Q&A: Measuring Viewability

There are numerous performance metrics — including impressions, viewability, and interaction — that help advertisers evaluate the success of a campaign. For several years, advertisers have demanded more transparent solutions for measuring online video ad viewability — and rightfully so. In response, the IAB introduced the Open Measurement Software Development Kit (OM SDK) and Open Measurement Interface Definition (OMID) for Web and InApp. These solutions enable the entire industry to be more transparent. Together with our partners, smartclip is promoting the fastest possible implementation of OM SDK and OMID.

In addition to implementing these new IAB standards, smartclip has also set out to improve viewability measurement by adopting the Digital Video Ad Serving Template 4 (VAST 4). VAST 4 is a standardised file format for ad creatives and has no direct connection to the OM SDK and OMID. Nevertheless, it is important that the publisher’s player supports the VAST 4 format in order to achieve full transparency and a reliable viewability measurement.

To help publishers with this process, our expert Martin Voss, Head of Ad Verification & Analytics at smartclip Europe, answers the most important questions.

What is the Open Measurement SDK?

The OM SDK was developed in the efforts to standardise the ad measurement and verification by third-party suppliers. In order to facilitate streamlined access to the ad placement data that is collected, the OM SDK provides code that can be generally applied, along with libraries that are accessible to all.

What are the advantages of the Open Measurement SDK? 

The OM SDK enables advertisers to measure campaign metrics like viewability and invalid traffic (IVT) regardless of the publisher’s player or the enabled measurement service providers. Another advantage is that publishers no longer have to install multiple SDKs from different service providers. The OM SDK reduces overall complexity and allows for greater flexibility when it comes to working with multiple measurement service providers. Additionally, the setup saves resources as significantly less maintenance and coordination time is required. But most importantly, the new streamlined, uniform measurement standards give advertisers greater transparency.

What is the Open Measurement Interface Definition?

The OMID is an application programming interface (API) that receives all signals collected by sites and apps via the OM SDK. Measurement service providers place their scripts in the ad creative in order to transmit those signals to their own servers via the OMID. In short, the OMID enables the communication between the OM SDK in the publisher’s player and the service provider’s measurement script.

What are the advantages of the Open Measurement Interface Definition?

When the OMID is used, there is no need for Video Player-Ad Interface Definition (VPAID) wrappers. VPAID wrappers are known to be error-prone and unreliable. With the OMID, ad playback is more stable with fewer latencies, resulting in a better user experience and more reliable measurements.

What is VAST 4?

The VAST 4 is another IAB standard that is separate from OM SDK and OMID. VAST 4 determines the file format of the ad creative. Thanks to VAST 4, interactive ads can be delivered via the Secure Interactive Media Interface Definition (SIMID) instead of VPAID and can measure parameters including interaction and viewability. In contrast to VPAID, VAST 4 does not permit the ad creative to take control over the player. This characteristic of VPAID often leads to ad playback failures.

What are the advantages of VAST 4?

While the OM SDK can also work with VAST 2 and VAST 3, VAST 4 reduces the risk of invalid traffic (IVT) and facilitates a quicker ad supply. With VAST 4, the publisher retains control of the ad delivery, which leads to faster loading times, more accurate measurements, and fewer ad playback failures.

What needs to be implemented and taken into consideration by the different market participants?

Publishers need to implement the OM SDK for web and in-app measurements. 

Ad Networks need to integrate the OMID interface within the creative. 

Measurement service providers need to set up the measurement provider script and link this to the OMID interface within the creative. 

Page players need to support the OM SDK and the VAST standard (VAST 2 or higher – VAST 4 highly recommended).

Advertisers and agencies need to provide VAST-compliant advertising media (VAST2 or higher – VAST 4 highly recommended).