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Enumeration registry

registry

The listings on this page are generated by scripts/gen-omid-spec.mjs from official IAB Tech Lab sources, with descriptions in the original English; see the page footer for the collection baseline.

On this page

Role & scope
Event & error types
Session, ownership & access mode
Creative, impression criteria & playback state
Geometry, obstructions & view markup
App & device state
Deprecated and superseded values
Related chapters

Role & scope

A machine-readable registry of every Open Measurement Interface Definition (OMID) enumeration constant: event types, impression criteria, creative types, access modes, player states, obstruction reasons and more, with verbatim official descriptions and deprecation flags (e.g. AccessMode.DOMAIN removed in 1.5.4, AdEventType.VIDEO superseded by MEDIA).

Enums: 26
Values: 129
Spec version: OMID 1.6
Current baseline: 2026-09-22

Event & error types

AdEventTypejs · 22

List of all OMID ad event types.

Constant	Literal value	Official description
IMPRESSION	impression	The OMID provider has recorded an impression for this ad. For video ads, this corresponds to the VAST <Impression> and should be fired simultaneously with that event. Constant has value 'impression'.
LOADED	loaded	The OM integration has loaded the display, video, or audio ad creative's assets. For video and audio ads, it has buffered the creative’s media to the extent that it is ready to play the media. Corresponds to the VAST 'loaded' event. Constant has value 'loaded'.
GEOMETRY_CHANGE	geometryChange	The geometry state has changed. Specifically, this event is fired every time the ad container state changes such that any field of the viewport or ad view would change value from the previous report. Provides full geometry data of the registered ad view including obstructions along with any detected reason codes. All size and location units reported in the event data are in independent pixels, and all coordinates are relative to the screen coordinates. Constant has value 'geometryChange'.
SESSION_START	sessionStart	This event fires as soon as the OMID provider has initialized and has the necessary data to fill in the 'context' and 'verificationParameters' of the event data. It does not imply that the ad has rendered or the video has started playing; it only marks the initialization of the of the ad session. This is always the first event fired for a session. Constant has value 'sessionStart'.
SESSION_ERROR	sessionError	This event is fired following a playback, rendering, or other ad-related error, which may be session terminal or recoverable. In the case of non-recoverable errors, this event does not replace 'sessionFinish', which still must be fired following the 'sessionError' event. Constant has value 'sessionError'.
SESSION_FINISH	sessionFinish	This event is fired when the ad session has terminated and indicates that verification resources should start clean up and handle end-of-session reporting. This is the always the last event sent for a session. Constant has value 'sessionFinish'.
MEDIA	media	Convenient shorthand that registers for all media events: 'loaded', 'start', 'firstQuartile', 'midpoint', 'thirdQuartile', 'complete', 'pause', 'resume', 'bufferStart', 'bufferFinish', 'skipped', 'volumeChange', 'playerStateChange', and 'adUserInteraction'. OM SDK never sends events with this type. Constant has value 'media'.
VIDEOdeprecated	video	Registers for the same events as 'media'. Superseded by value 'media'; OM SDK continues to support this value for backwards compatibility. OM SDK never sends events with this type. Constant has value 'video'.
START	start	Media-only event. The player began playback of the video ad creative. Corresponds to the VAST 'start' event. Constant has value 'start'.
FIRST_QUARTILE	firstQuartile	Media-only event. The creative played continuously for at least 25% of the total duration. Corresponds to the VAST 'firstQuartile' event. Constant has value 'firstQuartile'.
MIDPOINT	midpoint	Media-only event. The creative played continuously for at least 50% of the total duration. Corresponds to the VAST midpoint event. Constant has value 'midpoint'.
THIRD_QUARTILE	thirdQuartile	Media-only event. The creative played continuously for at least 75% of the total duration. Corresponds to the VAST 'thirdQuartile' event. Constant has value 'thirdQuartile'.
COMPLETE	complete	Media-only event. The creative played to the end for 100% of the total duration. Corresponds to the VAST 'complete' event. Constant has value 'complete'.
PAUSE	pause	Media-only event. Playback was stopped in a way from which it may later be resumed, due to user interaction. Corresponds to the VAST 'pause' event. Constant has value 'pause'.
RESUME	resume	Media-only event. Playback resumed following a user-originated pause. Corresponds to the VAST 'resume' event. Constant has value 'resume'.
BUFFER_START	bufferStart	Media-only event. Playback was stopped in a way from which it may later be resumed, due to a cause other than user interaction (generally buffering from insufficient available video data). Constant has value 'bufferStart'.
BUFFER_FINISH	bufferFinish	Media-only event. Playback has resumed following a non-user-originated pause. Constant has value 'bufferFinish'.
SKIPPED	skipped	Media-only event. The user activated a control which caused ad playback to terminate. Corresponds to the VAST 'skip' event. Constant has value 'skipped'.
VOLUME_CHANGE	volumeChange	Media-only event. The player and/or device volume has changed. Constant has value 'volumeChange'.
PLAYER_STATE_CHANGE	playerStateChange	Media-only event. The player has changed playback states, generally to resize. This includes moving from non-fullscreen to fullscreen state. The assumption is that at start time the video is in the normal state. If playback begins when the player is in a minimized or fullscreen state, then this event is fired immediately following start in order to reflect the current state. Constant has value 'playerStateChange'.
AD_USER_INTERACTION	adUserInteraction	The user has interacted with the ad outside of any standard playback controls (e.g. clicked the ad to load an ad landing page). NOTE: If this interaction causes playback to pause, then this event should be followed by a separate 'pause' event. Constant has value 'adUserInteraction'.
STATE_CHANGEdeprecated	stateChange	Not part of OMID API, and OM SDK never sends events with this type. This constant will be removed in a future release of OM SDK.

MediaEventTypejs · 14

Enum for ad events type representing media events.

Constant	Literal value	Official description
LOADED	loaded	—
START	start	—
FIRST_QUARTILE	firstQuartile	—
MIDPOINT	midpoint	—
THIRD_QUARTILE	thirdQuartile	—
COMPLETE	complete	—
PAUSE	pause	—
RESUME	resume	—
BUFFER_START	bufferStart	—
BUFFER_FINISH	bufferFinish	—
SKIPPED	skipped	—
VOLUME_CHANGE	volumeChange	—
PLAYER_STATE_CHANGE	playerStateChange	—
AD_USER_INTERACTION	adUserInteraction	—

ErrorTypejs · ios · iOS OMIDErrorType · 3

The types of error notifications in 'sessionError' events.

Constant	Literal value	Official description
GENERIC	generic	The integration is publishing a generic error to verification scripts. Used as a catch-all for non-media issues. Constant has value 'generic'.
VIDEOdeprecated	video	The integration is publishing a video error to verification scripts. Used for video-related rendering or loading errors. This type of error has been superseded by 'media'. Constant has value 'video'.
MEDIA	media	The integration is publishing a media error to verification scripts. Used for media-related rendering or loading errors. Constant has value 'media'.

InteractionTypejs · ios · iOS OMIDInteractionType · 2

The types of user interactions with ads in a media player.

Constant	Literal value	Official description
CLICK	click	The user clicked to load the ad's landing page. Constant has value 'click'.
INVITATION_ACCEPT	invitationAccept	The user engaged with ad content to load a separate experience. Constant has value 'invitationAccept'.

Session, ownership & access mode

AdSessionTypejs · 3

Enum for Ad Session Type. Possible values include; "native" or "html" or "javascript".

Constant	Literal value	Official description
NATIVE	native	—
HTML	html	—
JAVASCRIPT	javascript	—

SessionOwnerjs · ios · iOS OMIDOwner · 2

Enum describing who owns a session (starts and finishes it).

Constant	Literal value	Official description
JAVASCRIPT	javascript	—
NATIVE	native	—

EventOwnerjs · ios · iOS OMIDOwner · 3

Enum describing who owns an event type.

Constant	Literal value	Official description
NATIVE	native	—
JAVASCRIPT	javascript	—
NONE	none	—

AccessModejs · 3

Enum for sandboxing mode. FULL implies both that verification code has access to the creative element and that OMSDK will provide a reference to that creative element via video/slotElement in the context.

Constant	Literal value	Official description
FULL	full	—
DOMAINdeprecated	domain	—
LIMITED	limited	—

Environmentjs · 2

Enum for Environment OM SDK JS is running in.

Constant	Literal value	Official description
APP	app	—
WEB	web	—

CommunicationTypejs · 3

Constant	Literal value	Official description
NONE	NONE	—
DIRECT	DIRECT	—
POST_MESSAGE	POST_MESSAGE	—

MessageMethodjs · 1

Values for the `method` of a particular message sent to or from the OM SDK service. The "method" identifies the purpose of the message and determines how its arguments will be interpreted. TODO(OMSDK-930): Include all methods used for client-service communication.

Constant	Literal value	Official description
IDENTIFY_SERVICE_WINDOW	identifyServiceWindow	—

OmidImplementerjs · 1

Identifier of party providing OMID.

Constant	Literal value	Official description
OMSDK	omsdk	—

Creative, impression criteria & playback state

CreativeTypejs · ios · iOS OMIDCreativeType · 5

The type of ad creative being measured in the ad session.

Constant	Literal value	Official description
DEFINED_BY_JAVASCRIPT	definedByJavaScript	Creative type needs to be set by JavaScript session script. Constant has value 'definedByJavaScript'.
HTML_DISPLAY	htmlDisplay	Creatives measured using display methodology that are trafficked as HTML. Rendered in webview. Verification scripts can wrap creative or be in resources. Constant has value 'htmlDisplay'.
NATIVE_DISPLAY	nativeDisplay	Creatives measured using display methodology that are trafficked as JSON or other format for structured data. Rendered by native code. Verification scripts can be in resources only. Constant has value 'nativeDisplay'.
VIDEO	video	Creatives measured using video methodology. Rendered in many kinds of placements (such as instream, outstream, banner, in-feed, etc.). Verification scripts can be in resources only. Constant has value 'video'.
AUDIO	audio	Creatives measured using audio methodology. OMID does not provide any visibility data. Verification scripts can be in resources only. Constant has value 'audio'.

ImpressionTypejs · ios · iOS OMIDImpressionType · 8

The criterion for an ad session’s OMID impression event. Declaring an impression type makes it easier to understand discrepancies between measurers of the ad session, since many metrics depend on impressions.

Constant	Literal value	Official description
DEFINED_BY_JAVASCRIPT	definedByJavaScript	Impression type needs to be set by JavaScript session script. Constant has value 'definedByJavaScript'.
UNSPECIFIED	unspecified	The integration is not declaring the criteria for the OMID impression. This is the default impression type for OMID 1.2 and for integrations that don't set an impression type in an ad session. Constant has value 'unspecified'.
LOADED	loaded	The integration is using count-on-download criteria for the OMID impression. Constant has value 'loaded'.
BEGIN_TO_RENDER	beginToRender	The integration is uing begin-to-render criteria for the OMID impression. Constant has value 'beginToRender'.
ONE_PIXEL	onePixel	The integration is using one-pixel criteria for the OMID impression. Constant has value 'onePixel'.
VIEWABLE	viewable	The integration is using viewable criteria (1 second for display, 2 seconds for video) for the OMID impression. Constant has value 'viewable'.
AUDIBLE	audible	The integration is using audible criteria (2 seconds of playback with non-zero volume) for the OMID impression. Constant has value 'audible'.
OTHER	other	The integration's criteria uses none the above for the OMID impression. Constant has value 'other'.

MediaTypejs · 2

Type of ad media.

Constant	Literal value	Official description
DISPLAY	display	—
VIDEO	video	—

VideoPositionjs · ios · android · iOS OMIDPosition · Android Position · 4

The positions of ads relative to media content.

Constant	Literal value	Official description
PREROLL	preroll	The ad plays preceding media content. Constant has value 'preroll'.
MIDROLL	midroll	The ad plays in the middle of media content, or between two separate content media. Constant has value 'midroll'.
POSTROLL	postroll	The ad plays following media content. Constant has value 'postroll'.
STANDALONE	standalone	The ad plays independently of any media content. Constant has value 'standalone'.

VideoPlayerStatejs · ios · android · iOS OMIDPlayerState · Android PlayerState · 5

The playback states of the ad media player.

Constant	Literal value	Official description
MINIMIZED	minimized	The player is collapsed in such a way that the video is hidden. The video may or may not still be progressing in this state, and sound may be audible. This refers specifically to the video player state on the page, and not the state of the browser window. Constant has value 'minimized'.
COLLAPSED	collapsed	The player has been reduced from its original size. The video is still potentially visible. Constant has value 'collapsed'.
NORMAL	normal	The player's default playback size. Constant has value 'normal'.
EXPANDED	expanded	The player has expanded from its original size. Constant has value 'expanded'.
FULLSCREEN	fullscreen	The player has entered fullscreen mode. Constant has value 'fullscreen'.

SupportedFeaturesjs · 2

Enum for features supported by OM SDK JS.

Constant	Literal value	Official description
CONTAINER	clid	—
VIDEO	vlid	—

Geometry, obstructions & view markup

Reasonjs · 11

Enum for reasons for viewability calculation results.

Constant	Literal value	Official description
NOT_FOUND	notFound	—
HIDDEN	hidden	—
BACKGROUNDED	backgrounded	—
PICTURE_IN_PICTURE	pictureInPicture	—
DEVICE_LOCKED	deviceLocked	—
VIEWPORT	viewport	—
OBSTRUCTED	obstructed	—
CLIPPED	clipped	—
UNMEASURABLE	unmeasurable	—
NO_WINDOW_FOCUS	noWindowFocus	—
NO_OUTPUT_DEVICE	noOutputDevice	—

NativeViewKeysjs · 18

Constant	Literal value	Official description
X	x	—
LEFT	left	—
Y	y	—
TOP	top	—
WIDTH	width	—
HEIGHT	height	—
AD_SESSION_ID	adSessionId	—
IS_FRIENDLY_OBSTRUCTION_FOR	isFriendlyObstructionFor	—
CLIPS_TO_BOUNDS	clipsToBounds	—
CHILD_VIEWS	childViews	—
END_X	endX	—
END_Y	endY	—
OBSTRUCTIONS	obstructions	—
OBSTRUCTION_CLASS	obstructionClass	—
OBSTRUCTION_PURPOSE	obstructionPurpose	—
OBSTRUCTION_REASON	obstructionReason	—
PIXELS	pixels	—
HAS_WINDOW_FOCUS	hasWindowFocus	—

MeasurementStateChangeSourcejs · 2

Enum for state change sources.

Constant	Literal value	Official description
CONTAINER	container	—
CREATIVE	creative	—

ElementMarkupjs · 1

Mark-up for DOM elements.

Constant	Literal value	Official description
OMID_ELEMENT_CLASS_NAME	omid-element	—

OMIDFriendlyObstructionTypeios · iOS OMIDFriendlyObstructionType · 4

List of allowed friendly obstruction purposes.

Constant	Literal value	Official description
OMIDFriendlyObstructionMediaControls		The friendly obstruction relates to interacting with a video (such as play/pause buttons).
OMIDFriendlyObstructionCloseAd		The friendly obstruction relates to closing an ad (such as a close button).
OMIDFriendlyObstructionNotVisible		The friendly obstruction is not visibly obstructing the ad but may seem so due to technical limitations.
OMIDFriendlyObstructionOther		The friendly obstruction is obstructing for any purpose not already described.

App & device state

AppStatejs · 2

Enum for state of the native app.

Constant	Literal value	Official description
BACKGROUNDED	backgrounded	—
FOREGROUNDED	foregrounded	—

DeviceLockStatejs · 2

Enum for device lock state of the native device.

Constant	Literal value	Official description
LOCKED	locked	—
UNLOCKED	unlocked	—

DeviceCategoryjs · 4

Enum for category of device OM SDK is running on.

Constant	Literal value	Official description
CTV	ctv	—
DESKTOP	desktop	—
MOBILE	mobile	—
OTHER	other	—

Deprecated and superseded values

AccessMode.DOMAIN = domain
DOMAIN access mode is no longer supported. Selecting DOMAIN access mode will result in LIMITED access mode being applied.
AdEventType.VIDEO = video
Superseded by value 'media'; OM SDK continues to support this value for backwards compatibility.
AdEventType.STATE_CHANGE = stateChange
This constant will be removed in a future release of OM SDK.
ErrorType.VIDEO = video
This type of error has been superseded by 'media'.