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I often do QuickTime screen recordings of slideshow presentations (e.g. Keynote).

These videos are 1080p 60fps and mostly text. They can go for minutes at a time with the same exact frame on-screen (static slide) yet have 60fps transitions between slides.

What are some compression tools or techniques that work best for this kind of video? I’m looking for something that keeps the text sharp while maintaining the 60fps animation transitions, without the file size being insane.

I’m not looking for answers like “use the Export for 1080p menu in QuickTime”. The best answer will have a solution that’s customized for the specific needs of a slideshow presentation video, perhaps using variable frame rate compression techniques.

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    -tune stillimage is, strictly speaking, meant for one static image for the span of the video, and will impact the slide turnover parts if those aren't simple cuts. And in my experience, I've gotten smaller files without it.
    – Gyan
    Apr 11, 2016 at 20:55

1 Answer 1

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x264 is the best-in-class encoder for generating H.264 video streams and you can use it via ffmpeg, a command-line tool, to encode to a small-sized file. Get a binary from here - opt for the latest nightly/snapshot release - and run

ffmpeg -i input.mov -c:v libx264 -crf 23 output.mov

The output will be the same constant frame rate as the input but x264 is very good at minimizing space consumed by frames which are the same as preceding ones. Lower CRF values produce better quality files at the cost of larger file sizes. 18 to 28 is a decent range to stick within.

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    This worked beautifully. I had a 17 minute 1080p screen capture of a Keynote presentation. Using this command, I was able to compress it from 278 MB to 38 MB, which is exactly what I wanted.
    – Sean Moubry
    Apr 14, 2016 at 22:53
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    I would update this answer to include x265. My experience with a 61 minute recording of a slideshow presentation was the following. Original: AVC/AAC = 1.13 GB , x264/AAC (CRF=28) = 154 MB, x265/AAC (CRF=28) = 127 MB
    – Pau Coma Ramirez
    May 26, 2020 at 11:25
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    I would consider that a marginal improvement considering heavier resource use for s/w HEVC decoding.
    – Gyan
    May 26, 2020 at 12:05
  • @Gyan Not to mention the significant increase in encoding time as well (when bulk converting videos)!
    – Mateen Ulhaq
    Sep 10, 2020 at 20:54
  • @Gyan Shaving 17.5% off of the file size of x264 is not a "marginal" improvement, and while often notoriously slow with motion content, x265 encoding time is extremely fast with videos composed almost entirely of static frames like a slideshow. I just encoded a 1280x720 5-minute greentext reading video with x265 Faster RF27.5 on a Ryzen 7 3700X in 43 seconds, for example; non-slideshow videos take 2-3 minutes on the same machine even if downscaling to 960x540.
    – Jody Bruchon
    Apr 30, 2021 at 18:37

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