This guide outlines some best practices for implementing [in-stream ads](https://support.google.com/authorizedbuyers/answer/2961301). ## Creative review process Video ads must pass Authorized Buyers's standard verification checks before they are served by real-time bidding (RTB). After approval, RTB starts and continues to serve them until they are disapproved. Note that video tags should remain live for the entire duration of the review. If the video tags are not live or become stale for any reason, they may be disapproved, post-filtered, and/or throttled. ## Key performance metrics Authorized Buyers uses the following metrics to measure video ad health. It's important to understand what these mean when assessing performance issues like latency and filtering. - View rate For video ads, view rate is the rate at which an ad is correctly served and rendered. View rate = Number of times the first frame is rendered / Number of times the ad won an auction - Error rate Common errors include: - Corrupted media file - File not found - Malformed VAST - Timeout Error rate = Number of errors / Number of won impressions - Dropoff rate The percentage of won auctions that don't get viewed because of user action or publisher player error. - Abandonment rate The percentage of users who start to view a video ad but do not finish viewing the ad---for example, they navigate away from the site or close the browser. A high abandonment rate is reflective of poor audience reception, due to low quality video ads or incorrect audience targeting. - Skip rate The percentage of users who skip viewing a video ad. Note that: View rate + dropoff rate + error rate = 100%
And for: - Skippables ads View rate + skip rate + abandonment rate = 100% - Standard in-stream ads View rate + abandonment rate = 100% ## Video ad throttling Video ad throttling prevents problematic video ads with low view rates and high error rates from competing in the auction. Authorized Buyers uses view rate and error rate to determine how well a video ad is being served. Authorized Buyers throttles a video ad by limiting the total number of auctions it can win per hour to twelve. ### Why is throttling used? Video ad throttling helps keep the exchange running smoothly because even if a buyer wins an impression but the buyer's video ad is not shown, the buyer is not charged for the impression. Authorized Buyers's video ad throttling ensures that video ads with fewer errors and higher view rates serve more often than problematic video ads, which benefits both publishers and buyers. ### Reduce throttling To ensure that a video ad is not throttled, make sure the video tag is functional and is not returning errors. Check the **Filtered Bids** section in the **Bidding** tab of your [RTB Dashboard](https://www.google.com/authorizedbuyers/). Look for the video creative "throttled" reason listed in the Google filtered bids section. Click **Details** to see a breakdown by creative ID or publisher domain. ## Video ad filtering Video ads must meet the video ad slot requirements passed in the bid request. When a buyer responds to a video bid request with a video tag that does not meet those requirements, the buyer's response is filtered. For example, if a bid request requires a skippable video and a buyer responds with a non-skippable video ad, that response will be filtered from the auction because the video ad is ineligible to serve in the publisher player. Authorized Buyers honors publisher settings to foster good user experience. ### Why are video ads filtered? To find out why a video ad is filtered, look up the [creative status codes](https://storage.googleapis.com/adx-rtb-dictionaries/creative-status-codes.txt) dictionary file for the filtering reasons. For example, video ads can be filtered for the these reasons: - Missing MP4 video file - Ad duration longer than requested - Ad duration shorter than requested - Skippable ad on a non-skippable request - Non-skippable ad on a skippable request ### Reduce filtering To reduce filtering of video ads: - Make sure your bidder is paying attention to the video portion of the bid request and responds with only ads that match the request. - Check the **Filtered Bids** section in the **Bidding** tab of your [RTB Dashboard](https://www.google.com/authorizedbuyers/). Look for the video creative "filtered" reason listed in the Google filtered bids section. Click **Details** to see a breakdown by creative ID or publisher domain. > [!IMPORTANT] > **Important**: Changing the characteristics (skippable, non-skippable, VPAID, or non-VPAID) of a video ad without changing its creative ID will result in filtering of the ad, so it's best to avoid it. ## Ensure delivery The following guidelines help buyers to ensure smooth delivery of their video ads: - [In-stream video ad technical specifications](https://support.google.com/authorizedbuyers/answer/6045575) To be eligible to serve on all types of inventory, video tags must contain the MP4 MIME type. If the MIME type is missing, the video ads can be filtered, throttled, or both. - [Skippable compliance](https://developers.google.com/authorized-buyers/rtb/skippable-guide) Make sure your 15s or 30s skippable ads have the skip offset after 5 seconds. You can determine whether inventory is skipable with the `BidRequest.imp.video.skip`. - Duration compliance Bidders should read the minimum and maximum ad duration fields and respond accordingly. - HTML5 compliance Authorized Buyers and Ad Manager publishers (both SDK and VPAID adapters) are migrating to HTML5 as the number of callouts that accept Flash (including VPAID Flash) continues to drop. Refer to the `BidRequest.imp.video.mimes` signal for what's accepted. - SSL On desktop, many publishers use SSL for logged-in users, which means that a very valuable set of users is now only accessible with SSL creatives. Thus buyers should have at least some SSL compliant creatives. ## Troubleshooting resources To ensure your video campaigns run smoothly: 1. Make sure your video creatives comply with the Authorized Buyers [technical specifications](https://support.google.com/authorizedbuyers/answer/6045575). 2. Check your pretargeting setup to make sure it is configured for the type of inventory you want to receive. 3. After your campaigns are live, check that all creatives are approved and are functioning properly. Use the following resources to troubleshoot any [filtered](https://developers.google.com/authorized-buyers/rtb/video_best_practices#video-ad-filtering) or [throttled](https://developers.google.com/authorized-buyers/rtb/video_best_practices#video-ad-throttling) video ads: - RTB Protocol [Get Started](https://developers.google.com/authorized-buyers/apis/start) guide - [`creatives`](https://developers.google.com/authorized-buyers/apis/guides/rtb-api/creatives) resource - [RTB Dashboard](https://www.google.com/authorizedbuyers/) - [Real-time feedback](https://developers.google.com/authorized-buyers/rtb/request-guide#realtime-feedback) - [Video Suite Inspector](https://developers.google.com/interactive-media-ads/docs/vastinspector_dual)