# DashWrappingSegmentIndex

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

*** ** * ** ***


```
@UnstableApi
public final class DashWrappingSegmentIndex implements DashSegmentIndex
```

<br />

*** ** * ** ***

An implementation of `https://developer.android.com/reference/androidx/media3/exoplayer/dash/DashSegmentIndex` that wraps a `https://developer.android.com/reference/androidx/media3/extractor/ChunkIndex` parsed from a media stream.

## Summary

| ### Public constructors |
|---|
| `https://developer.android.com/reference/androidx/media3/exoplayer/dash/DashWrappingSegmentIndex#DashWrappingSegmentIndex(androidx.media3.extractor.ChunkIndex,long)(https://developer.android.com/reference/androidx/media3/extractor/ChunkIndex chunkIndex, long timeOffsetUs)` |

| ### Public methods |
|---|---|
| `long` | `https://developer.android.com/reference/androidx/media3/exoplayer/dash/DashWrappingSegmentIndex#getAvailableSegmentCount(long,long)(long periodDurationUs, long nowUnixTimeUs)` Returns the number of available segments in the index. |
| `long` | `https://developer.android.com/reference/androidx/media3/exoplayer/dash/DashWrappingSegmentIndex#getDurationUs(long,long)(long segmentNum, long periodDurationUs)` Returns the duration of a segment. |
| `long` | `https://developer.android.com/reference/androidx/media3/exoplayer/dash/DashWrappingSegmentIndex#getFirstAvailableSegmentNum(long,long)(long periodDurationUs, long nowUnixTimeUs)` Returns the segment number of the first available segment in the index. |
| `long` | `https://developer.android.com/reference/androidx/media3/exoplayer/dash/DashWrappingSegmentIndex#getFirstSegmentNum()()` Returns the segment number of the first defined segment in the index. |
| `long` | `https://developer.android.com/reference/androidx/media3/exoplayer/dash/DashWrappingSegmentIndex#getNextSegmentAvailableTimeUs(long,long)( long periodDurationUs, long nowUnixTimeUs )` Returns the time, in microseconds, at which a new segment becomes available, or `https://developer.android.com/reference/androidx/media3/common/C#TIME_UNSET()` if not applicable. |
| `long` | `https://developer.android.com/reference/androidx/media3/exoplayer/dash/DashWrappingSegmentIndex#getSegmentCount(long)(long periodDurationUs)` Returns the number of segments defined in the index, or `https://developer.android.com/reference/androidx/media3/exoplayer/dash/DashSegmentIndex#INDEX_UNBOUNDED()`. |
| `long` | `https://developer.android.com/reference/androidx/media3/exoplayer/dash/DashWrappingSegmentIndex#getSegmentNum(long,long)(long timeUs, long periodDurationUs)` Returns `getFirstSegmentNum()` if the index has no segments or if the given media time is earlier than the start of the first segment. |
| `https://developer.android.com/reference/androidx/media3/exoplayer/dash/manifest/RangedUri` | `https://developer.android.com/reference/androidx/media3/exoplayer/dash/DashWrappingSegmentIndex#getSegmentUrl(long)(long segmentNum)` Returns a `https://developer.android.com/reference/androidx/media3/exoplayer/dash/manifest/RangedUri` defining the location of a segment. |
| `long` | `https://developer.android.com/reference/androidx/media3/exoplayer/dash/DashWrappingSegmentIndex#getTimeUs(long)(long segmentNum)` Returns the start time of a segment. |
| `boolean` | `https://developer.android.com/reference/androidx/media3/exoplayer/dash/DashWrappingSegmentIndex#isExplicit()()` Returns true if segments are defined explicitly by the index. |

| ### Inherited Constants |
|---|
| From [androidx.media3.exoplayer.dash.DashSegmentIndex](https://developer.android.com/reference/androidx/media3/exoplayer/dash/DashSegmentIndex) |---|---| | `static final int` | `https://developer.android.com/reference/androidx/media3/exoplayer/dash/DashSegmentIndex#INDEX_UNBOUNDED() = -1` | |

## Public constructors

### DashWrappingSegmentIndex

```
public DashWrappingSegmentIndex(ChunkIndex chunkIndex, long timeOffsetUs)
```

| Parameters |
|---|---|
| `https://developer.android.com/reference/androidx/media3/extractor/ChunkIndex chunkIndex` | The `https://developer.android.com/reference/androidx/media3/extractor/ChunkIndex` to wrap. |
| `long timeOffsetUs` | An offset to subtract from the times in the wrapped index, in microseconds. |

## Public methods

### getAvailableSegmentCount

```
public long getAvailableSegmentCount(long periodDurationUs, long nowUnixTimeUs)
```

Returns the number of available segments in the index.

| Parameters |
|---|---|
| `long periodDurationUs` | The duration of the enclosing period in microseconds, or `https://developer.android.com/reference/androidx/media3/common/C#TIME_UNSET()` if the period's duration is not yet known. |
| `long nowUnixTimeUs` | The current time in milliseconds since the Unix epoch. |

| Returns |
|---|---|
| `long` | The number of available segments in the index. |

### getDurationUs

```
public long getDurationUs(long segmentNum, long periodDurationUs)
```

Returns the duration of a segment.

| Parameters |
|---|---|
| `long segmentNum` | The segment number. |
| `long periodDurationUs` | The duration of the enclosing period in microseconds, or `https://developer.android.com/reference/androidx/media3/common/C#TIME_UNSET()` if the period's duration is not yet known. |

| Returns |
|---|---|
| `long` | The duration of the segment, in microseconds. |

### getFirstAvailableSegmentNum

```
public long getFirstAvailableSegmentNum(long periodDurationUs, long nowUnixTimeUs)
```

Returns the segment number of the first available segment in the index.

| Parameters |
|---|---|
| `long periodDurationUs` | The duration of the enclosing period in microseconds, or `https://developer.android.com/reference/androidx/media3/common/C#TIME_UNSET()` if the period's duration is not yet known. |
| `long nowUnixTimeUs` | The current time in milliseconds since the Unix epoch. |

| Returns |
|---|---|
| `long` | The number of the first available segment. |

### getFirstSegmentNum

```
public long getFirstSegmentNum()
```

Returns the segment number of the first defined segment in the index.

### getNextSegmentAvailableTimeUs

```
public long getNextSegmentAvailableTimeUs(
    long periodDurationUs,
    long nowUnixTimeUs
)
```

Returns the time, in microseconds, at which a new segment becomes available, or `https://developer.android.com/reference/androidx/media3/common/C#TIME_UNSET()` if not applicable.

| Parameters |
|---|---|
| `long periodDurationUs` | The duration of the enclosing period in microseconds, or `https://developer.android.com/reference/androidx/media3/common/C#TIME_UNSET()` if the period's duration is not yet known. |
| `long nowUnixTimeUs` | The current time in milliseconds since the Unix epoch. |

| Returns |
|---|---|
| `long` | The time, in microseconds, at which a new segment becomes available, or `https://developer.android.com/reference/androidx/media3/common/C#TIME_UNSET()` if not applicable. |

### getSegmentCount

```
public long getSegmentCount(long periodDurationUs)
```

Returns the number of segments defined in the index, or `https://developer.android.com/reference/androidx/media3/exoplayer/dash/DashSegmentIndex#INDEX_UNBOUNDED()`.

An unbounded index occurs if a dynamic manifest uses SegmentTemplate elements without a SegmentTimeline element, and if the period duration is not yet known. In this case the caller can query the available segment using `https://developer.android.com/reference/androidx/media3/exoplayer/dash/DashSegmentIndex#getFirstAvailableSegmentNum(long,long)` and `https://developer.android.com/reference/androidx/media3/exoplayer/dash/DashSegmentIndex#getAvailableSegmentCount(long,long)`.

| Parameters |
|---|---|
| `long periodDurationUs` | The duration of the enclosing period in microseconds, or `https://developer.android.com/reference/androidx/media3/common/C#TIME_UNSET()` if the period's duration is not yet known. |

| Returns |
|---|---|
| `long` | The number of segments in the index, or `https://developer.android.com/reference/androidx/media3/exoplayer/dash/DashSegmentIndex#INDEX_UNBOUNDED()`. |

### getSegmentNum

```
public long getSegmentNum(long timeUs, long periodDurationUs)
```

Returns `getFirstSegmentNum()` if the index has no segments or if the given media time is earlier than the start of the first segment. Returns `getFirstSegmentNum() +
getSegmentCount() - 1` if the given media time is later than the end of the last segment. Otherwise, returns the segment number of the segment containing the given media time.

| Parameters |
|---|---|
| `long timeUs` | The time in microseconds. |
| `long periodDurationUs` | The duration of the enclosing period in microseconds, or `https://developer.android.com/reference/androidx/media3/common/C#TIME_UNSET()` if the period's duration is not yet known. |

| Returns |
|---|---|
| `long` | The segment number of the corresponding segment. |

### getSegmentUrl

```
public RangedUri getSegmentUrl(long segmentNum)
```

Returns a `https://developer.android.com/reference/androidx/media3/exoplayer/dash/manifest/RangedUri` defining the location of a segment.

| Parameters |
|---|---|
| `long segmentNum` | The segment number. |

| Returns |
|---|---|
| `https://developer.android.com/reference/androidx/media3/exoplayer/dash/manifest/RangedUri` | The `https://developer.android.com/reference/androidx/media3/exoplayer/dash/manifest/RangedUri` defining the location of the data. |

### getTimeUs

```
public long getTimeUs(long segmentNum)
```

Returns the start time of a segment.

| Parameters |
|---|---|
| `long segmentNum` | The segment number. |

| Returns |
|---|---|
| `long` | The corresponding start time in microseconds. |

### isExplicit

```
public boolean isExplicit()
```

Returns true if segments are defined explicitly by the index.

If true is returned, each segment is defined explicitly by the index data, and all of the listed segments are guaranteed to be available at the time when the index was obtained.

If false is returned then segment information was derived from properties such as a fixed segment duration. If the presentation is dynamic, it's possible that only a subset of the segments are available.

| Returns |
|---|---|
| `boolean` | Whether segments are defined explicitly by the index. |