A comparison between traditional broadcast TV and streaming linear TV workflows

Slogans come and slogans go. If visitors pay any attention to a tagline on your site, at best they think, huh.” Then they move on with their lives.

So maybe we’d better explain what we mean by streaming meets linear TV.” Which tops the solution page for our new Unified Virtual Channel.

The streaming part of the equation is easy to understand. Nearly everyone on Earth has streamed a video, unless they’ve been living in a fascinating little village without mobile phones or internet.

But what do we mean by streaming meeting” linear TV?

First off, it’s a core part of our mission. (Which makes defining the phrase pretty important, at least to us.)

Bridging the separate worlds of streaming and linear TV, getting video streaming to reach parity with broadcast, is what we’ve been after since the founding of Unified Streaming (our early days of Smooth Streaming and Adobe Flash).

Building solutions, optimizing them, solving complex challenges in video, conducting research, partnering with other like-minded companies with ambition, and developing standards and specifications: these actions have all contributed toward our mission. (Which, frankly, is not yet complete, and, even more frankly, seems never-ending.)

And what do we mean by linear TV”?

Well, linear TV is just another way of saying the TV type that dominated broadcasting for decades. Before the streaming age dawned, linear TV was the only way to deliver televised entertainment. Linear TV was, and still is, programmed, encoded, and broadcast via satellite or cable channels from purpose-built playout facilities, and enjoyed mostly on television sets, with fixed viewing times.

Before Friends” gained legions of younger fans on Netflix, the 90s hit show certainly started out in the coveted Thursday night primetime slot on linear TV.

Now for the meeting” part. How can Unified Streaming reasonably say that its virtual channel solution marries the qualities of linear TV to the qualities of streaming?

Fine question.

Let’s look at some diagrams, because they can easily draw out the differences between linear TV and streaming TV.

Live linear channel w/​traditional broadcast + OTT

Figure 1 shows the routes that a live linear channel and an OTT (internet-only) channel take. And you can see that the two paths to the end user (the viewer) diverge.

Let’s break down the live linear channel, everyone’s true-blue method for consuming TV. As a CMS (Content or Channel Management System) sends a playlist to the playout device, a MAM (Media Asset Management) system sends media, too. From there, the playlist and media trundle on over to the broadcast encoder. After being encoded, the content shuttles through the typical TV distribution process to cable platforms and expensive uplinking to satellite for further distribution. 

The OTT channel takes a different trip after playout. The content goes next to an OTT encoder, then to a packager, and then it ships to a CDN (Content Distribution Network). Finally, a player displays the content for the human being who watches it half-heartedly, while glaring at a secondary screen. (Let’s face facts: we’re all distracted these days, for various reasons.)

There are advantages to the traditional method of broadcast delivery. You may already have the infrastructure in place, with spare capacity, so you can easily create new services and manage synced linear and OTT workflows simultaneously. Encoders offer the most adaptable approach to media handling, and are part of the traditional model, and likewise, so are full, advanced graphic capabilities like lower thirds, squeezes, and logos.

But there are downsides, too. Of all the solutions, the traditional broadcast plus OTT model costs the most. Upfront, you’ll invest tens of thousands for a full playout- and encoder-based workflow. And if you don’t have spare capacity, your time-to-market could be weeks instead of days/​hours. The delay could challenge your need to stay flexible and on trend. Also, if the channel isn’t a hit with viewers, you’ve wasted effort and cost. Having to run two separate distribution methods — IP for OTT and cable/​satellite for traditional TV — is also somewhat of a nuisance. 

Broadcast is a push-based method of airing content, meaning there’s a constant flow of traffic. The workflow is always on,’ which costs money and carbon. 

OTT-only channel

Here is that same OTT-only delivery route, separated from the traditional TV one, in Figure 2 above.

Pros of this approach include flexibility of content preparation, and basic graphics capabilities, like a channel logo.

Cons of the process include costs such as an expensive encoder, and high compute usage for media processing. Compared to a playout system, most encoders don’t have as full of a feature set. Graphics are limited.

Now, let’s see what the journey looks like for an OTT-only virtual channel.

OTT-only virtual channel


As you can see, in Figure 3 (VOD2Live workflow), instead of a MAM, an OTT VOD (video on demand) archive stores content. Here the difference is that the media is pre-encoded. Which means the step that is removed, of course, is the OTT encoder. The playlist with pre-encoded media goes straight to the packager (in our case, Unified Origin), and then so on: to the CDN, and then to the player.

In the OTT-only virtual channel, you can skip the expensive encoder, and reuse media prepared for transmission. The JIT (just-in-time) packager extends your capabilities: now you can update media and DRM keys.

But with this model, you have no real way of doing graphics, and content must be encoded with matching profiles.

Manifest manipulation virtual channel

A virtual channel can also contain in its process, from media source to player, manifest manipulation, as you can see in Figure 4. These sources can be any OTT stream: VOD content, or live. This stream, already available as DASH and/​or HLS, speeds to a CDN, which then sends it to a manifest manipulator, then to the player.

Advantage-wise, the manifest manipulation method makes use of existing caches and boasts a low infrastructure cost. Its startup time is speedy, and since its media is already available on the CDN, it references existing media segments. There is no extra cost for CDN ingest or storage.

But DRM (Digital Rights Management) on the player is difficult, and the features depend heavily on the intelligence of the manifest manipulator. Some features are available only for HLS. If you want the ability to change media, then you would need to use a JIT packager (e.g., Unified Origin) for the input, but this also breaks your caching. Also, content must be encoded with matching profiles, and sorry — no graphics.

Unified Virtual Channel

Dynamic transitioning between playlists, in less than 20 seconds, is possible with Unified Virtual Channel. The solution repurposes VOD content and handles live input sources, too, reusing the same media segments for live sources. Do you want flexibility to update media and DRM on the fly? Unified Virtual Channel’s got it. And it’s a low-cost solution because there’s no encoder.

Since it’s a pull-based approach, the channel starts running only when viewers start watching, making it a truly green approach. What’s better for the environment than using compute power once your viewers tune in to your service, and never before? To discover the types of channels you can create as well as additional benefits, see its solution page.

Cons include the necessity of content being encoded with matching profiles. And just like other OTT-only solutions, graphics are not included.

So … what do we mean?

Ultimately, what we mean by streaming meets linear TV” is you no longer need to be confined to traditional encoder-based workflows.

OTT-only streaming quality and technical capabilities are now on par with broadcast. In some cases, they exceed limitations that hamstring the traditional approach today. With the options to combine VOD and Live sources as well as dynamic seamless transitioning, our new Unified Virtual Channel solution comes the closest to a real alternative to traditional workflows. 

Consider airing a low-latency, live football match, then a pre-taped TV show. Intersperse the content with ads (made possible with SCTE 35 markers and your preferred third-party ad vendor), and you’re mimicking linear TV, only it’s streamed over the internet. All that’s possible with Unified Virtual Channel.

Boasting the best codecs, and efficient repurposing of pre-encoded media, a virtual channel not just dupes the lean-back experience of linear TV. It beats linear TV in so many ways, because it can do so much more.

For instance, it can do FAST (free ad-supported TV) channels, which easily monetize new and archived content. Unified Virtual Channel can also do sports channels, or any live event channels, and regional channels, which cater programming to particular geographic areas.

But we’ll get into all that in upcoming blogs about the benefits of virtual channels.

Curious about Unified Virtual Channel? The solution is currently in private beta, so it’s not yet included in our images or packages. Contact Linzi McRae if you’re interested in joining the private beta program. Public release is planned for Q1 2023.