What is Ad Stitching? Complete Guide to Server-Side Ad Insertion Technology

Watching shows and movies online is more popular than ever. However, for streaming services to continue developing, they need to generate revenue from ads. One of the most effective ways to achieve this is through a technology known as ad stitching, also referred to as server-side ad insertion (SSAI). This OTTclouds article will explain what ad stitching is, how it works, and why it’s important for streaming platforms, advertisers, and viewers. This technology enables streaming services to display ads smoothly and in high quality, providing viewers with a better experience.

How streaming television evolution

Streaming TV has changed in a big way. More people are watching shows online than ever before. In the U.S., streaming accounts for almost half of all TV viewing, surpassing cable and traditional broadcast TV. As a result, streaming services are generating more revenue from ads, and they need innovative new ways to integrate those ads into their videos.

Moreover, the market for streaming ads is growing very fast. For example, ad spending on smart TVs is expected to reach $41.8 billion by 2025 and is projected to continue rising by 2029. Due to this growth, ad stitching has become a crucial tool for streaming platforms to retain viewers while generating additional revenue from ads.

What is Ad Stitching?

Ad stitching refers to the technology that dynamically inserts advertisements into video content streams at the server level before delivery to viewers’ devices. Unlike traditional client-side methods, where ads are loaded separately on user devices, ad stitching combines video content and advertisements into a single, seamless stream during the server-side processing phase.

In simple terms, ad stitching is a method of inserting ads into video streams before they reach your device. Instead of loading ads separately on your phone or TV, the ads and the show are combined into a single, seamless stream by the streaming service’s servers. This makes the whole experience feel more like watching traditional TV.

This technology is sometimes called server-side ad insertion (SSAI) or dynamic ad insertion. It’s become increasingly important because people watch videos on a wide range of devices, and streaming services want ads to look good and play smoothly across all platforms.

How Ad Stitching Works

Ad stitching involves several key technical processes that ensure ads are inserted seamlessly into video streams. Here’s a step-by-step breakdown:

• Ad Decisioning: When a user starts watching a show, the streaming service’s computer (the server) identifies available ad slots, selects the most relevant ads based on viewer data and targeting criteria, and prepares to display the video.
• Stream Assembly: The server combines the video stream, stitching together the main content and selected ads into a single, continuous stream.
• Delivery: The stitched stream is delivered to the viewer’s device, appearing as a single, uninterrupted video.

Technology Stack Components

• Content Delivery Networks (CDNs): CDNs cache and deliver the stitched streams efficiently to viewers worldwide.
• Ad Servers and Demand-Side Platforms: These platforms manage ad inventory, targeting, and delivery.
• Stitching Services: Our specialized services handle the actual stitching process, ensuring seamless transitions between content and ads.

This architecture enables real-time ad insertion, making it ideal for both live and on-demand streaming.

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CSAI vs SSAI: Complete Technology Comparison

Understanding the differences between client-side ad insertion (CSAI) and server-side ad insertion (SSAI) is crucial for choosing the right ad insertion method for your streaming platform. Each approach offers advantages and faces specific limitations that impact overall user experience and business outcomes.

Advantages of CSAI:

• Flexibility: Easier to implement for web-based content.
• Detailed Analytics: Provides granular data at the device level.

Advantages of SSAI:

• Ad Blocker resistance: Bypasses most ad blockers.
• Seamless experience: No buffering between content and ads.
• Cross-device consistency: Delivers a uniform experience across all devices.

Benefits of Ad Stitching Technology

Ad stitching is great for both streaming platforms and advertisers. It changes how ads work online by making them smoother and more reliable.

For Streaming Platforms:

• Ads are hard to block. Even as more young people use ad blockers, ad stitching still allows platforms to show ads and generate revenue.
• No buffering or poor quality. Viewers don’t have to deal with ads that slow down or ruin the video. In fact, 78% of viewers say bad ads make their experience worse.
• Better analytics. Platforms receive clear information about how ads are performing, not just on one device, but across all devices. This enables them to work more effectively with advertisers and generate increased revenue.

For Advertisers:

• Ads always get through. Regardless of the device or ad blocker viewers use, ads are delivered smoothly.
• Younger viewers see ads. Over 20% of people ages 18-34 always use ad blockers, but ad stitching still gets ads to them.
• Same experience on every device. Ads look and work the same on phones, tablets, smart TVs, and computers.
• Better targeting. Ads can be personalized for each viewer, utilizing smart technology to match their preferences and viewing habits.

Implementation Challenges and Solutions

While ad stitching has many benefits, it also presents some challenges to making it work effectively.

Technical Challenges:

• Speed matters. Live streams need to be fast, so ads must be added quickly to avoid delays. Placing ad servers closer to viewers and utilizing more advanced technology helps.
• Ads must fit the video. Ads should look and sound just like the show. If they don’t, viewers notice and remember less. Tools that match video quality help.
• Interactive ads can be tricky. Some interactive ads don’t work well with ad stitching yet, but new standards are making this easier.

Business Challenges:

• It takes money and tech know-how. Setting up ad stitching requires reliable servers and skilled personnel.
• Choosing the right partner is essential. Companies need to select reliable tech providers and closely monitor their performance.

OTT and CTV Applications

OTT (over-the-top) and connected TV (CTV) are the biggest reasons ad stitching is growing so fast.

OTT is booming. In 2024, 63% of U.S. households used ad-supported streaming services, up from 17% in 2022. Ad spending is rising rapidly, and major OTT platforms like Netflix, Amazon Prime, and Disney+ utilize advanced ad stitching techniques. Netflix is a great example, with its ad-supported plan growing from 40 million to over 94 million users in just one year, thanks to smooth ad stitching.

Connected TV needs special care. Smart TVs and streaming devices have different tech, so ad stitching must work on all of them. Ad spending on CTV is substantial and continues to grow.

There are some tech challenges. Ad stitching must work with different streaming formats, security systems, and subtitle options. Using fast, modern technology helps keep everything running smoothly.

Conclusion

Ad stitching has changed streaming advertising for the better. It makes ads look smooth and keeps viewers engaged, while also helping advertisers reach a wider audience. As streaming increases, especially on smart TVs, where ad spending is expected to reach $66 billion by 2029, using server-side ad insertion is now a must for any streaming service.

As more viewers use ad blockers, ad stitching becomes even more valuable. It prevents ads from being blocked, ensures ads display well on every device, and maintains a smooth viewing experience.

If you’re ready to get started or want to upgrade your ad stitching, working with experts at OTTclouds can help. We offer proven solutions and support every step of the way. The streaming world is evolving rapidly, so getting ahead with ad stitching now is a strategic move for long-term success.