How Cablecast and MediaScribe Narrate Work Together
This Article Applies To
Cablecast users with a MediaScribe Narrate subscription
Stations producing video on demand for Internet Channels or OTT apps
Government and community media stations working toward WCAG 2.1 AA compliance
What Is MediaScribe Narrate?
MediaScribe Narrate is an AI-powered audio description service from Tightrope Media Systems. It automatically generates spoken descriptions of key visual elements in your pre-recorded video — things like on-screen graphics, slides, and speaker actions — so that viewers who are blind or have low vision can follow along with the full content of your programming.
Audio descriptions are different from closed captions. Captions convert spoken dialogue to text. Audio descriptions narrate visual information that isn't conveyed through dialogue, such as a presenter pointing to a budget chart on screen.
Under ADA Title II and WCAG 2.1 AA, audio descriptions are required for pre-recorded video content published by state and local government agencies. The Cablecast and MediaScribe Narrate integration is designed to fit into your existing workflow with minimal extra steps.
Note: MediaScribe Narrate is a separate subscription from Cablecast. To get started, contact the MediaScribe sales team.
How the Integration Works
The integration is built around a Cablecast feature called Audio Sidecars. An audio sidecar is an additional audio track that can be attached to a VOD in Cablecast. When you request an audio description through the MediaScribe Narrate integration, Cablecast automatically uploads your VOD to Narrate, processes the audio description, and — once you've reviewed and rendered it in MediaScribe — downloads the finished track and attaches it to your VOD.
The result is an accessible version of your video that viewers can switch to directly from your Internet Channel or OTT app player — no separate file or manual upload required.
Requesting an Audio Description
Audio descriptions are requested from the Show Record, not from the MediaScribe platform directly.
Open the Show Record for the program you want to add audio description to.
Go to the Internet Video tab.
Scroll to the Audio Sidecars section below the TRMS Video On Demand section.
Find the MediaScribe Audio Description card and toggle Enable generation on.
Save the Show Record.
Once you save, Cablecast uploads the full VOD file to MediaScribe Narrate, and the job begins processing automatically. Cablecast uses the VOD file — not the original asset — because the VOD represents the final, trimmed version of the show that viewers will actually watch.
Note: The Audio Sidecars section also includes an Add Sidecar option for manually attaching an audio file from any provider (MP3, WAV, MP4, or OGG, up to 50MB). The MediaScribe Audio Description card is the one-click option for requesting AI-generated audio descriptions specifically.
Reviewing and Rendering in MediaScribe Narrate
While Narrate is processing, you can head to the MediaScribe Narrate platform to monitor progress. Your show will appear there shortly after the job is submitted from Cablecast.
Once processing is complete, the show will be in a Ready to Review stage. At that point, you can:
Review the AI-generated description events on a visual timeline.
Play any event to hear the description in context.
Edit any event that needs adjustment — for example, correcting a local official's name or a street name that wasn't recognized accurately.
Delete events that aren't needed, or add new ones at any point in the video.
When you're satisfied, click Render to generate the final audio description track.
Note: Rendering locks the project for future edits. You can unlock it after rendering, but reprocessing fees may apply.
For a full walkthrough of the review and render process, see Using MediaScribe Narrate in the MediaScribe support documentation.
How It Appears in Cablecast
After rendering is complete in MediaScribe, Cablecast automatically downloads the audio description track and attaches it to the VOD. You don't need to do anything additional in Cablecast.
Once attached, the audio description track is available anywhere that VOD is served. On your Internet Channel or public site, shows with an audio description display an AD icon, so viewers know the accessible version is available. When a viewer opens the VOD and starts watching, they'll see a headphone icon in the player that lets them switch between the standard audio and the audio description track.
