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  "framework" : "CoreMedia",
  "identifier" : "/documentation/CoreMedia/metadata-base-data-types",
  "metadataVersion" : "0.1.0",
  "role" : "collectionGroup",
  "title" : "Metadata Base Data Types"
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# Metadata Base Data Types

Constants that describe metadata base data types.

## Topics

### Constants

[`let kCMMetadataBaseDataType_RawData: CFString`](/documentation/CoreMedia/kCMMetadataBaseDataType_RawData)

A sequence of bytes whose interpretation based upon an agreement between the reader and the writer.

[`let kCMMetadataBaseDataType_UTF8: CFString`](/documentation/CoreMedia/kCMMetadataBaseDataType_UTF8)

UTF-8 string.

[`let kCMMetadataBaseDataType_UTF16: CFString`](/documentation/CoreMedia/kCMMetadataBaseDataType_UTF16)

UTF-16 string.

[`let kCMMetadataBaseDataType_GIF: CFString`](/documentation/CoreMedia/kCMMetadataBaseDataType_GIF)

GIF image.

[`let kCMMetadataBaseDataType_JPEG: CFString`](/documentation/CoreMedia/kCMMetadataBaseDataType_JPEG)

JPEG image.

[`let kCMMetadataBaseDataType_PNG: CFString`](/documentation/CoreMedia/kCMMetadataBaseDataType_PNG)

PNG image.

[`let kCMMetadataBaseDataType_BMP: CFString`](/documentation/CoreMedia/kCMMetadataBaseDataType_BMP)

BMP image.

[`let kCMMetadataBaseDataType_Float32: CFString`](/documentation/CoreMedia/kCMMetadataBaseDataType_Float32)

32-bit big endian floating point number.

[`let kCMMetadataBaseDataType_Float64: CFString`](/documentation/CoreMedia/kCMMetadataBaseDataType_Float64)

64-bit big endian floating point number.

[`let kCMMetadataBaseDataType_SInt8: CFString`](/documentation/CoreMedia/kCMMetadataBaseDataType_SInt8)

8-bit signed integer.

[`let kCMMetadataBaseDataType_SInt16: CFString`](/documentation/CoreMedia/kCMMetadataBaseDataType_SInt16)

16-bit big endian signed integer.

[`let kCMMetadataBaseDataType_SInt32: CFString`](/documentation/CoreMedia/kCMMetadataBaseDataType_SInt32)

32-bit big endian signed integer.

[`let kCMMetadataBaseDataType_SInt64: CFString`](/documentation/CoreMedia/kCMMetadataBaseDataType_SInt64)

64-bit big endian signed integer.

[`let kCMMetadataBaseDataType_UInt8: CFString`](/documentation/CoreMedia/kCMMetadataBaseDataType_UInt8)

8-bit unsigned integer.

[`let kCMMetadataBaseDataType_UInt16: CFString`](/documentation/CoreMedia/kCMMetadataBaseDataType_UInt16)

16-bit big endian unsigned integer.

[`let kCMMetadataBaseDataType_UInt32: CFString`](/documentation/CoreMedia/kCMMetadataBaseDataType_UInt32)

32-bit big endian unsigned integer.

[`let kCMMetadataBaseDataType_UInt64: CFString`](/documentation/CoreMedia/kCMMetadataBaseDataType_UInt64)

64-bit big endian unsigned integer.

[`let kCMMetadataBaseDataType_PointF32: CFString`](/documentation/CoreMedia/kCMMetadataBaseDataType_PointF32)

Consists of two 32-bit big endian floating point values, the x and y values, respectively.

[`let kCMMetadataBaseDataType_DimensionsF32: CFString`](/documentation/CoreMedia/kCMMetadataBaseDataType_DimensionsF32)

Consists of a 32-bit big endian floating point x value followed by a 32-bit floating point y value.

[`let kCMMetadataBaseDataType_RectF32: CFString`](/documentation/CoreMedia/kCMMetadataBaseDataType_RectF32)

Consists of four 32-bit big endian floating point values, the origin’s x, origin’s y, width and height values, respectively. May also be interpreted as a 32-bit floating point origin followed by a 32-bit floating point dimension.

[`let kCMMetadataBaseDataType_AffineTransformF64: CFString`](/documentation/CoreMedia/kCMMetadataBaseDataType_AffineTransformF64)

A type that identifies a 3x3 matrix of 64-bit big endian floating point numbers in a row-major order that specify an affine transform.

[`let kCMMetadataBaseDataType_PerspectiveTransformF64: CFString`](/documentation/CoreMedia/kCMMetadataBaseDataType_PerspectiveTransformF64)

A 3x3 matrix of 64-bit big endian floating point numbers the system stores in row-major order that specify a perspective transform.

[`let kCMMetadataBaseDataType_PolygonF32: CFString`](/documentation/CoreMedia/kCMMetadataBaseDataType_PolygonF32)

Three or more pairs of 32-bit floating point numbers (x and y values) that define the vertices of a polygon.

[`let kCMMetadataBaseDataType_PolylineF32: CFString`](/documentation/CoreMedia/kCMMetadataBaseDataType_PolylineF32)

Two or more pairs of 32-bit floating point numbers (x and y values) that define a multi-segmented line.

[`let kCMMetadataBaseDataType_JSON: CFString`](/documentation/CoreMedia/kCMMetadataBaseDataType_JSON)

UTF-8 encoded JSON data.


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