---
title: kVTSampleAttachmentQualityMetricsKey_ChromaBlueMeanSquaredError
framework: videotoolbox
role: symbol
role_heading: Global Variable
path: videotoolbox/kvtsampleattachmentqualitymetricskey_chromabluemeansquarederror
---

# kVTSampleAttachmentQualityMetricsKey_ChromaBlueMeanSquaredError

## Declaration

```swift
let kVTSampleAttachmentQualityMetricsKey_ChromaBlueMeanSquaredError: CFString
```

## See Also

### Quality Metrics

- [kVTCompressionPropertyKey_CalculateMeanSquaredError](videotoolbox/kvtcompressionpropertykey_calculatemeansquarederror.md)
- [kVTSampleAttachmentKey_QualityMetrics](videotoolbox/kvtsampleattachmentkey_qualitymetrics.md)
- [kVTSampleAttachmentQualityMetricsKey_ChromaRedMeanSquaredError](videotoolbox/kvtsampleattachmentqualitymetricskey_chromaredmeansquarederror.md)
- [kVTSampleAttachmentQualityMetricsKey_LumaMeanSquaredError](videotoolbox/kvtsampleattachmentqualitymetricskey_lumameansquarederror.md)