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# sourceTaggedDynamicBuffers(byTrackID:)

Returns the source tagged dynamic buffers for the given track ID.
Returns nil if the video track does not contain tagged buffers, or if the track does not contain video. This function should only be called when supportsSourceTaggedBuffers is YES.

```
func sourceTaggedDynamicBuffers(byTrackID trackID: CMPersistentTrackID) -> [CMTaggedDynamicBuffer]?
```

## Return Value

the source CMTaggedBuffer array for the given track ID.

---

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