---
title: CMMetadataDataTypeRegistryGetBaseDataTypes()
framework: coremedia
role: symbol
role_heading: Function
path: coremedia/cmmetadatadatatyperegistrygetbasedatatypes()
---

# CMMetadataDataTypeRegistryGetBaseDataTypes()

Returns an array of base data type identifiers.

## Declaration

```swift
func CMMetadataDataTypeRegistryGetBaseDataTypes() -> CFArray?
```

## Return Value

Return Value An array of the base data types to which all others must conform.

## Discussion

Discussion There are a set of base data types that seed the data type registry. All valid data types will have their conformance search end with a base data type.

## See Also

### Inspecting Metadata

- [CMMetadataDataTypeRegistryDataTypeIsRegistered(_:)](coremedia/cmmetadatadatatyperegistrydatatypeisregistered(_:).md)
- [CMMetadataDataTypeRegistryGetDataTypeDescription(_:)](coremedia/cmmetadatadatatyperegistrygetdatatypedescription(_:).md)
- [CMMetadataDataTypeRegistryGetConformingDataTypes(_:)](coremedia/cmmetadatadatatyperegistrygetconformingdatatypes(_:).md)
- [CMMetadataDataTypeRegistryDataTypeConformsToDataType(_:conformsTo:)](coremedia/cmmetadatadatatyperegistrydatatypeconformstodatatype(_:conformsto:).md)
- [CMMetadataDataTypeRegistryDataTypeIsBaseDataType(_:)](coremedia/cmmetadatadatatyperegistrydatatypeisbasedatatype(_:).md)
- [CMMetadataDataTypeRegistryGetBaseDataTypeForConformingDataType(_:)](coremedia/cmmetadatadatatyperegistrygetbasedatatypeforconformingdatatype(_:).md)