OlegSmelov

FFmpeg cheat sheet

A list of useful commands for the ffmpeg command line tool.

Download FFmpeg: https://www.ffmpeg.org/download.html

Full documentation: https://www.ffmpeg.org/ffmpeg.html

Basic conversion

OlegSmelov

For what it's worth (and with all the usual disclaimers about potentially making your mac unstable by disabling system services), here's some commands that will manipulate this service and services like it. Note the $UID in the command, that's just a bash shell variable that will resolve to some number. That's your numeric UID. You just run these commands from a Terminal command line. No special privileges needed.

If you want to disable it entirely, the first command stops it from respawning, and the second kills the one that is currently running:

launchctl disable gui/$UID/com.apple.photoanalysisd
launchctl kill -TERM gui/$UID/com.apple.photoanalysisd

(If you kill it without disabling it will die, but a new one will respawn and pick up where the old one left off)

I don't have this problem myself, so I can't try these next two commands. They're relying on good ole UNIX signals. You could theoretically suspend and resume the process like this ("STOP" and "CONT" are stop and continue):

OlegSmelov

def command = [
  "sh",
  "-c",
  "shell command"
]
def proc = command.execute()
proc.waitFor()           

println "Process exit code: ${proc.exitValue()}"
println "Std Err: ${proc.err.text}"

OlegSmelov

belongs_to:

1. Assigning an object to a belongs_to association does not automatically save the object. It does not save the associated object either.

has_one:

1. When you assign an object to a has_one association, that object is automatically saved (in order to update its foreign key).
2. In addition, any object being replaced is also automatically saved, because its foreign key will change too
3. If either of these saves fails due to validation errors, then the assignment statement returns false and the assignment itself is cancelled.
4. If the parent object (the one declaring the has_one association) is unsaved (that is, new_record? returns true) then the child objects are not saved. They will automatically when the parent object is saved.