VAST and End Cards

VAST is an IAB standard that structures ad tags for video player delivery and uses an XML schema to transfer necessary metadata from the ad server to the video player. Additionally, VAST standardizes in-stream video ad serving and linear videos, such as in-app, full-screen interstitial videos as specified by the IAB. The following steps describe the VAST process.

1. The video player pre-fetches the ad request.

2. The ad server returns an XML ad response, which contains:

   • VAST version.

   • Impression tracking pixel.

   • Video duration.

   • Click tracking pixel.

   • Click-through URL.

   • Quartile-event tracking pixels fire at video start, 1st quartile, 2nd quartile, 3rd quartile, and video completion.

   • URL to video media files.

   • CompanionAd height, width, and assets.

The VAST response does not include any information on the placement or timing of video elements. To see the video player elements, see DT SDK Video Player.

1. A VAST ad markup is either INLINE, which contains all the elements necessary to display the video, or VAST Wrapper, which points to a downstream VAST document requested by another ad server.

2. A single click-through on the ad is expected, but multiple named click-tracking URIs (CustomClick) allow per-publisher customization. In addition, separate URIs can be provided for tracking the (CustomClickTracking) and for the destination page to open upon a click-through (ClickThrough).

3. The video player reports the quartile tracking URLs.

4. The ad server(s) record the impressions.

VAST Versions Supported by DT

• DT accepts VAST 2.0 and higher.

• DT supports some VAST 3.0 and VAST 4.x tracking event elements, including:

  • Fullscreen: The user activated a control to extend the video player to the edges of the viewer’s screen.

  • Expand: The user activated a control to expand the creative.

  • Exitfullscreen: The user activated the control to reduce the video player size to its original dimensions.

  • Collapse: The user activated a control to reduce the creative to its original dimensions..

  • Closelinear: The user clicked the close button on the creative.

  • Progress: (iOS only) The creative played for a duration at normal speed that is equal to or greater than the value provided in an additional attribute for offset, starting from SDK 8.2.3.

  • CompanionClickTracking: Available for both VAST wrappers and inline formats. For more information, see Companion Click Events.

  • The DT SDK manages firing the VAST tracking pixels and rendering video playback.

• VAST 2.0 is not entirely backward compatible with VAST 1.0

• Events are only relevant for the use case where the video starts in a non-full-screen mode.

The following table details the VAST wrapper handling capabilities.

When VAST 2.0 is supported and a bid request contains video.protocol:5 , DT provides the following VAST handling capabilities:

Number of VAST Wrappers Supported	Video MIME Types	VAST Filter Types	Video Ad Sizes
5 or less	Android: mp4, webM, 3gpp	Android: mp4, webM, 3gpp	Portrait (Vertical) Ad Formats: 320x480, 480x320, 768x1024

When VAST 3.0 is supported and a bid request contains video.protocol:6 , DT provides the following VAST handling capabilities:

Number of Wrappers	Video MIME Types	VAST Filter Types	VAST Video Ad Sizes
5 or less. DT discards ads with more than 5 wrappers.	iOS: mp4, m4v, Quicktime, 3gp2, 3gpp2, 3gp4, 3gpp4, application/javascript	iOS: QuickTime, mp4, m4v, 3gpp, 3gpp2, x-m4v, 3gp2, 3gp4, 3gpp4	Landscape Ad Formats: 1024x768

When VAST 3.0 wrapper is supported and a bid request contains video.protocol:8 , DT provides the following VAST handling capabilities:

Number of Wrappers	Video MIME Types	VAST Filter Types	VAST Video Ad Sizes
DT recommends using as few wrappers as possible.	Flash and .mov are not supported.

Video Media File Size Limits

SPECIFICATION	REQUIREMENTS
Optimal Performance	DT recommends running video file sizes under 3MB.
Bitrate	Maximum bitrate of 5000kbps. Preferred max bit rate is up to 2000kbps. Videos above 5000kbps are discarded.
Video Duration	Maximum duration of 30s.
Timeout	If DT cannot retrieve the video file within approximately 10 seconds, the video times out.
Aspect Ratios	The DT SDK runs videos with any aspect ratio; no constraints affect the aspect ratio. But recommends the following video aspect ratios: - 16:9 (for interstitial phone and tablet) - 4:3 (for iPad), 3:2, or 16:10 (Video Asset Algorithm).

Video Asset Algorithm

DT employs an algorithm for prioritizing media files passed within the VAST tag.

The prioritization is determined based on the following criteria:

SPECIFICATION	REQUIREMENTS
Bitrate	Media files that do not exceed the maximum bitrate have priority.
File Type	The file types considered for prioritization include MP4, 3GPP, and WebM. The order of file type preference is applied to Android and, similarly, to iOS based on their supported MIME types. DT respects the MIME types passed under the video object.
Aspect Ratio Alignment	Video files with an aspect ratio matching the best screen size have preference.

This algorithm helps ensure efficient and effective handling of media files within the VAST tag, prioritizing based on bitrate, file type, and aspect ratio alignment.

Tracking Click Events on VAST

DT enriches the TrackingEvents object with the DT click tracking URL and fires the click when the user taps the call-to-action (CTA) button or a video without a CTA button. The video pauses if the user leaves the app and returns to it.

DT SDK Video Player

The following sections provide an overview of the features related to the DT video player.

Sound

The sound icon is always available for users to toggle and appears on the upper left of the user's screen. DT supports the device sound settings. If the device is on mute, the ad plays with sound off; otherwise, it plays with the sound on. Publishers can override sound settings per user session.

Skip

For non-rewarded videos that are 15 seconds or less in duration are not skippable. No Skip button appears, and DT attempts to show the end card immediately after video completion.

For non-rewarded videos that are longer than 15 seconds in duration, a Skip button appears in the upper right corner after 5 seconds. DT attempts to show the end card immediately after video completion.

Countdown Timer

A countdown timer displays at the bottom left corner based on the video duration specified in the VAST XML.

Call To Action

The default text on the Call to Action button is Install Now. When the system detects the app store as a landing page, the text on the Call to Action button is Download.

Video Close Behavior

Tapping the Close (X) button on the video end card returns the user to the app and resumes gameplay. Clicking the CTA button during video playback takes the user to the DSP landing page (app store, in-app browser, deep link). After closing the landing page, the video resumes on the Skip and Close logic.

End Card Behavior

Appears after video completion or when the user skips the video. The Close button (X) button on the end card appears after 5 seconds. If no DSP-provided end card is available or if it fails to load, DT displays a default end card.

End Cards (CompanionAds)

CompanionAds commonly appear alongside or after video content. End cards appear when the user completes or closes the video and may be interactive. End cards often have a call-to-action for the user. DT recommends using end cards with all video types to improve performance. For Playable End Cards, we recommend a maximum size of 2MB.

The following table describes DT criteria for identifying End Card support in bid requests and shows specifications for implementing End Cards with video ads.

If any of the values [1, 2, 3] are present in the bid request, the following end card types are supported:

END CARD MIME TYPES	END CARDS AD SIZES	SORTING AND SELECTING THE COMPANIONAD ASSET ALGORITHM BASED ON
JPEG	320×480	Orientation (closest match to the video media file orientation).

If video.ext.mraidendcard is set to 1 in the bid request, the following end card types are supported:

END CARD MIME TYPES	END CARDS AD SIZES	SORTING AND SELECTING THE COMPANIONAD ASSET ALGORITHM BASED ON
GIF	480×320	Ad Size (closest match to the device height and width).
Static	1024×768	Resource Type (HTML, iFrame, Static).
HTML	768×1024
iFrame	Minimum ad size is 300x250.
PNG	No maximum size, but static end cards larger than the screen are scaled down and centered.
MRAID 2.0 and MRAID Playables	HTML and iFrame end cards should not exceed the height and width passed in the bid request.

Other CompanionAd Criteria

• If one media file fails to load, DT proceeds to the next one in the sequence. If no ad loads, DT tracks the error internally.

• If no valid end card appears, DT blurs the last video frame and overlays a default end card with a CTA button.

• After receiving the ad markup in the bid response, DT fetches the end card immediately after the video finishes playing.

• CompanionAds and end cards do not apply to Native Ads.

Digital Turbine Default End Cards

DT pauses on the last frame of the video and adds a green call-to-action button with "Install Now" text.

Video End Card Close Behavior and Custom Close

• Five seconds after a video end-card appears, the close button (X) appears in the upper right-hand corner.

• There is no countdown on the end-card x-button.

• If a DSP provides its own MRAID end card, and uses ()useCustomClose, DT adds a fail-safe X button on the video end card which appears after 15 seconds.

Companion Click Events and CompanionClickTracking

• The DT Exchange SDK handles the CompanionClickThrough when a user clicks the end card.

• DT supports CompanionClickTracking, a VAST 3.0 component, for VAST wrappers and VAST inline ads.

Video Click Tracking Enhancements

Understanding user engagement in real time is critical for creative optimization. DT supports the following substitution macros to add to your click tracking URLs for ClickTracking and CompanionClickTracking.

• [ADPLAYHEAD]: Macro passes a value in HH:MM:SS.mmm format, indicating the time the video ad played before the user clicked on the VAST CTA or Skip button.

• [CLICKAREA]: Macro passes a string value describing where the user clicks on the VAST ad:

  • CTA: The user clicks on the CTA button on the video player.

  • COMPANION: The user clicks on the companion/end card.