FFmpeg Cheat Sheet

hello@bill.dev (Bill) — Fri, 11 Oct 2024 17:17:25 +0100

Using FFmpeg is more art than science. Every time I reach for it, I find myself trawling the internet for various incantations of the command that result in a playable video. These are commands that have worked for me.

Blu-ray

ffmpeg -i input.mkv -c:v libx265 -crf 18 -c:a aac -b:a 160k -tag:v hvc1 -ac 6 output.mp4

This results in an mp4 container with h265 video and aac sound. The file should be playable on Apple devices. The resulting file will also be significantly smaller than the original.

Docker Desktop (Mac) Unix Socket

hello@bill.dev (Bill) — Sat, 13 Apr 2024 18:37:00 +0000

Two of the tools in my container toolkit stopped working at some point recently. To demonstrate the issue, I first make sure that I have an image pulled locally.

bg@Bills-MBP ~ % docker image ls
REPOSITORY   TAG       IMAGE ID       CREATED       SIZE
golang       1.22      824aa3c1d42c   10 days ago   830MB
demo         latest    cf12555b1219   10 days ago   830MB

The first tool, Dive, started producing errors like this.

bg@Bills-MBP tmp % dive demo
Image Source: docker://demo
Fetching image... (this can take a while for large images)
Handler not available locally. Trying to pull 'demo'...
Using default tag: latest
Error response from daemon: pull access denied for demo, repository does not exist or may require 'docker login': denied: requested access to the resource is denied
cannot fetch image
exit status 1

The image was present locally and the docker daemon definitely running. I logged out, logged in again and tried different accounts. When I first hit this error I assumed that this was an issue with Dive. The workaround I used was to export the image to a .tar file and then use dive to browse the disk image. But then I hit this error with Trivy.

CommandLine on Bill Glover

FFmpeg Cheat Sheet

Blu-ray

Docker Desktop (Mac) Unix Socket