Josh Barratt's Blog

A collection of uploaded thoughts

Screencasting Presentations With Screenflow November 18, 2011

I’ve been really enjoying screencasting my presentations, and have come up with a nice workflow using the (commercial) Mac app ScreenFlow.

Watch the video for the full details, but the basic process is:

  • Record the screen while you give the presentation in “presenter mode” (so notes are available)
  • Also record video from your computer’s camera
  • Crop down to just the slide portion of the presenter view
  • Overlay the video on the slides and make it fully transparent (Opacity 0%)
  • Skim through the video, watching for slide changes as cues
  • Insert video actions (⌘K) and flip the Opacity between (100%/0%) to show the slide or the video.

At this point, I can come up with a very nice ‘canned version’ of a presentation in only slightly more than the time it takes to simply give the presentation. It’s also a great way to rehearse!

In the video I also recommend the Samson Go Mic, ($40) which I’ve been nothing but happy with.

(The full list of Screenflow Keyboard Shortcuts is good to keep handy.)

A technical side note: the video quality in the beginng of the video is a little off. The actual “presentation” was in 4:3, but the application demo was widescreen. This meant a bit of ffmpeg magic, (attaching ’letterboxes’ to the sides to make it effectively widescreen) so I could glue the two videos together. When you actually use this method to simply give a presentation, it ends up looking even nicer.

$ ffmpeg -i -s 560x416 -r 30000/1001 -padleft 46 -padright 48 -vcodec libx264 -vpre hq -acodec libf@c -ac 2 -ar 48000 -ab 192k