Online video advertising is reportedly one of the fastest growing ad mediums. In US alone, digital video is expected to reach almost $9.59 billion in spendings this year, according to eMarketer.
In a series of blog posts we will test and compare several VAST implementations and document our finds. For the complete battery tests we highly recommend reading: part 2, part 3, part 4.
Interactions (between different parties) in the advertising ecosystem can be complex, therefore there is a need for standards to govern it. The W3C in the advertising space is IAB: The Interactive Advertising Bureau, responsible for setting standards and best practices for uniformity around online advertising.
One example is Video Ad Serving Template (VAST) specification. A universal XML schema for serving ads to digital video players. Briefly, it provides a common protocol that enables ad servers to use a single ad response format across multiple publishers/video players.
With the rapid growth of the online video advertising, new and improved specifications are released by IAB to accommodate the ever-changing industry demands. The current VAST version is 4. Similar to how browsers continuously release new versions to support the latest HTML/CSS features, so do video platforms, in order to remain competitive. They strive to implement the newly released IAB specs.
The discussion might be a bit technical and refer to various parts of the VAST XML schema. Therefore, before continuing, you might need to brush up on your knowledge of VAST 3.0.
VAST 3.0 template introduced the concept of Ad Pods. An Ad Pod enables a sequence of ad elements to play within a single Ad Break.
The number of devices, browsers, operating systems etc. makes it difficult to deliver a flawless web video experience for every user. Varrando aims to empower every publisher to deliver the same rate of video content engagement to individual visitors.
Even in 2016, several years after HTML5 video gained tremendous traction, and, is supported in major browsers, it is still not the de facto standard in delivering video to the web. In order to ensure cross browser video compatibility Flash fallback is used.
Flash and HTML5 are different technologies, each with its own capabilities and limitations. But, in the end, they complement each other regarding video playback. For example, FLV videos require Flash for playback, whereas MP4 videos can be played by both.
VAST Test I
Video players should ensure uniform UI and a smooth transition between different tech playbacks (tech playback = Flash or HTML5 player component that actually plays the video content or the video ads). This is an essential feature to have in various common use-cases like the following.
- Video player is playing MP4 content and pauses for an Ad Break
- Ad Break features an instance of an Ad Pod which contains both MP4 and FLV linear ads
- The first MP4 linear ad will use the same HTML5 playback
- The second FLV ad, however, will have to switch to Flash for playback
- Upon Ad Break completion the player will switch back to HTML5 to resume MP4 initial content
Now, let’s create a VAST test to showcase the playback switch. We will refer to it as VAST Test I. The VAST Inline response contains an Ad Pod with the following structure:
Ad sequence = 1: Inline Ad – FLV Media File (Flash only)
Ad sequence = 2: Inline Ad – MP4 Media File
Running VAST Test I for JW Player resulted in:
- Flash tech displays the ads
- HTML5 tech fails to load any ads and triggers an ad error
Running VAST Test I for Varrando Player resulted in:
- Ad Pod played correctly as Varrando switches to the right playback tech dynamically for each ad type.
VAST Test II
An ad can contain multiple Media File elements specifying multiple variations of the same Ad. Second test is similar to the first one but it returns 2 Media Files in the first Inline Ad response. A video player should select the Media File that it can run best.
Second test, called VAST Test II
Ad sequence = 1: Inline Ad – JS Vpaid Media File, MP4 Media File
Ad sequence = 2: Inline Ad – FLV Media File (Flash only)
Running VAST Test II for JW Player resulted in:
- Flash tech returns an ad error even if the second Media File of Ad 1 is MP4 format and can be displayed
- HTML5 tech fails to display the second ad from the Ad Pod on account of not switching dynamically to Flash (see first test)
Running VAST Test II for Varrando Player resulted in:
- Ad Pod played correctly as Varrando selects the ad Media File that it can run best