---
title: Core Media Constants
framework: Core Media
role: collectionGroup
role_heading: API Collection
path: coremedia/core-media-constants
---

# Core Media Constants

## Overview

Overview This document describes constants defined in the Core Media framework not defined elsewhere in this reference.

## Topics

### Constants

- [COREMEDIA_DECLARE_BRIDGED_TYPES](coremedia/coremedia_declare_bridged_types.md)
- [COREMEDIA_DECLARE_NULLABILITY](coremedia/coremedia_declare_nullability.md)
- [COREMEDIA_DECLARE_NULLABILITY_BEGIN_END](coremedia/coremedia_declare_nullability_begin_end.md)
- [COREMEDIA_DECLARE_RETURNS_NOT_RETAINED_ON_PARAMETERS](coremedia/coremedia_declare_returns_not_retained_on_parameters.md)
- [COREMEDIA_DECLARE_RETURNS_RETAINED](coremedia/coremedia_declare_returns_retained.md)
- [COREMEDIA_DECLARE_RETURNS_RETAINED_ON_PARAMETERS](coremedia/coremedia_declare_returns_retained_on_parameters.md)
- [COREMEDIA_USE_DERIVED_ENUMS_FOR_CONSTANTS](coremedia/coremedia_use_derived_enums_for_constants.md)
- [CMITEMCOUNT_MAX](coremedia/cmitemcount_max.md)
- [COREMEDIA_CMBASECLASS_VERSION_IS_POINTER_ALIGNED](coremedia/coremedia_cmbaseclass_version_is_pointer_aligned.md)
- [COREMEDIA_DECLARE_RELEASES_ARGUMENT](coremedia/coremedia_declare_releases_argument.md)
- [COREMEDIA_FALSE](coremedia/coremedia_false.md)
- [COREMEDIA_TRUE](coremedia/coremedia_true.md)
- [COREMEDIA_USE_ALIGNED_CMBASECLASS_VERSION](coremedia/coremedia_use_aligned_cmbaseclass_version.md)
- [CMTIMEBASE_USE_SOURCE_TERMINOLOGY](coremedia/cmtimebase_use_source_terminology.md)
- [COREMEDIA_DECLARE_RETURNS_RETAINED_BLOCK](coremedia/coremedia_declare_returns_retained_block.md)
- [kCMFormatDescriptionExtension_ProjectionKind](coremedia/kcmformatdescriptionextension_projectionkind.md)
- [kCMFormatDescriptionExtension_ViewPackingKind](coremedia/kcmformatdescriptionextension_viewpackingkind.md)
- [kCMFormatDescriptionLogTransferFunction_AppleLog](coremedia/kcmformatdescriptionlogtransferfunction_applelog.md)
- [kCMFormatDescriptionProjectionKind_Rectilinear](coremedia/kcmformatdescriptionprojectionkind_rectilinear.md)
- [kCMFormatDescriptionViewPackingKind_OverUnder](coremedia/kcmformatdescriptionviewpackingkind_overunder.md)
- [kCMFormatDescriptionViewPackingKind_SideBySide](coremedia/kcmformatdescriptionviewpackingkind_sidebyside.md)
- [kCMMetadataDataType_QuickTimeMetadataMilliLux](coremedia/kcmmetadatadatatype_quicktimemetadatamillilux.md)
- [kCMMetadataDataType_QuickTimeMetadataUUID](coremedia/kcmmetadatadatatype_quicktimemetadatauuid.md)
- [kCMMetadataIdentifier_QuickTimeMetadataSceneIlluminance](coremedia/kcmmetadataidentifier_quicktimemetadatasceneilluminance.md)
- [kCMMetadataIdentifier_QuickTimeMetadataSegmentIdentifier](coremedia/kcmmetadataidentifier_quicktimemetadatasegmentidentifier.md)
- [kCMSampleAttachmentKey_HDR10PlusPerFrameData](coremedia/kcmsampleattachmentkey_hdr10plusperframedata.md)
- [kCMTagProjectionTypeHalfEquirectangular](coremedia/kcmtagprojectiontypehalfequirectangular.md)
- [kCMTextMarkupAttribute_FontFamilyNameList](coremedia/kcmtextmarkupattribute_fontfamilynamelist.md)
- [kCMFormatDescriptionExtension_ConvertedFromExternalSphericalTags](coremedia/kcmformatdescriptionextension_convertedfromexternalsphericaltags.md)
- [kCMFormatDescriptionProjectionKind_AppleImmersiveVideo](coremedia/kcmformatdescriptionprojectionkind_appleimmersivevideo.md)
- [kCMFormatDescriptionProjectionKind_Equirectangular](coremedia/kcmformatdescriptionprojectionkind_equirectangular.md)
- [kCMFormatDescriptionProjectionKind_HalfEquirectangular](coremedia/kcmformatdescriptionprojectionkind_halfequirectangular.md)
- [kCMFormatDescriptionProjectionKind_ParametricImmersive](coremedia/kcmformatdescriptionprojectionkind_parametricimmersive.md)
- [kCMMetadataBaseDataType_ExtendedRasterRectangleValue](coremedia/kcmmetadatabasedatatype_extendedrasterrectanglevalue.md)
- [kCMMetadataBaseDataType_RasterRectangleValue](coremedia/kcmmetadatabasedatatype_rasterrectanglevalue.md)
- [kCMMetadataIdentifier_QuickTimeMetadataDisplayMaskRectangleMono](coremedia/kcmmetadataidentifier_quicktimemetadatadisplaymaskrectanglemono.md)
- [kCMMetadataIdentifier_QuickTimeMetadataDisplayMaskRectangleStereoLeft](coremedia/kcmmetadataidentifier_quicktimemetadatadisplaymaskrectanglestereoleft.md)
- [kCMMetadataIdentifier_QuickTimeMetadataDisplayMaskRectangleStereoRight](coremedia/kcmmetadataidentifier_quicktimemetadatadisplaymaskrectanglestereoright.md)
- [kCMMetadataIdentifier_QuickTimeMetadataPresentationImmersiveMedia](coremedia/kcmmetadataidentifier_quicktimemetadatapresentationimmersivemedia.md)
- [kCMMetadataIdentifier_QuickTimeMetadataSpatialAudioMix](coremedia/kcmmetadataidentifier_quicktimemetadataspatialaudiomix.md)
- [Camera calibration](coremedia/camera-calibration-constants.md)

### Type Aliases

- [CMBaseClassVersion](coremedia/cmbaseclassversion.md)
- [CMStructVersion](coremedia/cmstructversion.md)

## See Also

### Reference

- [Core Media Functions](coremedia/core-media-functions.md)
- [Core Media Type Aliases](coremedia/core-media-type-aliases.md)