Roku Developer Program

Developers and content creators—a complete solution for growing an audience directly.
cancel
Showing results for 
Search instead for 
Did you mean: 
mkammes
Level 7

Defining captions (SMPTE-TT) with HLS VOD

Hello all:

This is slightly OT, but I'm looking for some guidance.

I have several dozen videos prepped as HLS VOD files. They do not have embedded captioning. As I have the SRT files (which I can convert to SMPTE-TT, etc.), my first thought is to make the sidecar files.

Reading through http://sdkdocs.roku.com/display/sdkdoc/ ... on+Support , it appears that the older SMPTE-TT format is my only alternative as a sidecar file, unless I want to re-transcode the files with the captioning files embedded into the stream.

The kernel of my channel is based off of the videoplayer example. My notion is to create an XML tag in my server hosted XML for the URL of the SMPTE-TT file, and then build an array for that in my showfeed.brs. Is that it?

Or, is it possible to define a sidecar SMPTE-TT file in the M3U8 HLS playlist...or is this just for embedded captions in the stream?

If I'm approaching this the wrong way - please let me know. It's not out of the realm of possibility to re-transcode the VOD files with the CC embedded, although that does limit future flexibility, and transcoders that can create HLS VOD with 3rd party caption files are a bit more rare.

Thanks!
0 Kudos
2 Replies
mkammes
Level 7

Re: Defining captions (SMPTE-TT) with HLS VOD

After a day and a half of research, and right after I posted this question in frustration, I stumbled across this and it works.

I'm not sure *why*, but it does, and it is really, really, *really* simple.

https://preonline.zendesk.com/hc/en-us/ ... u-Channels
0 Kudos
TheEndless
Level 7

Re: Defining captions (SMPTE-TT) with HLS VOD

"mkammes" wrote:
I'm not sure *why*, but it does, and it is really, really, *really* simple.

It works, because the videoplayer example was written long before the Roku supported TTML/DFXP. The name of the XML node is inconsequential (as long as it's named "srt"), because the code just parses that value and sets the SubtitleUrl content-metadata attribute.
My Channels: http://roku.permanence.com - Twitter: @TheEndlessDev
Instant Watch Browser (NetflixIWB), Aquarium Screensaver (AQUARIUM), Clever Clocks Screensaver (CLEVERCLOCKS), iTunes Podcasts (ITPC), My Channels (MYCHANNELS)
0 Kudos