this post was submitted on 26 Oct 2024
42 points (100.0% liked)
Asklemmy
43889 readers
745 users here now
A loosely moderated place to ask open-ended questions
If your post meets the following criteria, it's welcome here!
- Open-ended question
- Not offensive: at this point, we do not have the bandwidth to moderate overtly political discussions. Assume best intent and be excellent to each other.
- Not regarding using or support for Lemmy: context, see the list of support communities and tools for finding communities below
- Not ad nauseam inducing: please make sure it is a question that would be new to most members
- An actual topic of discussion
Looking for support?
Looking for a community?
- Lemmyverse: community search
- sub.rehab: maps old subreddits to fediverse options, marks official as such
- !lemmy411@lemmy.ca: a community for finding communities
~Icon~ ~by~ ~@Double_A@discuss.tchncs.de~
founded 5 years ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
how does doing a 2pass work? I'm going to be honest, I just ignored that feature. Is it worth the extra hassle? And how much longer does it take? Also do I need to run ffmpeg twice for that? Or can I just put in an argument and it'll scan twice.
After typing all that out I realized that all this is probably easier to google/try than to ask you about it. Thanks for the info tho. I managed to get a video format where 15 minutes are 1GiB and watching it back I didn't notice any artifacts or burry parts in 1440p 60fps.
2 pass will encode a file once, and store a log of information about what it did… then on the 2nd pass it’ll use that information to better know when it should use more or less bitrate/keyframes - honestly i’m not too sure of the specifics here
now, it’s most often used to keep a file to a particular file size rather than increasing quality per se, but id say keeping a file to a particular size means you’re using the space that you have effectively
looks like with ffmpeg you do need to run it twice - there’s a log option
i mostly export from davinci resolve so i’m not too well versed in ffmpeg flags etc
doing a little more reading it seems the consensus is that spending more time on encoding (ie a higher preset) will likely give a better outcome than 2 pass unless you REALLY care about file size (like the file MUST be less than, but as close to 100mb)
I did a transcode with
-pass 1
added, and it generated an empty txt file.