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# sourceReadOnlyPixelBuffer(byTrackID:)

Returns the source CVReadOnlyPixelBuffer for the given track ID.
If the track contains tagged buffers, a pixel buffer from one of the tagged buffers will be returned.

```
func sourceReadOnlyPixelBuffer(byTrackID trackID: CMPersistentTrackID) -> CVReadOnlyPixelBuffer?
```

## Parameters

`trackID`

The track ID for the requested source frame.

## Return Value

the source CVReadOnlyPixelBuffer for the given track ID.

---

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