1 Reply Latest reply on Aug 14, 2018 7:36 AM by Stan Jones

    Help understanding Sidecar Closed Caption function

    davidb50848295 Level 1

      Hello! I'm trying to understand precisely how this sidecar business works.  My question is very specific:


      If I've lined up the CC on the timeline correctly and the video is 23.976fps, AND I want to make a sidecar .scc, will that work?  All I'm seeing as far as frame rate options go for .scc is 29.97.  This may be a stupid question but will that create a sidecar file that is no longer matched properly to video?  If I'm exporting video at 23.976 do I have to go with a .srt, .xml, or .mcc file type?  If so, is there a workaround?  Many VoD platforms restrict what closed caption filetypes they'll accept and most prefer .scc.


      Follow up question: since .srt is timed in milliseconds, is it always a safe bet to just make .srt sidecars wherever .srt is accepted? That way I don't have to worry about matching frame rate?


      A bit of background in case the question is confusing: I get closed captioning done through REV and we use that closed captioning for different lengths of video.  For instance, some distributors will allow us to include company branded bumpers at the beginning and end of the video and some do not. Rather than get closed captioning done for content with AND without the bumpers, I just clip off the ends of the caption file for content that can't include company branded bumpers.  Often the closed caption files I put on the timeline are .srt however it can vary between .srt, .mcc, and .scc depending on which one is most accurate/less work to include.


      I've been doing sidecars for about two months or so now and as far as I know, what I'm doing works. But I don't understand the how or why of it.  I'd rather not continue relying on an educated guess and be able to really understand this.


      Thanks for any help with this.  I've done two hours of research before posting and I haven't found anything addressing this question.  Guess it's too niche for the interwebz at large.

        • 1. Re: Help understanding Sidecar Closed Caption function
          Stan Jones Adobe Community Professional & MVP

          Sorry you didn't get any responses. I was hoping someone knew the answers, and we'd both learn something. Bottom line: I don't know the answer to your question.


          Yes, .srt export for open caption is locked to milliseconds with no framerate, but you can certainly get sync problems if the original and final framerates aren't the same. As  you note, some other stream variations (.mcc; ebu) have many more fps options. But, despite its popularity, not .scc. (Because it was originally DVD that actually used 29.97 even for 23.976?)


          In any event, even where the whole workflow is set to 23.976, you can get sync issues. See this thread and the link I provided there:


          Re: Converting open captions to closed or exporting as .stl


          Let us know what you come up with!