PSA: Apple Silicon Users: Update ffmpeg

TLDR: If you run a Mac using Apple Silicon, update ffmpeg to dramatically speed up your encodes.

Late last year I traded in my beloved iMac Pro for an iMac Pro Portable 14" MacBook Pro. I cannot overstate how much I love this machine, and when paired with the LG UltraFine 5K, it is actually a really phenomenal setup. I have nearly all the benefits of my beloved iMac Pro, but I can pick it up and move it without a ridiculous carrying case.

When I got the machine, one of the first things I tried, for speed-testing purposes, was a ffmpeg encode. As has been mentioned before, I use ffmpeg constantly, either directly, or via Don Melton’s amazing other-transcode tool.

Given this was my first Apple Silicon Mac, and I sprung for the M1 Max, I was super excited to see how fast transcodes were going to be on this new hotness.

I was sorely disappointed. It seemed that encodes were capped at a mere 2× — about 60fps.

As it turns out, I wasn’t the only one giving this some serious 🤨. I was pointed to an issue in the repo for the aforementioned other-transcode repository. Many other people thought this looked really weird.

This was first reported in early November, and then about two months ago, the also-excellent Handbrake found a fix, which seemed to be really simple — a very special boolean needed to be set.

Thankfully, about a month ago, ffmpeg patched as well. This was eventually integrated into ffmpeg version 5.0, which was released on 14 January.

However, I install most things using Homebrew, and the Homebrew formula wasn’t updated. Using a neat trick that Homebrew supports, I was able to grab and build the latest (read: HEAD) version of ffmpeg and get fast encodes. However, if you’re not inclined to deal with stuff that fiddly, as of yesterday, the ffmpeg formula has been updated.

So, if you do any transcoding using ffmpeg on your Apple Silicon Mac, now is the time to do a brew upgrade.

Before the new ffmpeg goodies, I topped out encodes at about 2×. Now, using the latest-and-greatest released version of ffmpeg, I am getting quite a bit more than that. On a test mpeg2video file that I recorded using Channels, I was able to get a full 10×. 🎉