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# VTHDRPerFrameMetadataGenerationSessionAttachMetadata

Attaches per-frame metadata to the pixel buffer and the backing IOSurface.

```
extern OSStatus VTHDRPerFrameMetadataGenerationSessionAttachMetadata(VTHDRPerFrameMetadataGenerationSessionRef hdrPerFrameMetadataGenerationSession, CVPixelBufferRef pixelBuffer, Boolean sceneChange);
```

## Discussion

Call this to analyze and attach HDR Metadata. This call will change CVPixelBuffer attachments and backing IOSurface attachments.

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