What is Just-In-Time Packaging (JITP) and What Are Its Benefits?

Just-In-Time packaging generates packages based on the device requesting the content, automatically selecting appropriate stream packaging and DRM formats. Thus, JITP helps reduce lead times for launching new format and DRM with cost efficiency in storage and bandwidth. 

Delivering VOD content (Video-on-demand) for multiple devices using HTTP streaming can be done via HLS/DASH/MSS streaming formats. If these videos have to be delivered via CDN (Content Delivery Network), then the streaming service must store each VOD content in multiple formats for delivery to different devices. Instead, we can package the content “on the fly” or “just in time” based on clients’ requests, which has multiple benefits. This article explains the JITP mechanism and its benefits.

If you are new to video streaming, please read OTTVerse’s introduction to HTTP Live Streaming (HLS) and introduction to MPEG-DASH.

With that, let’s get started.

What Is Packaging?

Packaging is the process of preparing a video for delivery via HTTP streaming protocols, and it could be either live or VOD. Do read OTTVerse’s Fundamentals of ABR Packaging for VOD, Live – HLS, and MPEG-DASH to get an idea about packaging for video streaming.

Different Modes of Packaging

Linear Packaging

This packaging is mostly popular for delivering live content where latency is critical for G2G (glass-to-glass). In this type of packaging, live video is converted to a stream, for example, an MPEG-2 Transport Stream (TS), which is input for a packager.

The packager segments the streams into files and either push them to a CDN or stores them in the origin server so that CDN can pull from the origin either segments, chunks, or manifests as shown in the example below,

The output of the transcoder is a collection of H.264/AAC-LC encoded video/audio streams carried in a multi-bitrate (MBR) collection of MPEG-2 SPTS streams. The output of the packager is a collection of adaptive bitrate (ABR) HTTP streams delivered via a CDN.

File-based Packaging

File-based packaging is mostly used for VOD cases where pre-recorded encoded content is converted from one format into an HTTP deliverable format that can be multiple formats of HTTP (HLS / DASH / MSS). In this case, a file is converted and stored in 3 different formats in multiple bitrates (e.g. 4 bitrates). Thus a single content is available in (3 formats * 4 bitrates) = 12 times on the origin side, thus occupying storage of CDN.

In the example below, a TS file format suitable for legacy TS streamers into an HLS, DASH, and MSS segmented format. With offline packaging, all segments (and playlists) are created and stored for subsequent delivery.

Just-In-Time Packaging

JITP is most probably used for VOD kind of use cases for delivering the streams to the end-user. The packager converts the source file into desired renditions (different resolutions, different bitrates) and stores them in a format-agnostic state. JITP is different from traditional packaging, where different renditions are stored in a specific package like HLS, DASH, MSS, etc., but rather as fragmented MP4s (fMP4s). When a user requests content from any given device, then JITP (Just-In-Time Packager) server generated the appropriate packages dynamically based on the device requesting the content and doing JITE (Just-In-Time-Encryption) in multi-DRM formats.

Edge Packaging

Edge packaging is again mostly favored for live streaming delivery, wherein you want to reduce your core network bandwidth by reducing the hits to your central server. The packager is moved to an edge site co-located with CDN, and this packager will function the same as it used to do at the network’s core. 

Benefits of Just-In-Time Packaging.

Storage Cost Savings

When multiple HTTP streaming formats (HLS, DASH, MSS, etc.) are used, every asset must be stored in multiple formats, with associated storage costs. Since the packaging is done on the fly in real-time only when that content is requested by a viewer, saving tremendous storage and bandwidth costs. 

Future Proof of Assets

Applying packaging at the time of the user’s request allows operators to easily adopt new package types and DRM formats and updates to existing formats. In earlier scenarios, if a new version of packaging or DRM format was introduced, the entire library had to be re-transcoded to the new format and older formats. Using JITP, we only need to update the JITP server once to support the new format, and all the assets are instantly available to be used in the new format.

Future Proof Content to Regions

JITP packaging provides flexibility to control manifest at the time of playback. For example, consider a piece of content has to be launched in separate international regions by adding multiple audio tracks. The solution is straightforward with JITP. Without JITP, multiple tracks addition had immense post-production work and complexity. Now you can upload the video once with as many tracks as you need, and JITP can present the content dynamically based on the geography of the requesting devices.

Additional features 

With JITP, companies can harness personalized ad insertion, region-based dynamic ad insertion, and other delivery rules.

Conclusion

Just-In-Time packaging generates packages based on the device requesting the content, automatically selecting appropriate stream packaging and DRM formats. Thus, JITP helps reduce lead times for launching new format and DRM with cost efficiency in storage and bandwidth. 

References

• https://www.digitaltveurope.com/files/2012/05/RGB-Just-in-Time-Packaging1.pdf
• https://www.brightcove.com/en/resources/blog/why-you-need-just-time-packaging-dynamic-delivery/