsetSec` is closer to `targetLiveOffsetSec` than the value set with `https://developer.android.com/reference/androidx/media3/exoplayer/DefaultLivePlaybackSpeedControl.Builder#setMaxLiveOffsetErrorMsForUnitSpeed(long)`.

The resulting speed is clamped to a minimum and maximum speed defined by the media, the fallback values set with `https://developer.android.com/reference/androidx/media3/exoplayer/DefaultLivePlaybackSpeedControl.Builder#setFallbackMinPlaybackSpeed(float)` and `https://developer.android.com/reference/androidx/media3/exoplayer/DefaultLivePlaybackSpeedControl.Builder#setFallbackMaxPlaybackSpeed(float)` or the `https://developer.android.com/reference/androidx/media3/exoplayer/DefaultLivePlaybackSpeedControl#DEFAULT_FALLBACK_MIN_PLAYBACK_SPEED()` and `https://developer.android.com/reference/androidx/media3/exoplayer/DefaultLivePlaybackSpeedControl#DEFAULT_FALLBACK_MAX_PLAYBACK_SPEED()` fallback default values.

When the player rebuffers, the target live offset `https://developer.android.com/reference/androidx/media3/exoplayer/DefaultLivePlaybackSpeedControl.Builder#setTargetLiveOffsetIncrementOnRebufferMs(long)` to adjust to the reduced network capabilities. The live playback speed control also `https://developer.android.com/reference/androidx/media3/exoplayer/DefaultLivePlaybackSpeedControl.Builder#setMinPossibleLiveOffsetSmoothingFactor(float)` of the minimum possible live offset to decrease the target live offset again if conditions improve. The minimum possible live offset is derived from the current offset and the duration of buffered media.

## Summary

| ### Nested types |
|---|
| `public final class https://developer.android.com/reference/androidx/media3/exoplayer/DefaultLivePlaybackSpeedControl.Builder` Builder for a `https://developer.android.com/reference/androidx/media3/exoplayer/DefaultLivePlaybackSpeedControl`. |

| ### Constants |
|---|---|
| `static final float` | `https://developer.android.com/reference/androidx/media3/exoplayer/DefaultLivePlaybackSpeedControl#DEFAULT_FALLBACK_MAX_PLAYBACK_SPEED() = 1.03f` The default maximum factor by which playback can be sped up that should be used if no maximum playback speed is defined by the media. |
| `static final float` | `https://developer.android.com/reference/androidx/media3/exoplayer/DefaultLivePlaybackSpeedControl#DEFAULT_FALLBACK_MIN_PLAYBACK_SPEED() = 0.97f` The default minimum factor by which playback can be sped up that should be used if no minimum playback speed is defined by the media. |
| `static final long` | `https://developer.android.com/reference/androidx/media3/exoplayer/DefaultLivePlaybackSpeedControl#DEFAULT_MAX_LIVE_OFFSET_ERROR_MS_FOR_UNIT_SPEED() = 20` The default maximum difference between the current live offset and the target live offset, in milliseconds, for which unit speed (1.0f) is used. |
| `static final float` | `https://developer.android.com/reference/androidx/media3/exoplayer/DefaultLivePlaybackSpeedControl#DEFAULT_MIN_POSSIBLE_LIVE_OFFSET_SMOOTHING_FACTOR() = 0.999f` The default smoothing factor when smoothing the minimum possible live offset that can be achieved during playback. |
| `static final long` | `https://developer.android.com/reference/androidx/media3/exoplayer/DefaultLivePlaybackSpeedControl#DEFAULT_MIN_UPDATE_INTERVAL_MS() = 1000` The default `https://developer.android.com/reference/androidx/media3/exoplayer/DefaultLivePlaybackSpeedControl.Builder#setMinUpdateIntervalMs(long)` between playback speed changes, in milliseconds. |
| `static final float` | `https://developer.android.com/reference/androidx/media3/exoplayer/DefaultLivePlaybackSpeedControl#DEFAULT_PROPORTIONAL_CONTROL_FACTOR() = 0.1f` The default `https://developer.android.com/reference/androidx/media3/exoplayer/DefaultLivePlaybackSpeedControl.Builder#setProportionalControlFactor(float)` used to adjust the playback speed. |
| `static final long` | `https://developer.android.com/reference/androidx/media3/exoplayer/DefaultLivePlaybackSpeedControl#DEFAULT_TARGET_LIVE_OFFSET_INCREMENT_ON_REBUFFER_MS() = 500` The default increment applied to the target live offset each time the player is rebuffering, in milliseconds |

| ### Public methods |
|---|---|
| `float` | `https://developer.android.com/reference/androidx/media3/exoplayer/DefaultLivePlaybackSpeedControl#getAdjustedPlaybackSpeed(long,long)(long liveOffsetUs, long bufferedDurationUs)` Returns the adjusted playback speed in order get closer towards the `https://developer.android.com/reference/androidx/media3/exoplayer/LivePlaybackSpeedControl#getTargetLiveOffsetUs()`. |
| `long` | `https://developer.android.com/reference/androidx/media3/exoplayer/DefaultLivePlaybackSpeedControl#getTargetLiveOffsetUs()()` Returns the current target live offset, in microseconds, or `https://developer.android.com/reference/androidx/media3/common/C#TIME_UNSET()` if no target live offset is defined for the current media. |
| `void` | `https://developer.android.com/reference/androidx/media3/exoplayer/DefaultLivePlaybackSpeedControl#notifyRebuffer()()` Notifies the live playback speed control that a rebuffer occurred. |
| `void` | `https://developer.android.com/reference/androidx/media3/exoplayer/DefaultLivePlaybackSpeedControl#setLiveConfiguration(androidx.media3.common.MediaItem.LiveConfiguration)(https://developer.android.com/reference/androidx/media3/common/MediaItem.LiveConfiguration liveConfiguration)` Sets the live configuration defined by the media. |
| `void` | `https://developer.android.com/reference/androidx/media3/exoplayer/DefaultLivePlaybackSpeedControl#setTargetLiveOffsetOverrideUs(long)(long liveOffsetUs)` Sets the target live offset in microseconds that overrides the live offset `https://developer.android.com/reference/androidx/media3/exoplayer/LivePlaybackSpeedControl#setLiveConfiguration(androidx.media3.common.MediaItem.LiveConfiguration)` by the media. |

## Constants

### DEFAULT_FALLBACK_MAX_PLAYBACK_SPEED

```
public static final float DEFAULT_FALLBACK_MAX_PLAYBACK_SPEED = 1.03f
```

The default maximum factor by which playback can be sped up that should be used if no maximum playback speed is defined by the media.

### DEFAULT_FALLBACK_MIN_PLAYBACK_SPEED

```
public static final float DEFAULT_FALLBACK_MIN_PLAYBACK_SPEED = 0.97f
```

The default minimum factor by which playback can be sped up that should be used if no minimum playback speed is defined by the media.

### DEFAULT_MAX_LIVE_OFFSET_ERROR_MS_FOR_UNIT_SPEED

```
public static final long DEFAULT_MAX_LIVE_OFFSET_ERROR_MS_FOR_UNIT_SPEED = 20
```

The default maximum difference between the current live offset and the target live offset, in milliseconds, for which unit speed (1.0f) is used.

### DEFAULT_MIN_POSSIBLE_LIVE_OFFSET_SMOOTHING_FACTOR

```
public static final float DEFAULT_MIN_POSSIBLE_LIVE_OFFSET_SMOOTHING_FACTOR = 0.999f
```

The default smoothing factor when smoothing the minimum possible live offset that can be achieved during playback.

### DEFAULT_MIN_UPDATE_INTERVAL_MS

```
public static final long DEFAULT_MIN_UPDATE_INTERVAL_MS = 1000
```

The default `https://developer.android.com/reference/androidx/media3/exoplayer/DefaultLivePlaybackSpeedControl.Builder#setMinUpdateIntervalMs(long)` between playback speed changes, in milliseconds.

### DEFAULT_PROPORTIONAL_CONTROL_FACTOR

```
public static final float DEFAULT_PROPORTIONAL_CONTROL_FACTOR = 0.1f
```

The default `https://developer.android.com/reference/androidx/media3/exoplayer/DefaultLivePlaybackSpeedControl.Builder#setProportionalControlFactor(float)` used to adjust the playback speed.

### DEFAULT_TARGET_LIVE_OFFSET_INCREMENT_ON_REBUFFER_MS

```
public static final long DEFAULT_TARGET_LIVE_OFFSET_INCREMENT_ON_REBUFFER_MS = 500
```

The default increment applied to the target live offset each time the player is rebuffering, in milliseconds

## Public methods

### getAdjustedPlaybackSpeed

```
public float getAdjustedPlaybackSpeed(long liveOffsetUs, long bufferedDurationUs)
```

Returns the adjusted playback speed in order get closer towards the `https://developer.android.com/reference/androidx/media3/exoplayer/LivePlaybackSpeedControl#getTargetLiveOffsetUs()`.

| Parameters |
|---|---|
| `long liveOffsetUs` | The current live offset, in microseconds. |
| `long bufferedDurationUs` | The duration of media that's currently buffered, in microseconds. |

| Returns |
|---|---|
| `float` | The adjusted factor by which playback should be sped up. |

### getTargetLiveOffsetUs

```
public long getTargetLiveOffsetUs()
```

Returns the current target live offset, in microseconds, or `https://developer.android.com/reference/androidx/media3/common/C#TIME_UNSET()` if no target live offset is defined for the current media.

### notifyRebuffer

```
public void notifyRebuffer()
```

Notifies the live playback speed control that a rebuffer occurred.

A rebuffer is defined to be caused by buffer depletion rather than a user action. Hence this method is not called during initial buffering or when buffering as a result of a seek operation.

### setLiveConfiguration

```
public void setLiveConfiguration(MediaItem.LiveConfiguration liveConfiguration)
```

Sets the live configuration defined by the media.

| Parameters |
|---|---|
| `https://developer.android.com/reference/androidx/media3/common/MediaItem.LiveConfiguration liveConfiguration` | The `https://developer.android.com/reference/androidx/media3/common/MediaItem.LiveConfiguration` as defined by the media. |

### setTargetLiveOffsetOverrideUs

```
public void setTargetLiveOffsetOverrideUs(long liveOffsetUs)
```

Sets the target live offset in microseconds that overrides the live offset `https://developer.android.com/reference/androidx/media3/exoplayer/LivePlaybackSpeedControl#setLiveConfiguration(androidx.media3.common.MediaItem.LiveConfiguration)` by the media. Passing `C.TIME_UNSET` deletes a previous override.

If no target live offset is configured by `https://developer.android.com/reference/androidx/media3/exoplayer/LivePlaybackSpeedControl#setLiveConfiguration(androidx.media3.common.MediaItem.LiveConfiguration)`, this override has no effect.