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# VTHDRPerFrameMetadataGenerationSessionRef

A mechanism for generating HDR Per Frame Metadata and attaching that metadata to a pixel buffer and the backing IOSurface.

```
typedef struct OpaqueVTHDRPerFrameMetadataGenerationSession * VTHDRPerFrameMetadataGenerationSessionRef;
```

## Discussion

This object is a CF type, so call `CFRelease` to release your object reference.

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