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Subly - Cody Patterson

I worry this news comes too late to be of much use, but I’m pleased to report that I have figured out how to provide captions that meet the 99.9% standard (including capitalization and punctuation!) without taking 6 x video length to do it or wanting to smash my head into a brick wall.


Here's a link to the product (don’t worry, it’s on my MediaFlo library and private):


Here's how I did it:


The first thing I tried was to upload the video to YouTube (as a private video, not public – probably not kosher, but I’ve deleted it now) for automatic captioning, then download the .vtt file, then download CADET (the free captioning software I told you about).  That didn’t work.  CADET, it turns out, is a huge and complicated download that comes with a lot of other sinister-looking stuff, and I didn’t want to go forward with a process that my colleagues wouldn’t have been comfortable trying.


Then I found Subly.  Subly is free right now (it looks like they are going to move to a freemium model soon) and allows you to upload a video, auto-captions it for you, and then provides a *very* easy interface in which you can edit the captions.  Once you’ve edited the captions, you can download an updated caption file (not .vtt, something else, I forget which type) as well as a fully processed captioned video.  By default this video will have the Subly brand mark in the upper right corner, but for now they’ve made it very easy to remove this.


The upside is that the editing process was FAST.  About 1.5 x video length, maybe.  It goes faster if you don’t talk constantly throughout your lecture (wait for students to answer questions), since there’s less text to edit.




  • Subly’s auto-captioning AI is just not as good as YouTube’s.  YouTube is actually *very* accurate except that it doesn’t seem to provide any punctuation or capitals at all (doesn’t even capitalize the word “I”).  On the other hand, YouTube puts a lot of redundancy into its captions, which makes them much harder to edit.  (By “redundancy” I mean you’ll have a caption like “it doesn’t seem to provide any punctuation or capitals at all” and then a separate caption like “any punctuation or capitals at all (doesn’t even capitalize the word “I”)”, and you have to edit both manually.)
  • No idea yet what the freemium model will look like or what it will cost.  Or if the service will remain online if they don’t get enough traction.
  • I don’t know yet whether there are limitations on video length.
  • There are a lot of processing steps that take time – not active attention, but time.  Auto-captioning takes time.  Reprocessing the video after you edit the captions takes time.  Publishing the video on MediaFlo takes time.  But this is likely to be true of any process that does this good a job.


However, this process seems to produce a professional-grade product that nobody in their right mind could object to.  I plan to use it at least for the videos I’m making for MATH 3330 that are more stable and public-facing (flipping videos, not in-class lectures with student names and images).  I’ll probably do it for my MATH 2472 lectures as well, since I have a deaf student there.


Let me know if you’d like more information or a demo.  If you wanted, I’m sure you could easily learn to use the tool on your own without assistance.