I record my college classes with QuickTime Player so I can review them later, but the files are enormous—one recording was 14 GB, and another was about 3.85 GB. The university provided the same video in a much smaller 317.7 MB file. I only need the slides and on-screen text to remain readable, so I'm fine with reducing the resolution or frame rate. What's the best way to compress these recordings without significantly hurting image quality?
2 Answers
The built-in Finder encoding option can be a convenient quick fix. Right-click the recording, choose Encode Selected Video Files, and select a smaller output size or a more compressed format. Check the result to make sure the slide text is still clear. If the quality or file-size controls aren’t sufficient, use QuickTime’s 1080p export or a dedicated encoder such as HandBrake instead.
QuickTime screen recordings are often saved with very light compression, sometimes at the monitor’s full Retina resolution. The university version was probably re-encoded with H.264 or H.265 at a much lower bitrate. Try opening the recording in QuickTime and choosing File > Export As, then select 1080p or even 720p. For lecture slides, that should usually reduce several gigabytes to a few hundred megabytes while keeping text readable. For more control, HandBrake’s Fast 1080p30 preset with an RF around 26–28 should work well. You can also reduce the frame rate to 15–20 fps since slides and lectures don’t involve much motion. In the future, recording at a scaled-down display resolution instead of native Retina resolution will produce much smaller files from the start.
I also noticed that right-clicking the video in Finder gives me an option called “Encode Selected Video Files.”
That Finder option looks useful for a quick conversion. I’ll compare its output with a 1080p export and make sure the text remains legible.